WEBVTT

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Prof: I see this is
largely,

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but of course not exclusively a
female class,

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and I know that's because of
the reputation of the class as

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being very tough on men.

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What have we learned about men
so far?

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They're violent,
they contribute only a speck of

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protoplasm to the next
generation, they help hardly at

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all in child rearing.

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In the Tuesday reading you
found that they're even afraid

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of their wives,
and on Thursday how many of you

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did the reading about the Na?

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What do they believe about
man's role in reproduction?

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Student:  Gardening.

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Prof: Just do gardening,
they just water it.

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That the baby comes totally
from the woman's substance and

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men just have to water it
occasionally.

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As you know water is water,
is water so it doesn't matter

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which man waters it,
and they have a very

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promiscuous sexuality.

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Feeling very sorry for the
males, and I don't want them to

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go through too much of an ego
crush,

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I have to tell you that some
cultures indeed give credit to

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males in all of this.

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In particular,
the Barre tribe of Venezuela,

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who are one of the isolated
tribes in the Venezuelan Amazon,

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and they believe that a woman's
body is just a vessel and that

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men do all the work of
reproduction.

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The only limitation--the very
first act of sex must be between

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husband and wife.

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They have marriages but the
first copulation has to between

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husband and wife because that
plants the seed,

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and it's very important that
the seed belong to the husband.

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Once he has planted the seed
the growing fetus is not done

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with male need,
so the fetus obviously has to

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be nourished,
it's keeping to grow has to get

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the nourishment.

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It doesn't get the nourishment
from the mother,

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it gets it from semen.

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The fetus needs a constant
contribution of semen all along

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to make it grow.

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The Barre claim that this is
very hard work for men to

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support a pregnancy.

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They have to have sex all the
time to do this and the women

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are worried about wearing out
their poor husbands.

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Now this is not just this
cultural-- just dreaming stuff

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up, this has real empirical
basis and the Barre say,

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'look it's obvious,
women grow fat during the

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pregnancy,
while men they grow thin from

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all their work,' so they have
good reasons for believing what

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they do.

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What's the solution?

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Well they ask other men to help.

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The husband--they don't want to
wear out their husband,

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he's got to do a lot of stuff.

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They ask other men to help,
and it's strange,

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even though it is such hard
work, the men seem quite willing

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to pitch in and help.

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It's very nice,
it's very heartwarming that men

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can, at least temporarily,
stop all this male/male

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competition and help another guy
when his wife needs a little

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nourishment.

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When we get to discussing the
reproductive biology that

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relates to abortion much later
in the course,

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you will find that actually
Western scientific knowledge

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does not go much beyond what the
Barre understood until about

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1840 and well into the
nineteenth century.

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That's--until then what--how a
fetus was formed,

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what the male contribution was,
what the female contribution

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was, was a big hot argument.

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Some thought it was all woman,
some thought it was all male,

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and they just had no idea.

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Human fertilization was not
discovered until 1840 in the

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West.

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We were having the same
argument that the Barre do.

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Furthermore--anybody know
approximately how long it takes

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if a human couple wants to get
pregnant how long it takes on

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average?

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It's more like five months.

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You'll hear--again when we
discuss abortion you'll hear the

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reasons for that.

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Actually, in that five months,
the husband gets the first

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copulation,
but thereafter a lot of guys

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have to help,
so by the time five months

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rolls around,
the average for getting

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impregnated,
an awful lot of guys have had

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their seed in there.

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Again, in actuality,
paternity is totally uncertain.

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That is it comes right back to
the chimp story that the

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community hangs together,
one reason because no one knows

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anything about paternity.

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Okay, last time I was
describing how all cultures have

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mechanisms so that families in
fact only have about half as

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many children of which they're
biologically capable.

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Remember we did this
calculation and we found this 69

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number and so forth.

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I was in the middle of a story
and actually it's in your

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reading.

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It's reading for last Tuesday
about the Mae Enga of New

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Guinea.

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They believe,
the males and females both

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believe, that the sexual fluids
and odors and emanations from

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women are dangerous and even
lethal to men.

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Hence, the men are terrified of
having sex with the women.

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Now you read this in your
reading and you may again throw

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it off as just one of these
cultural practices of primitive

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people,
and that's not the way you

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should approach this class.

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You should--on the other hand
ask how does such a practice

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arise?

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What are its roots?

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How does it help their culture
to survive?

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The theory being that most of
the things that people are doing

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have some role in helping them
in a difficult world.

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As you know,
in chimps as in most human

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societies,
they're exogamous,

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that instead of the male going
out to mating,

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the males stay together in one
community,

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and the females go out to
mating.

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The same is true with the Mae
Enga, and females transfer

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groups.

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Also we know that,
as in chimps,

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in New Guinea each of these
tribes is always at constant

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warfare with their neighbors.

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They are truly enemies.

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When women are exchanged
between neighboring communities

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they don't travel very far;
they'll get killed if they

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travel very far,
so the only people they know

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are the neighboring communities
and someone from this community

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will marry--
will get a woman from a fairly

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neighboring community which
means getting a wife from their

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enemy.

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That's again very similar to
the chimp setup.

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The Mae Enga are very much
aware of this,

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as you've read,
'we marry the people we fight,'

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and there's a lot of distrust
and fear of the enemy wives.

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Because of that,
the husband does not sleep in

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the hut with his wife and
children but sleeps in the men's

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hut.

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It's a male bonding sort of
thing rather than a male/female

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bonding sort of thing.

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Apparently culture has used
this distrust of the wife,

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this fear of the wife,
as a mechanism for restricting

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sexual activity.

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Of course, the Mae Enga like
every other human has

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tremendously strong sexual
drives but they're living on

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very fragile ecological land and
they can't overpopulate it,

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so they have to have some
mechanism of tamping down

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reproduction.

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This is one of the mechanisms;
the men don't even sleep in the

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same house with women.

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It's a rare event when the
women--when they visit the

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women, a rare and dangerous
event and that keeps the

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birthrate down.

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Now in the reading,
there's a third point that's

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very easy to miss because it's
just one little phrase and it

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talks about how dangerous sex
is.

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You remember who it says is
particularly vulnerable?

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The young males are partic--she
remembers that.

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The young males are
particularly vulnerable to these

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dangers and so their health will
be undermined,

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not only by frequent
intercourse with women,

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but even by frequent contact
with women.

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Of course the older men are
rather immune;

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as you grow older you gather
immunity to this.

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Now we know younger males are
driven very much sexually,

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older males it cools down
somewhat,

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and so here's this cultural
belief counteracting biology.

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It's the inverse of what you
would expect.

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You would expect the younger
men to have a lot of sex and the

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older men to sort of tail off on
it, but what does it insure?

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It insures the control by the
older, dominant,

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mature men.

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Again, it goes right back,
it's the Mae Enga;

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it can be perceived as the Mae
Enga version of dominance

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hierarchy in the chimpanzees.

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Well there's an extended
description of this in the

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reading which is wonderful,
which I hope you've already

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done.

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The--so far I've been
describing how culture,

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communities push fertility up,
because,

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if you don't get on average
eight or so children from each

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woman,
the culture disappears,

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but they also have to push it
down because if reproduction

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goes too wild the children just
die.

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I showed you data about inter
birth interval can't get too

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short or the children just die.

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Individuals--that's all from
the community perspective so

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far--but individuals,
and individual families,

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they have to adjust these
rules.

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There's these cultural rules
which are usually very strongly

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enforced,
but individual families

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have--each has a different
situation and they have to

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adjust the rules somehow to cope
with their individual situation.

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Of course this leads to
conflict between what an

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individual or an individual
family wants and what the

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culture says you must do.

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One of these examples,
I mentioned last time,

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is post-partum abstinence,
that in many parts for instance

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of Africa,
after a child is born there

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will be three years in which a
woman is not supposed to engage

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is sex.

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Obviously, primarily a
mechanism for spacing births,

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so that the children stay alive
and the woman doesn't get killed

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from too much strain on her
resources.

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Now if you think about that a
little bit,

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you have a young woman,
young husband,

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marriage is fairly young
generally,

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the husband will be a good bit
older but still young and he's

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facing--
the wife has a kid,

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he has a kid,
and the wife is face--

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the husband now facing three
years without any sex.

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What is he going to do?

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He's going to want to take a
second wife or maybe visit a lot

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of prostitutes and spend money.

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That's something that often the
wife--the first wife or second,

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or third, or wherever she is in
the chain, will not want.

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Sometimes she does want that
and we'll talk about polygamy

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later and why women very often
choose to be in polygamous

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relationships,
but very often she won't want

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him to take another wife unless
he's got a lot of money he just

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won't be able to help more than
one wife.

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What does she do?

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She has to figure out of way of
resuming sexual intercourse but

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not get pregnant.

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What does she use?

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Contraception;
so surprisingly in Africa,

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one of the major reasons for
the people accepting

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contraception is not a desire to
reduce fertility as in most all

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the rest of the world,
but a desire to resume sexual

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relationships without getting
pregnant.

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She has to do this not only to
protect herself because she

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knows that if she has children
too often she wears out her

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body,
and there's a reading on

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exactly what certain groups in
Africa--

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one group in Africa considers
this wearing out of the body.

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Also, if she gets pregnant
right away the community knows

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that she and her husband have
violated the taboo,

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and there's very strong social
proscriptions against--

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proscriptions against violating
the taboos,

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so contraception which you take
privately is sort of the perfect

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solution for women wanting to
return to sexuality but not to

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get pregnant.

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Another aspect which we
already--I just mentioned of

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control of fertility is what I
call gerontocracy,

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ruled by old folk.

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The old folk can
monopolize--the older men,

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can monopolize the sexual
activities of younger women,

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and because they're not as
vigorous shall we say that

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reduces--
is one mechanism for reducing

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fertility.

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One of the ways which came up
in one of the sections is the

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idea of bride price.

13:55.090 --> 14:00.030
Dowry is more commonly known is
where the wife's family pays the

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husband, the husband or the
husband's family when the wife

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gets married.

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The reverse of that is called
bride price and it's much more

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common then dowry in Africa.

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In this case,
the man or the man's family,

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or the man's side must pay the
father of the wife for

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the--before he gets the woman.

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It's sometimes in the West
considered buying the woman but

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it really is not a buying
situation.

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These bride prices can be very
high and a young man usually

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does not have the money to buy a
bride.

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Who controls the money of the
village?

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Who controls the resources?

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Why the older men who are the
village elders and control

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everything.

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They dole out very sparingly
the bride price to allow men to

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get married.

14:59.908 --> 15:04.708
This is like among the Maasai
of Kenya, very tall people with

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a lot of popular press about
that.

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And because the young men are
not getting married and there's

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roughly--
equal numbers of males and

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females,
that leaves a lot of excess

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young girls,
fertile young girls,

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and who gets them?

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The older men go polygamous and
they can have several wives,

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but remember for every man who
has more than one wife that

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means there's another man that
has no wife whatsoever.

15:31.269 --> 15:34.729
When you read the ethnography
of this,

15:34.730 --> 15:38.390
the anthropologists who go in,
it's very clear that the young

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men are held in a state of
sexual frustration and the young

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men have ways that they talk to
each other,

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and they are just on the verge
of rebellion.

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The strategy of the older guys
is to keep these young men just

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below that--
keep as much sex for themselves

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but keep the young men from
getting together and rebelling.

15:59.759 --> 16:03.639
They co-opt what we now
were--they co-opt the young guys

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when the older more dominant of
the younger guys,

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when things start to get out of
hand a little bit,

16:10.019 --> 16:14.089
we now have bride price,
and you can go and get married

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and that co-opts him and takes
him out of the cabal that might

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start a small revolution.

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This is all going on subtly,
often hidden within these

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communities.

16:28.179 --> 16:32.739


16:32.740 --> 16:36.130
These are large--affects this
whole polygamist situation.

16:36.129 --> 16:39.599
In much of West Africa almost
half of all wives are in

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polygamous marriages and that
means about half of the men have

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no wives whatsoever.

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And in the 1920s--so a lot of
what I'm describing is

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traditional culture and we all
know that the whole--

16:53.080 --> 16:55.110
everywhere in the world is
changing very rapidly,

16:55.110 --> 16:57.700
but you can't understand where
they're going unless you know

16:57.700 --> 16:58.930
where they're coming from.

16:58.928 --> 17:02.278
In the 1920s,
40% of the men got to be 40

17:02.277 --> 17:06.207
years old without having been
able to marry,

17:06.210 --> 17:09.440
so that's almost half your
population without

17:09.442 --> 17:13.262
"legitimate sexual
outlet" until they're 40

17:13.260 --> 17:14.290
years old.

17:14.288 --> 17:17.228
Today, even today,
and this is from a few years

17:17.231 --> 17:20.431
ago,
the median age of marriage is

17:20.430 --> 17:25.360
still almost 30 and great
pressure and power from the

17:25.363 --> 17:31.153
older guys is necessary to
maintain a situation like that.

17:31.150 --> 17:35.060
They also leave sort of a
pressure valve on this whole

17:35.057 --> 17:38.887
situation that they don't
totally suppress the sexual

17:38.892 --> 17:40.812
activity of young men.

17:40.808 --> 17:44.108
They turn a blind eye to a fair
amount of prostitution;

17:44.108 --> 17:49.008
that's reasonably accepted,
and to "discrete access to

17:49.005 --> 17:53.305
the younger wives of older
brothers or even of their

17:53.309 --> 17:54.829
fathers."

17:54.828 --> 17:57.988
Again there's the dominant
males who are sort of officially

17:57.986 --> 18:00.976
in charge, but there's a lot of
extra stuff going on.

18:00.980 --> 18:04.490
Again, it's the great ape kind
of pattern.

18:04.490 --> 18:11.430
Even today, this story of the
dominant older males getting the

18:11.431 --> 18:15.871
most sex has by no means
disappeared.

18:15.868 --> 18:24.738
Now it gets a little more
unpleasant because this control

18:24.741 --> 18:33.141
of population by pre- is very
often post-pregnancy.

18:33.140 --> 18:37.000
We've described so far all
kinds of pre-pregnancy

18:36.999 --> 18:40.889
mechanisms reducing sex,
etc., but women still get

18:40.886 --> 18:45.146
pregnant and very often they or
their families decide that they

18:45.146 --> 18:47.136
can't have these children.

18:47.140 --> 18:53.180
A lot of this is post-pregnancy
population control and even--and

18:53.182 --> 18:54.912
post-natal also.

18:54.910 --> 18:58.970
Abortion and infanticide are
common among--or have been

18:58.971 --> 19:02.131
recently--among almost all human
groups.

19:02.130 --> 19:06.250
Different communities and
different individual families

19:06.250 --> 19:10.830
have a different amount of
resources and they must match,

19:10.828 --> 19:14.098
in some way,
match their fertility to the

19:14.096 --> 19:16.626
resources that are available.

19:16.630 --> 19:21.990
This is a very discussed and
studied topic in population

19:21.988 --> 19:24.988
circles,
so a few years back Karen

19:24.990 --> 19:29.320
Mason, who was president of the
Population Association of

19:29.317 --> 19:33.877
America gave a wonderful quote
about how people adjust their

19:33.875 --> 19:35.185
family size.

19:35.190 --> 19:37.770
"Parents kill their
infants,

19:37.769 --> 19:40.639
abandon them,
neglect them in the hopes that

19:40.635 --> 19:43.745
they will die,
give them into the care of wet

19:43.749 --> 19:48.039
nurses where they usually die,
sell them, give them up for

19:48.040 --> 19:50.720
adoption,
marry them off at a young age,

19:50.721 --> 19:53.351
loan them to other families for
fostering,

19:53.348 --> 19:56.518
send them into service,
or into other households,

19:56.519 --> 19:58.959
send them to the military,
the merchant marine,

19:58.960 --> 20:02.230
prostitution,
or send them overseas as

20:02.234 --> 20:03.744
migrants."

20:03.740 --> 20:07.980
All of these are very standard
mechanisms for individual

20:07.983 --> 20:12.623
families controlling the number
of children that they have to

20:12.615 --> 20:13.305
rear.

20:13.308 --> 20:18.068
In Western culture it's
certainly not unknown,

20:18.073 --> 20:21.993
the founding myth of Jewish
people?

20:21.990 --> 20:23.820
Moses.

20:23.819 --> 20:25.279
What happened to Moses?

20:25.278 --> 20:27.298
He's a baby;
he's thrown in the basket,

20:27.301 --> 20:28.581
floated down the Nile.

20:28.578 --> 20:31.078
You go to China,
a very standard way of getting

20:31.077 --> 20:34.307
rid of children--
everywhere--every culture that

20:34.311 --> 20:36.731
has a river,
babies are put in baskets and

20:36.734 --> 20:39.434
floated down the river as a way
of getting rid of them.

20:39.430 --> 20:42.690
Of course the Bible story that
the Pharaoh's daughter finds

20:42.690 --> 20:45.890
this baby floating down the
river and you can believe that

20:45.894 --> 20:47.384
or not,
but obviously,

20:47.377 --> 20:50.437
that sort of behavior of
putting a newborn infant in a

20:50.438 --> 20:54.018
basket and floating him down the
river was apparently extremely

20:54.018 --> 20:57.878
common at that time,
so the story wouldn't have been

20:57.884 --> 20:58.804
surprising.

20:58.798 --> 20:59.748
Student:  There is one
minor difference.

20:59.750 --> 21:03.130
Moses mother didn't want to
kill him, on the contrary,

21:03.132 --> 21:04.922
she wanted him to survive.

21:04.920 --> 21:06.170
Prof: That's the story.

21:06.170 --> 21:08.040
Student:  Yeah,
because the Pharaoh would have

21:08.040 --> 21:10.310
had him killed otherwise--as all
the Jewish boys were killed.

21:10.308 --> 21:11.938
Prof: Yeah,
if you read the

21:11.941 --> 21:14.461
original--you're completely
correct, if you read the

21:14.462 --> 21:16.052
original story it reads as if 1.

21:16.045 --> 21:18.855
She wanted to keep him alive
and Pharaoh was going to kill

21:18.863 --> 21:19.653
them all, and 2.

21:19.653 --> 21:22.473
that she saw the princess sort
of on the other side of the

21:22.472 --> 21:25.442
river and thought that the
princess would see it,

21:25.440 --> 21:27.410
so you can interpret the story
as you want,

21:27.410 --> 21:30.820
but it's a very standard
multi--many, many cultures,

21:30.817 --> 21:34.227
cross-cultural mechanism of
infanticide and there it

21:34.227 --> 21:35.027
appears.

21:35.029 --> 21:38.729
What is the founding myth of
the Roman people?

21:38.730 --> 21:39.240
Students:
Romulus and Remus.

21:39.240 --> 21:42.130
Prof: Romulus and Remus;
what's the story of Romulus and

21:42.130 --> 21:42.620
Remus?

21:42.618 --> 21:45.768
Student:  Raised by a
wolf.

21:45.769 --> 21:48.769
Prof: Raised by a wolf,
so Romulus and Remus

21:48.773 --> 21:52.083
twins--we'll talk about twins in
a moment, left out on a

21:52.077 --> 21:54.667
hillside;
standard form everywhere in the

21:54.673 --> 21:57.433
world of abandonment,
you know some animal will eat

21:57.432 --> 22:00.162
it, but in this case the wolves
didn't eat the babies,

22:00.160 --> 22:03.400
they suckled them and they came
up to found the Roman Empire.

22:03.400 --> 22:10.200
Sure, so it's quite interesting
how many of the founding myths

22:10.195 --> 22:14.425
have this abandonment story in
them.

22:14.430 --> 22:16.790
With respect to twins,
for instance,

22:16.788 --> 22:19.178
the Uwa tribe who were very
traditional,

22:19.180 --> 22:21.870
isolated people in Columbia and
South America,

22:21.868 --> 22:25.648
when they have twins they
abandon them in the forest or

22:25.650 --> 22:29.350
toss them into the rivers,
and their cultural belief is

22:29.354 --> 22:30.914
that they bring bad luck.

22:30.910 --> 22:34.550
Of course in this situation
where a mother is undernourished

22:34.553 --> 22:37.953
she probably is going to have
difficulty bringing up one

22:37.950 --> 22:41.530
child,
and two is just kind of

22:41.534 --> 22:43.054
impossible.

22:43.048 --> 22:46.368
If she believes,
or the culture has sort of over

22:46.371 --> 22:50.471
history figured out that the
children are going to die,

22:50.470 --> 22:53.830
one or both of them,
then the amount of resources

22:53.833 --> 22:58.043
put into trying to raise a child
who you know is going to die

22:58.037 --> 23:00.417
anyway is just not acceptable.

23:00.420 --> 23:04.770
Of course none of this is a
conscious calculation.

23:04.769 --> 23:08.249
If you ask the people why
they're doing it,

23:08.250 --> 23:10.210
they always give some kind of
religious or mystical,

23:10.210 --> 23:13.260
or magical kind of
interpretation to this behavior,

23:13.259 --> 23:19.099
but we can see it as one of the
mechanisms for having families

23:19.102 --> 23:25.042
limit their fertility to what
they think they can cope with.

23:25.038 --> 23:28.188
In addition to controlling the
rate of reproduction,

23:28.190 --> 23:31.280
the control of population
continues after birth.

23:31.278 --> 23:35.458
We haven't talked about
abortion, but during pregnancy

23:35.462 --> 23:38.622
via abortion,
we'll get to that later.

23:38.618 --> 23:43.718
Societies are also really very
careful about controlling the

23:43.724 --> 23:46.844
number of child bearers and
they--

23:46.838 --> 23:51.318
in England, for instance,
and we'll talk a little more

23:51.316 --> 23:55.476
about this at a later time,
people couldn't marry.

23:55.480 --> 24:00.640
The peasant on somebody's
estate could not get permission

24:00.642 --> 24:06.082
to marry unless he had enough
property to support a wife and

24:06.080 --> 24:07.280
children.

24:07.278 --> 24:10.648
Very often this meant that he
couldn't marry until his father

24:10.646 --> 24:11.036
died.

24:11.038 --> 24:14.378
The father was living in the
house and he just had to wait

24:14.377 --> 24:17.887
until the father dies and then
he was owner of this property,

24:17.892 --> 24:19.652
then he could take a wife.

24:19.650 --> 24:24.380
Well the father dies when the
guy is maybe 40 or late 30s,

24:24.380 --> 24:28.110
and so that cuts down his
reproductive potential a lot,

24:28.108 --> 24:32.078
and of course the wife that he
marries has not been married up

24:32.078 --> 24:34.968
until then,
so her reproductive potential

24:34.969 --> 24:36.879
has also been knocked down.

24:36.880 --> 24:40.760
In many ways,
since the fertility of a

24:40.760 --> 24:46.420
society basically does not
depend on the number of men,

24:46.424 --> 24:51.464
it depends primarily on the
number of women.

24:51.460 --> 24:55.630
We saw this--last time we
discussed the permissibility of

24:55.625 --> 25:00.085
polygamy even with limitations
when a lot of men are dying in

25:00.089 --> 25:04.339
war,
but this happens in many,

25:04.343 --> 25:06.783
many situations.

25:06.778 --> 25:10.578
In India, as you know,
traditionally it's almost never

25:10.575 --> 25:12.075
practiced nowadays.

25:12.078 --> 25:15.778
A man dies, what happens to the
wife?

25:15.779 --> 25:17.929
Sacrificed on the funeral pyre.

25:17.930 --> 25:20.490
Again, there's all kinds of
religious and cultural

25:20.489 --> 25:23.309
explanations for it which the
people will tell you,

25:23.308 --> 25:25.768
but standing back from it among
other things,

25:25.769 --> 25:31.559
it's a way of controlling the
birthrate of the population.

25:31.558 --> 25:35.558
Sometimes in a single
geographical setting you can see

25:35.558 --> 25:38.878
the two different things working
together.

25:38.880 --> 25:41.690
The Mae Enga,
which you've already heard

25:41.690 --> 25:45.220
about in New Guinea,
they live in an overpopulated

25:45.221 --> 25:46.231
territory.

25:46.230 --> 25:50.130
They are pressing up against
the ecological limits of their

25:50.132 --> 25:50.942
resources.

25:50.940 --> 25:57.040
The women are severely degraded;
funerals are held to honor men

25:57.037 --> 26:01.127
and pigs, but not women or
children.

26:01.130 --> 26:04.210
If a husband dies,
if a man dies,

26:04.210 --> 26:09.410
his widow is strangled within
24 hours of his death.

26:09.410 --> 26:13.040
On the same island,
New Guinea, the Fore people

26:13.038 --> 26:15.168
have a different problem.

26:15.170 --> 26:18.280
They have kuru,
which we now call Creutzfeldt

26:18.278 --> 26:21.578
Jakob Disease,
a prion that destroys the brain

26:21.577 --> 26:25.437
so they have a very high death
rate and their territory is

26:25.436 --> 26:29.186
quite under populated;
they have great difficulty in

26:29.190 --> 26:31.820
getting enough people to stay
alive.

26:31.818 --> 26:35.298
In that culture,
where everybody is scarce,

26:35.301 --> 26:39.201
they mourn women and children
as much as men;

26:39.200 --> 26:43.010
they encourage premarital sex,
and widows are not killed but

26:43.009 --> 26:46.109
immediately courted for
remarriage by the men.

26:46.108 --> 26:50.298
Again, this is a society when
you're way below the limit,

26:50.300 --> 26:54.870
then you want to keep a woman's
womb full and you want to keep

26:54.867 --> 26:56.437
them reproducing.

26:56.440 --> 27:00.600
I've told you this mechanism
for reducing the number of child

27:00.595 --> 27:03.805
bearers is severe,
very severe around the world,

27:03.809 --> 27:06.419
and I mentioned and you'll hear
it again,

27:06.420 --> 27:08.680
that the estimates that there
are by various mechanisms of

27:08.680 --> 27:13.000
discrimination against women,
there's a hundred million women

27:13.000 --> 27:19.300
missing in the world and this is
a big part of the global control

27:19.297 --> 27:20.967
of population.

27:20.970 --> 27:24.980
We've seen some people and a
lot of the popular discussion

27:24.984 --> 27:28.004
thinks that fertility control,
contraception,

27:27.996 --> 27:30.976
all that is a new thing that's
burst in 1960 or something when

27:30.984 --> 27:33.824
the pill was invented--
that it just burst on the world

27:33.815 --> 27:36.675
and some people think it's
wonderful and some people think

27:36.675 --> 27:38.625
it's immoral,
but in fact,

27:38.633 --> 27:43.783
cultures have always had
mechanisms for controlling their

27:43.784 --> 27:44.984
fertility.

27:44.980 --> 27:52.650
They've often been more brutal
then what we currently have.

27:52.650 --> 27:59.110
I want to shift gears a little
bit.

27:59.108 --> 28:02.258
It follows along the following
way: so we've been talking about

28:02.262 --> 28:04.402
the way people regulate their
fertility.

28:04.400 --> 28:08.580
What is the main limitation on
fertility?

28:08.578 --> 28:11.888
Well it's often food,
and food depends on how much

28:11.888 --> 28:12.968
land you have.

28:12.970 --> 28:17.950
Most of what we read in history
and what we're used to thinking

28:17.950 --> 28:23.010
of human society has to do with
very crowded places from Europe,

28:23.011 --> 28:24.861
or China, or India.

28:24.858 --> 28:28.488
In historical times all of
these places have had very

28:28.490 --> 28:31.140
high--historically
compared--very high,

28:31.144 --> 28:33.034
even dense populations.

28:33.029 --> 28:39.619
In all of these cultures you
have masses of peasants without

28:39.618 --> 28:41.988
any land,
landless peasants,

28:41.989 --> 28:44.669
called land hunger,
everybody wants land and there

28:44.672 --> 28:47.102
isn't land for it,
they fight over land,

28:47.098 --> 28:50.388
if you manage to own land,
you're going to be very rich

28:50.392 --> 28:51.842
from land,
you don't have to work it

28:51.840 --> 28:53.380
yourself,
there's always plenty of

28:53.376 --> 28:55.736
landless peasants that can do
the work for you,

28:55.740 --> 28:58.860
and so forth.

28:58.858 --> 29:02.648
This is pretty much true
of--pretty much the characters

29:02.645 --> 29:06.195
of recent human history,
but for most of human history

29:06.196 --> 29:09.146
that was not true at all,
the opposite was true.

29:09.150 --> 29:13.560
The world was open and there
was plenty of land available.

29:13.559 --> 29:17.579
We were not a numerous species;
we had almost no population

29:17.584 --> 29:21.454
growth rate, and so what was
scarce was not land,

29:21.450 --> 29:25.400
land was plentiful,
but what was scarce was people

29:25.395 --> 29:27.405
to fill up the land.

29:27.410 --> 29:32.330
Cultures have been aware of
this problem,

29:32.328 --> 29:34.438
as well as the opposite
problem, but this problem for a

29:34.441 --> 29:36.841
long time,
so one of the great Chinese

29:36.838 --> 29:40.278
philosophers,
Mo Zi (Mo Tzu) fifth century

29:40.281 --> 29:40.711
B.C.

29:40.710 --> 29:42.790
wrote, "What is hard to
increase?"

29:42.788 --> 29:46.708
He's talking about politics and
everything, "Only people

29:46.712 --> 29:48.612
are hard to increase."

29:48.608 --> 29:52.528
He argues--he says that there
are policies which can increase

29:52.529 --> 29:53.379
population.

29:53.380 --> 29:58.110
"The kings of old required
that all men marry by the age of

29:58.106 --> 30:01.256
19 and all women marry by the
age of 14.

30:01.259 --> 30:03.879
Now those who want to marry
early marry at 20;

30:03.880 --> 30:07.530
those who want to marry late,
marry as late as 40.

30:07.528 --> 30:12.338
We can expect two or three more
children to survive if we were

30:12.344 --> 30:14.874
to reduce the age of marriage.

30:14.868 --> 30:18.148
Through universal marriage we
should be able to increase the

30:18.153 --> 30:19.493
population size."

30:19.490 --> 30:23.090
This is his advice to the
rulers on how to increase the

30:23.094 --> 30:25.234
population in their territory.

30:25.230 --> 30:27.880
There's plenty of land,
that's not a problem.

30:27.880 --> 30:29.670
They have to be strong because
there's neighboring warring

30:29.674 --> 30:31.134
states,
they're always fighting with

30:31.130 --> 30:33.690
each other,
if they don't have a big

30:33.694 --> 30:38.704
population their neighbors will
come in and wipe them out.

30:38.700 --> 30:42.740
Of course this idea that the
government should be an agent of

30:42.736 --> 30:46.366
control of the population again
has not disappeared;

30:46.369 --> 30:48.319
China does it now.

30:48.318 --> 30:50.478
In the old days they wanted to
use the government and did

30:50.476 --> 30:52.706
sometimes use the government to
increase the population.

30:52.710 --> 30:56.340
China now wants to use it to
decrease the population,

30:56.342 --> 31:00.462
but it's the same idea that
control in one way or another is

31:00.463 --> 31:02.703
important for every society.

31:02.700 --> 31:07.350
In this--the rest of this
lecture, we'll see how long it

31:07.353 --> 31:10.513
takes;
we're going to talk about under

31:10.509 --> 31:12.269
population of places.

31:12.269 --> 31:14.559
The examples are largely going
to come from the tropics,

31:14.558 --> 31:17.218
and especially we're going to
talk about Africa,

31:17.220 --> 31:21.020
and that is because until
recently the tropics have

31:21.022 --> 31:23.992
generally not had a dense
population.

31:23.990 --> 31:27.480
They have been what you might
call under-populated.

31:27.480 --> 31:29.960
People were scarce.

31:29.960 --> 31:33.610
Up to now we've been talking
about--

31:33.608 --> 31:37.438
we talked about biological
determinants of population size,

31:37.440 --> 31:39.690
of reproduction,
we've talked about cultural

31:39.685 --> 31:40.465
determinants.

31:40.470 --> 31:43.350
There's another whole big
factor: geographical

31:43.348 --> 31:44.308
determinants.

31:44.308 --> 31:48.958
And we're going to talk about
three very important

31:48.957 --> 31:53.507
geographical determinants of
population size,

31:53.509 --> 31:57.909
and largely we're using the
tropics as an example of this.

31:57.910 --> 32:01.740
The tropics generally have low
agricultural productivity.

32:01.740 --> 32:05.560
The great granaries of the
world are not in the tropics.

32:05.558 --> 32:09.398
They have parasitic diseases
which are endemic,

32:09.396 --> 32:14.146
and geographically they're
often isolated from the rest of

32:14.151 --> 32:15.821
cultural worlds.

32:15.818 --> 32:27.798
This is the--just a general map
of Africa and what you see is,

32:27.798 --> 32:31.548
this is very standard,
here is the equator and--

32:31.548 --> 32:37.638
I'm sorry here is--no this is
the equator up here,

32:37.640 --> 32:40.820
so what you have is in
Sub-Saharan Africa,

32:40.818 --> 32:44.108
well in all of Africa,
you have in the center a rain

32:44.108 --> 32:44.688
forest.

32:44.690 --> 32:50.620
This is the very traditional
jungle and it's flanked north by

32:50.624 --> 32:55.574
the Sahara Desert,
south by the Kalahari Desert.

32:55.568 --> 33:00.408
Then here is another green zone
right along the ocean and the

33:00.410 --> 33:04.210
very north,
this is Tunisia and Algeria,

33:04.207 --> 33:08.127
Morocco--
just the coastal sections of

33:08.125 --> 33:12.255
Africa are green,
they have rain.

33:12.259 --> 33:15.229
We're not going to talk about
North Africa because that's

33:15.229 --> 33:18.409
included in the Mediterranean
world, just culturally that the

33:18.411 --> 33:19.791
Sahara Desert divides.

33:19.788 --> 33:22.878
We're going to talk about
Sub-Saharan Africa.

33:22.880 --> 33:26.690
You may note that these deserts
continue into Saudi Arabia,

33:26.690 --> 33:30.340
then into the Sind Desert of
Pakistan and the Rajasthan

33:30.344 --> 33:33.484
Desert of India,
and then the Himalayas

33:33.481 --> 33:38.031
interrupt it but you get the
Gobi Desert up here and it

33:38.028 --> 33:42.578
continues across and in the
Americas there's the Amazon

33:42.575 --> 33:46.615
around the equator,
a very dense jungle,

33:46.618 --> 33:51.468
and what's the desert to the
north of the Amazon?

33:51.470 --> 33:55.020
The Sonora Desert of Mexico,
New Mexico, Arizona,

33:55.021 --> 33:59.391
that desert is in the similar
geographical position to this,

33:59.388 --> 34:01.238
it moves up and down.

34:01.240 --> 34:06.150
What's the southern desert in
South America?

34:06.150 --> 34:10.230
The Atacama Desert of Chile and
you go over the Andes and it's

34:10.226 --> 34:13.096
not quite as desert but it's the
Pampas,

34:13.099 --> 34:18.869
which is a very dry region in
Argentina,

34:18.869 --> 34:21.109
so all over the world you have
this--

34:21.110 --> 34:24.210
a central zone around the
equator which is extremely wet,

34:24.210 --> 34:28.900
flanked by desert zones,
and then once out of the desert

34:28.898 --> 34:32.478
zones you get a moderate
rainfall again.

34:32.480 --> 34:36.520
Quickly, the reason for this is
quite simple.

34:36.518 --> 34:42.418
This is the tropics,
heat comes down,

34:42.420 --> 34:44.490
the hot air rises,
it's the hottest part of the

34:44.494 --> 34:46.384
earth,
so the hot air rises,

34:46.382 --> 34:49.492
bringing up the moisture from
the tropics,

34:49.489 --> 34:54.249
as it rises it cools,
what happens as hot air-- hot

34:54.253 --> 34:55.973
moist air cools?

34:55.969 --> 34:58.719
Rain, so this is a very rainy
region.

34:58.719 --> 35:02.129
Now the air has risen,
it's dropped out its moisture,

35:02.130 --> 35:05.510
it's dry air,
the air that continues to rise

35:05.505 --> 35:09.215
pushes it away,
so it goes either north or goes

35:09.217 --> 35:11.157
south,
and it now by the time it

35:11.159 --> 35:13.859
reaches somewhat farther away
it's cooled a lot,

35:13.860 --> 35:16.910
it's dry because it lost its
rain, so now you have cool dry

35:16.911 --> 35:18.701
air,
and because this region is

35:18.695 --> 35:21.685
sucking air back in there's a
little bit of a vacuum,

35:21.690 --> 35:26.710
the air falls back down as cold
from being up here,

35:26.710 --> 35:30.310
cold dry air,
and you get the desert regions.

35:30.309 --> 35:33.859
They happen in the north and
they happen in the south so you

35:33.860 --> 35:36.570
get deserts here,
and you get deserts here.

35:36.570 --> 35:39.040
This is just a characteristic
of the whole world,

35:39.036 --> 35:41.396
and of course this is
interrupted by oceans;

35:41.400 --> 35:43.740
this is interrupted by
something like the Himalaya

35:43.742 --> 35:47.632
Mountains so there's a lot of--
it's not a perfect schema but

35:47.628 --> 35:52.088
it explains an awful lot of the
geography of the earth.

35:52.090 --> 35:54.880
In this schema,
as I've just showed you,

35:54.880 --> 35:59.320
in Africa, look how much of it
is taken up with that schema.

35:59.320 --> 36:01.680
It's from here,
from the north edge of the

36:01.675 --> 36:04.945
Sahara Desert to the south edge
of the Kalahari Desert.

36:04.949 --> 36:08.979
It turns out its 97% of Africa
or something;

36:08.980 --> 36:13.880
93% of Africa lies in one of
those regions;

36:13.880 --> 36:18.570
a very wet jungle or too dry
and you just have a very thin

36:18.565 --> 36:20.915
region here,
and some region here,

36:20.916 --> 36:23.676
which gets some of the monsoon
circulation of air,

36:23.679 --> 36:28.349
of warm air out of the ocean.

36:28.349 --> 36:34.089
We have the image of the wet
tropics anyway as extremely lush

36:34.090 --> 36:40.120
and fertile and you think what a
wonderful place for farming.

36:40.119 --> 36:42.329
It's a tropical paradise.

36:42.329 --> 36:44.899
Actually nothing is farther
from the truth;

36:44.900 --> 36:49.220
the tropics are generally very
difficult to farm and if you do

36:49.222 --> 36:52.912
farm them, they're very poorly
productive regions.

36:52.909 --> 36:55.279
Why is this?

36:55.280 --> 36:58.540
How many of you are aware of
that, that the tropics are not

36:58.541 --> 36:59.611
good for farming?

36:59.610 --> 37:02.930
All you Forestry guys ought to
be aware of this.

37:02.929 --> 37:12.879
The reason is that the soils
are very bad and they're bad for

37:12.880 --> 37:16.530
a number of reasons.

37:16.530 --> 37:18.780
Well let's go back a little bit.

37:18.780 --> 37:23.520
Plant growth is very rarely
limited by sunlight.

37:23.518 --> 37:27.228
What the tropics have is plenty
of sunlight but it's very rare

37:27.230 --> 37:30.090
that that is the limitation on
plant growth,

37:30.090 --> 37:34.300
so the most productive part of
the world is in terms of

37:34.298 --> 37:35.778
bio-productivity?

37:35.780 --> 37:38.200
The ocean around
Antarctica--very,

37:38.197 --> 37:41.787
very cold region in terms of
intensity of sun,

37:41.789 --> 37:44.449
every part of the world gets
the same number of hours of

37:44.454 --> 37:47.034
sunlight in a year,
but the intensity around

37:47.029 --> 37:50.089
Antarctica is very much less,
so there's very little

37:50.090 --> 37:52.820
sunlight, yet you get these
tremendous algal blooms,

37:52.820 --> 37:54.670
the krill eat them,
the whales eat the krill,

37:54.670 --> 37:57.590
and it's a tremendous
productive region.

37:57.590 --> 37:57.800
Why?

37:57.797 --> 37:59.677
It has nothing to do with
sunlight;

37:59.679 --> 38:01.499
it has nothing to do with
temperature.

38:01.500 --> 38:04.070
You have Antarctica,
the continent of Antarctica,

38:04.070 --> 38:07.660
which has rock down below it,
it's not like the North Pole,

38:07.659 --> 38:12.179
there's rock there and the
glaciers slide down to the sea

38:12.179 --> 38:14.279
and they grind the rock.

38:14.280 --> 38:17.630
Where the glacier is
coming--falling into the sea,

38:17.630 --> 38:22.120
underneath is a layer of what
they call glacier flour and

38:22.123 --> 38:24.853
that's ground rock,
falls into the sea,

38:24.849 --> 38:27.069
fertilizes the sea,
tremendously

38:27.065 --> 38:33.135
valuable--tremendously nutrient
rich and then that circulates up

38:33.139 --> 38:37.079
the west coast of Chile,
for instance the pacific coast

38:37.076 --> 38:38.666
of Chile,
the Humboldt current you may

38:38.668 --> 38:41.088
have heard of,
brings up all these nutrients

38:41.085 --> 38:44.975
and the richest fishing banks in
the world are off Peru where the

38:44.983 --> 38:48.513
Humboldt current comes up and
brings all these nutrients to

38:48.514 --> 38:49.554
the surface.

38:49.550 --> 38:53.630
All over the world nutrients
are almost always what limit

38:53.630 --> 38:54.650
agriculture.

38:54.650 --> 38:56.910
Well what's the story in the
tropics?

38:56.909 --> 39:02.589
The soil may have started with
a lot of nutrients at some time

39:02.594 --> 39:04.864
back,
but the rains come,

39:04.855 --> 39:08.515
a huge amount of rain,
and what does rain do,

39:08.521 --> 39:11.071
washes the nutrients back away.

39:11.070 --> 39:16.800
In most places nutrients are
recovered by several mechanisms.

39:16.800 --> 39:22.430
One is by mountains being
eroded down, that the mountains

39:22.434 --> 39:23.244
erode.

39:23.239 --> 39:25.659
In February,
I was in the Peruvian Amazon

39:25.659 --> 39:29.289
and you're sitting there right
in the shadow of the Andes and

39:29.291 --> 39:33.031
the rains come into the Andes,
erode the rock,

39:33.027 --> 39:39.167
and parts of the Amazon have
rich water flowing through it

39:39.170 --> 39:42.190
with the Andes nutrients.

39:42.190 --> 39:46.880
Most of the Amazon is flat,
does not have any runoff from

39:46.880 --> 39:50.060
the Andes Mountains,
infertile as hell,

39:50.063 --> 39:51.993
no nutrients there.

39:51.989 --> 39:55.719
How does the jungle--so you
have this nutrient poor soil,

39:55.715 --> 39:59.435
if you go there you'll see the
soil is extremely thin.

39:59.440 --> 40:03.280
You take your boot and you kick
it and a few--

40:03.280 --> 40:07.510
an inch or two and there's no
soil left and if you look at the

40:07.505 --> 40:09.935
trees,
what do the roots of tropical

40:09.936 --> 40:11.366
trees often look like?

40:11.369 --> 40:14.339
These huge things because
there's not enough soil to

40:14.340 --> 40:17.560
support them on deep roots,
there's nothing down there,

40:17.559 --> 40:20.389
so they spread out and
hopefully stay upright because

40:20.391 --> 40:23.831
with these huge,
huge buttressed kind of roots.

40:23.829 --> 40:27.219
Everything is telling you,
if you know how to look at

40:27.215 --> 40:31.315
everything, it's telling you
that this is thin and poor soil.

40:31.320 --> 40:34.680
Nevertheless,
there's all this biomass in the

40:34.682 --> 40:39.582
jungle and the mechanism is that
the whole floor of the jungle is

40:39.576 --> 40:42.986
covered with a fungus,
with a fungal mat,

40:42.990 --> 40:47.630
when a leaf falls and it's wet,
and so then it's never--cannot

40:47.625 --> 40:51.285
fall far from a fungus because
they're everywhere.

40:51.289 --> 40:55.149
The fungal hyphae,
the sort of root of the fungus

40:55.154 --> 40:59.824
in a sense, invades the leaf and
very rapidly sucks out its

40:59.822 --> 41:00.952
nutrients.

41:00.949 --> 41:02.569
What does it do with those
nutrients?

41:02.570 --> 41:07.180
Well one end of the fungus is
attached to the decaying leaves

41:07.184 --> 41:09.804
and other stuff that falls down.

41:09.800 --> 41:12.910
The other end is attached to
the trees, and it gives these

41:12.907 --> 41:14.267
nutrients to the trees.

41:14.269 --> 41:16.569
Why is it so generous?

41:16.570 --> 41:20.400
Well the trees must be giving
something to the fungus.

41:20.400 --> 41:22.090
Well the trees are up there in
sunlight.

41:22.090 --> 41:24.130
The jungle floor is dark.

41:24.130 --> 41:27.260
The canopy of the forest let's
very little sunlight in,

41:27.262 --> 41:30.222
so they can't photosynthesize
down at the bottom.

41:30.219 --> 41:34.699
It's--there's not a lot of
grass and stuff under jungle

41:34.695 --> 41:35.355
trees.

41:35.360 --> 41:38.970
The trees make the sugars
through photosynthesis,

41:38.969 --> 41:42.179
they send them down,
pass them to the fungus,

41:42.179 --> 41:43.859
the fungus decays and
everything else sends the

41:43.864 --> 41:45.114
nutrients back up into the tree.

41:45.110 --> 41:49.410
It's a wonderful cycle and so
basically all the nutrients are

41:49.409 --> 41:52.349
up in the jungle canopy,
up in the forest,

41:52.346 --> 41:53.776
not in the soil.

41:53.780 --> 41:59.800
This stuff, this decaying
vegetable matter is the source

41:59.800 --> 42:05.930
of fertility and you measure how
much of it there is,

42:05.929 --> 42:10.089
and the productivity of the
soil depends very closely to the

42:10.090 --> 42:14.330
percent and depth of the humus,
this stuff is called humus in

42:14.333 --> 42:14.973
the soil.

42:14.969 --> 42:20.079
In tropical soils it's less
than 2% of the soil that things

42:20.083 --> 42:21.763
live in is humus.

42:21.760 --> 42:24.260
In temperate soils it's always
over 10%;

42:24.260 --> 42:28.070
in upper New York state or Ohio
it's 10% to 12%,

42:28.074 --> 42:31.974
and the richest Iowa farmlands
it's up to 16%.

42:31.969 --> 42:35.099
So you can see the productivity
of Iowa is just going to be--

42:35.099 --> 42:37.639
just from the soil
consideration--there's going to

42:37.641 --> 42:40.861
be an awful lot greater than the
productivity of the Amazon.

42:40.860 --> 42:46.930
Another thing is the rapidity
of decay aside--

42:46.929 --> 42:49.089
anything that the fungus
doesn't get,

42:49.090 --> 42:53.270
which is rare,
decays by bacteria and maybe

42:53.273 --> 42:57.263
other fungi that don't feed the
trees.

42:57.260 --> 43:00.830
It's hot, it's hot all the time
in the Amazon,

43:00.827 --> 43:05.027
and what does temperature do to
chemical reactions?

43:05.030 --> 43:07.790
Speeds them up,
so for every ten degrees warmer

43:07.793 --> 43:11.043
the chemical reaction in general
goes twice as fast.

43:11.039 --> 43:14.819
In a jungle floor--in a jungle
you'll have maybe 30 degrees

43:14.815 --> 43:19.365
higher than New York state,
than Ohio, or Iowa so that's

43:19.367 --> 43:22.297
two, four,
eight--decay will go eight

43:22.300 --> 43:25.940
times as fast as in say New York
or in my backyard;

43:25.940 --> 43:29.060
to say nothing of the absence
of the winter where decay

43:29.063 --> 43:31.033
basically doesn't happen at all.

43:31.030 --> 43:34.800
I know I make a mulch pile and
it takes four years.

43:34.800 --> 43:37.950
When I put in a leaf,
four years later it's down to

43:37.949 --> 43:40.089
good soil,
and then takes more years,

43:40.086 --> 43:42.966
I don't know how many before
that turns all back to carbon

43:42.974 --> 43:44.044
dioxide and water.

43:44.039 --> 43:47.229
The whole thing is organic;
the whole thing eventually goes

43:47.230 --> 43:47.610
away.

43:47.610 --> 43:53.260
In a jungle it happens much,
much more quickly.

43:53.260 --> 43:56.190
To summarize all this,
this is--you've got to have

43:56.193 --> 43:57.993
some biology in this course.

43:57.989 --> 44:04.989
What is--which is more fertile,
the Sahara Desert or the Amazon

44:04.987 --> 44:05.887
Basin?

44:05.889 --> 44:08.319
The answer is really surprising.

44:08.320 --> 44:11.730
There's a quote,
"Annually millions of tons

44:11.726 --> 44:15.706
of dust from the Sahara are
blown by the northeast trade

44:15.711 --> 44:18.541
winds,
thousands of kilometers across

44:18.543 --> 44:19.903
the Atlantic Ocean.

44:19.900 --> 44:23.090
There they settle upon the
Amazon.

44:23.090 --> 44:26.210
Some scientists suggest that
this is one of the major sources

44:26.206 --> 44:29.216
of soil nutrients for the poor
soil of the Amazon."

44:29.219 --> 44:33.999
It's really--and not a mild
situation;

44:34.000 --> 44:36.760
it's very extreme,
if nutrients from the Sahara

44:36.755 --> 44:39.985
can blow a few thousand miles
and drop in and be a very

44:39.992 --> 44:43.052
significant source of nutrients
for the Amazon.

44:43.050 --> 44:49.080


44:49.079 --> 44:52.239
Now, what happens if you try to
farm this place?

44:52.239 --> 44:54.589
Try to farm in a jungle,
what do you do?

44:54.590 --> 44:56.120
Well you have to chop down the
trees, right?

44:56.119 --> 44:58.019
Now mind you,
I told you that the forest

44:58.018 --> 45:00.498
floor is moist and dark,
and if any of you have been

45:00.500 --> 45:02.740
there, you'd know that it's very
striking.

45:02.739 --> 45:05.069
You're not boiling at all.

45:05.070 --> 45:08.550
Now you cut down the trees;
the sun now beats down,

45:08.548 --> 45:11.878
the tropical sun can be quite
brutal and it dries out the

45:11.882 --> 45:13.492
soil, it bakes the soil.

45:13.489 --> 45:15.539
What dies?

45:15.539 --> 45:19.929
The fungi die because fungi
need coolish and moist

45:19.934 --> 45:21.194
environment.

45:21.190 --> 45:25.190
They die, your means of
recycling nutrients is gone;

45:25.190 --> 45:27.650
the soil has very little
nutrients itself.

45:27.650 --> 45:31.950
What have you done with the
trees that you chopped down?

45:31.949 --> 45:35.089
If you're a commercial
agriculture place you ship them

45:35.094 --> 45:38.064
down river to a saw mill,
so the nutrients that are

45:38.059 --> 45:39.839
there, they're taken away.

45:39.840 --> 45:42.210
The secret of what's called
Swidden agricultural,

45:42.210 --> 45:46.160
slash and burn agriculture,
is that yes they do chop down

45:46.161 --> 45:49.881
the trees but in a very local,
very small plot of land,

45:49.875 --> 45:53.105
and they burn the trees in
place and that puts the ash as

45:53.108 --> 45:56.628
the mineral nutrients which are
so missing and that fertilizes

45:56.630 --> 45:57.440
the soil.

45:57.440 --> 46:00.510
It's not wonderfully efficient
but it does work if you keep

46:00.505 --> 46:02.775
your plot small because then the
fungus,

46:02.780 --> 46:06.730
which is killed there,
can reinvade from the

46:06.731 --> 46:08.571
surrounding trees.

46:08.570 --> 46:12.380
You start doing commercial
farming with many,

46:12.382 --> 46:16.892
many acres of spread then
there's no way that soil is

46:16.889 --> 46:18.969
going to regenerate.

46:18.969 --> 46:22.049
How does this work out?

46:22.050 --> 46:26.200
For instance,
in the Yucatan of Mexico,

46:26.197 --> 46:30.997
the Maya lived there for a very
long time.

46:31.000 --> 46:34.970
In the sixteenth century,
a Franciscan bishop Diego de

46:34.974 --> 46:37.704
Landa,
who was--he wrote everything,

46:37.704 --> 46:41.674
everything we know about the
pre-colonial Mayan existence

46:41.673 --> 46:42.953
comes from him.

46:42.949 --> 46:45.189
The Yucatan,
this is from him,

46:45.193 --> 46:49.223
"The Yucatan is the
country with the least earth

46:49.217 --> 46:51.737
that I have seen,
since all of it is one living

46:51.740 --> 46:52.810
rock,
and has wonderfully little

46:52.806 --> 46:53.236
earth."

46:53.239 --> 46:57.789
When you read all these
chronicles they always are--

46:57.789 --> 47:00.999
they're speaking always of
famines in the Yucatan because

47:00.996 --> 47:04.136
there's so little productivity
and how do they avoid the

47:04.144 --> 47:06.354
famines,
and this is again before the

47:06.347 --> 47:07.177
Spaniards came.

47:07.179 --> 47:12.079
They take care of their--they
have exports which they exchange

47:12.079 --> 47:14.569
for food from better regions.

47:14.570 --> 47:16.530
What do they export?

47:16.530 --> 47:21.250
Honey; which you don't have to
farm, salt which you don't farm,

47:21.250 --> 47:22.240
and slaves.

47:22.239 --> 47:25.199
That's another use for
"excess people"

47:25.197 --> 47:28.217
and controlling your
population, you sell them as

47:28.217 --> 47:28.907
slaves.

47:28.909 --> 47:32.629
You look all over the
pre-modern world and of course

47:32.626 --> 47:35.976
you know it's not gone in the
modern world,

47:35.980 --> 47:40.760
slavery is a very big thing and
a very big part of what happens

47:40.757 --> 47:41.987
to population.

47:41.989 --> 47:43.639
We'll talk a little bit about
that later.

47:43.639 --> 47:49.159
Well let me say it now as long
as the topic came up.

47:49.159 --> 47:51.499
What is slavery a response too?

47:51.500 --> 47:54.640
It's very relevant to this
lecture--under population.

47:54.639 --> 47:58.279
You don't have enough laborers
so you import slaves.

47:58.280 --> 48:00.770
In the middle of Europe,
where you have teeming

48:00.768 --> 48:03.638
populations, or India,
or China, are you going to have

48:03.635 --> 48:05.145
an awful lot of slavery?

48:05.150 --> 48:11.460
No, there's no land for them to
be utilized.

48:11.460 --> 48:13.680
Slaves get used,
like in the Roman Empire,

48:13.679 --> 48:16.149
not as farmers;
there were hordes of Romans,

48:16.150 --> 48:19.030
peasants that would love to
have some land to farm.

48:19.030 --> 48:22.770
They're used in the mines;
there were household slaves,

48:22.769 --> 48:24.729
sex slaves, in the mines.

48:24.730 --> 48:29.350
The Arab countries took a lot
of slaves through Madagascar and

48:29.349 --> 48:31.969
continental Africa;
household slaves,

48:31.967 --> 48:35.467
sex slaves, somewhat in the
mines but they didn't have that

48:35.472 --> 48:36.322
many mines.

48:36.320 --> 48:39.860
Slavery is a response to under
population.

48:39.860 --> 48:42.240
Where do you get huge slavery?

48:42.239 --> 48:46.439
When you discover the new world
and how you have this very thin

48:46.442 --> 48:48.952
Indian population in these
worlds,

48:48.949 --> 48:52.779
largely because we killed them
with diseases as you either have

48:52.782 --> 48:54.022
read or will read.

48:54.018 --> 48:57.948
You have an under
populated--two under populated

48:57.949 --> 49:01.209
huge continents with much good
land,

49:01.210 --> 49:04.520
you first in Western--in
history first you try to enslave

49:04.521 --> 49:07.141
the Indians,
the Indians don't do very well,

49:07.141 --> 49:09.621
they die out,
so you stop that and you import

49:09.615 --> 49:11.775
African slaves who manage to
stay alive.

49:11.780 --> 49:15.630
Slavery itself is a response to
under population.

49:15.630 --> 49:18.390
It fits exactly into what I am
talking about.

49:18.389 --> 49:20.819
Wherever you see massive
slavery you're going to find

49:20.822 --> 49:24.002
under-population,
you're going to find areas of

49:23.998 --> 49:27.428
land that have nobody on them,
and someone can,

49:27.429 --> 49:33.909
by military force,
capture people and force them

49:33.909 --> 49:38.279
to work for themselves.

49:38.280 --> 49:43.580
There's many other reasons why
the tropics are hard to farm.

49:43.579 --> 49:48.569
Where are the grain belts in
the world?

49:48.570 --> 49:50.660
What do you know about--where
is grain grown?

49:50.659 --> 49:58.749
Where is the really rich places?

49:58.750 --> 50:00.990
Anybody?

50:00.989 --> 50:01.729
Student:  US.

50:01.730 --> 50:03.450
Prof: U.S.,
where in the U.S.?

50:03.449 --> 50:04.149
Student: Midwest.

50:04.150 --> 50:06.190
Prof: Midwest,
upper Midwest,

50:06.192 --> 50:07.712
Iowa, Kansas,
Minnesota.

50:07.710 --> 50:09.900
Does it go north of the U.S.?

50:09.900 --> 50:10.480
Student:  Yes.

50:10.480 --> 50:12.310
Prof: Yes,
Saskatchewan,

50:12.309 --> 50:15.549
Alberta, way the heck up there,
you have this fabulous

50:15.545 --> 50:17.005
production of grain.

50:17.010 --> 50:21.250
You see pictures of northern
Saskatchewan in Canada with the

50:21.251 --> 50:22.691
big grain reapers.

50:22.690 --> 50:26.710
China, where are the great
grain fields of China?

50:26.710 --> 50:35.720
Wheat--up in Manchuria,
goes up the northeast of China,

50:35.719 --> 50:37.909
is all grain,
all wheat, way up into

50:37.907 --> 50:40.817
Manchuria,
and Manchuria goes up it's more

50:40.824 --> 50:43.954
or less the same as Alberta and
Saskatchewan.

50:43.949 --> 50:48.199
In the south you don't get your
great grain growing regions in

50:48.204 --> 50:51.484
the tropical region,
certainly not in the desert

50:51.483 --> 50:52.323
regions.

50:52.320 --> 50:54.270
You get them--Morocco,
for instance,

50:54.273 --> 50:57.733
has very productive agriculture
right on the coast where it's a

50:57.731 --> 50:58.571
wet region.

50:58.570 --> 51:01.130
That's not very far north,
and down in South Africa,

51:01.125 --> 51:03.325
and Africa just doesn't go that
far south.

51:03.329 --> 51:06.579
In South America you get it
down in Argentina,

51:06.579 --> 51:10.039
so again--so there's something
that agriculture gets more

51:10.039 --> 51:12.449
productive the further north you
go,

51:12.449 --> 51:15.109
with a limit of course,
it doesn't go into the tropics.

51:15.110 --> 51:15.980
Why should that be?

51:15.980 --> 51:19.160
That goes contrary to our
expectation.

51:19.159 --> 51:23.179
Again, the reason is
biologically rather simple.

51:23.179 --> 51:26.469
During the daytime,
plants take in the sunlight and

51:26.469 --> 51:28.179
make sugar, make energy.

51:28.179 --> 51:32.579
They also respire,
they also have to run their own

51:32.581 --> 51:35.231
machinery,
so they're also using energy,

51:35.231 --> 51:39.831
using sugar all the time,
they use it day and they use it

51:39.831 --> 51:40.561
night.

51:40.559 --> 51:44.719
Now the sun goes down and
photosynthesis shuts down,

51:44.719 --> 51:47.379
but respiration continues,
they have to keep themselves

51:47.382 --> 51:50.942
alive at night just as we do,
we don't stop breathing when we

51:50.938 --> 51:51.768
go to sleep.

51:51.768 --> 51:55.388
The ratio between daylight and
nighttime, how many hours of

51:55.385 --> 51:58.685
daylight and how many of
nighttime is a very important

51:58.692 --> 52:00.752
factor in plant productivity.

52:00.750 --> 52:05.770
In the tropics what's the ratio
of daylight to nighttime the

52:05.771 --> 52:07.391
whole year round?

52:07.389 --> 52:09.259
Student:  1:1
Prof: About 12/12,

52:09.264 --> 52:09.844
about equal.

52:09.840 --> 52:12.930
What is it up in Saskatchewan
or Manchuria?

52:12.929 --> 52:15.589
Daylight, daylight,
daylight, very little

52:15.590 --> 52:16.390
nighttime.

52:16.389 --> 52:19.409
The plants have so many more
hours in which they're

52:19.411 --> 52:22.681
photosynthesizing and much
smaller amount of time where

52:22.675 --> 52:25.935
they're not photosynthesizing
but still respiring.

52:25.940 --> 52:29.360
That's one big factor why you
get these grain belts going up

52:29.364 --> 52:29.834
north.

52:29.829 --> 52:33.579
Also temperature,
how much energy does it take

52:33.583 --> 52:36.423
you to just keep yourself alive?

52:36.420 --> 52:38.710
Well we've just said,
all chemical reactions go--

52:38.710 --> 52:41.320
every ten degrees they more or
less double,

52:41.320 --> 52:44.490
so respiration plants the
warmer they are,

52:44.489 --> 52:45.719
the more respiration they have.

52:45.719 --> 52:50.659
At nighttime it's still warm,
so everything is working rather

52:50.659 --> 52:52.469
fast in the tropics.

52:52.469 --> 52:55.359
In Canada, it's a lot of sun
during the day,

52:55.355 --> 52:59.175
but it cools off at night,
and so respiration is at a very

52:59.179 --> 53:00.119
low level.

53:00.119 --> 53:03.799
The productivity of a plant is
the balance between its

53:03.804 --> 53:06.674
photosynthetic productions,
it's production,

53:06.672 --> 53:10.312
and its respiration,
use of that produce for its own

53:10.313 --> 53:11.143
purposes.

53:11.139 --> 53:15.659
There's a big difference in the
ratio in the north from Iowa to

53:15.661 --> 53:20.131
Saskatchewan,
or from the Yangtze up into

53:20.125 --> 53:25.675
Manchuria,
that ratio is just much better

53:25.684 --> 53:29.374
than it is in the tropics.

53:29.369 --> 53:34.759
We won't continue too much with
this.

53:34.760 --> 53:37.160
We can also talk about the
diseases that--

53:37.159 --> 53:41.649
in tropical regions you get
Malaria,

53:41.650 --> 53:45.810
you get a whole bunch of insect
borne diseases,

53:45.809 --> 53:50.839
tsetse flies carry sleeping
sickness, etc.

53:50.840 --> 53:54.920
One to two million Africans die
of Malaria every year and that's

53:54.918 --> 53:56.988
about the same number as AIDS.

53:56.989 --> 54:01.029
Malaria and Aids are about
equally devastating to a

54:01.028 --> 54:02.078
population.

54:02.079 --> 54:07.029
It's about 11% to 22% of all
deaths in Africa are Malaria

54:07.025 --> 54:07.815
deaths.

54:07.820 --> 54:09.950
Yellow fever,
Leishmaniasis,

54:09.954 --> 54:13.594
bilharzia , roundworm,
hook worm, the number of

54:13.590 --> 54:18.260
parasites that live in tropical
regions is enormous and very

54:18.255 --> 54:21.335
often they kill humans and
make--

54:21.340 --> 54:25.440
they can't go in there to farm
because they'll die.

54:25.440 --> 54:29.950
Why are the tropics so much
more susceptible to disease,

54:29.951 --> 54:33.811
this kind of disease,
insect born stuff than the

54:33.806 --> 54:35.526
northern regions?

54:35.530 --> 54:40.860
It's a simple factor, winter.

54:40.860 --> 54:43.750
Winter kills insects,
it kills them massively,

54:43.746 --> 54:47.786
very hard for insects to not
freeze to death over the winter.

54:47.789 --> 54:51.349
Tropics don't have winter so
it's a whole class of problems;

54:51.349 --> 54:54.119
they dry out,
the winter is extremely dry,

54:54.123 --> 54:57.983
they go desiccate and freeze
and it's very--organisms kill

54:57.981 --> 54:58.591
them.

54:58.590 --> 55:01.240
In the tropics,
nice all the time,

55:01.244 --> 55:05.194
insects just have a good time
and they can evolve,

55:05.188 --> 55:10.418
use their evolution to attack
animals and people much better.

55:10.420 --> 55:17.900
All of this really adds up and
geography counts and people have

55:17.900 --> 55:21.280
to adapt to the geography.

55:21.280 --> 55:24.490
In this case the adaptation is
to an under-population and I'm

55:24.494 --> 55:25.624
going to show you--

55:25.619 --> 55:38.359


55:38.360 --> 55:43.210
well just to give you an idea
of how densely populated Africa

55:43.208 --> 55:46.018
is or isn't,
here are some European--some

55:46.018 --> 55:47.158
non-African places.

55:47.159 --> 55:49.929
Netherlands is one of the most
crowded in the world;

55:49.929 --> 55:54.009
1,011 people per square mile.

55:54.010 --> 55:58.370
Japan: 870, but that's--in
terms of arable land Japan is

55:58.371 --> 55:59.881
mostly mountains.

55:59.880 --> 56:02.250
They just have very small areas
where people can land,

56:02.251 --> 56:04.131
so to compare the Netherlands
are all flat,

56:04.132 --> 56:05.522
people can live everywhere.

56:05.518 --> 56:08.208
But if you want to compare this
to that they're probably--per

56:08.211 --> 56:10.861
arable land where it's more
crowded than the Netherlands.

56:10.860 --> 56:14.950
Belgium same as here,
India, China and again China is

56:14.945 --> 56:17.665
the same thing,
they have the whole Himalaya

56:17.668 --> 56:20.788
Mountains in the west,
the whole huge dry regions in

56:20.791 --> 56:24.001
the north,
Tibet--Mongolia and the

56:24.003 --> 56:30.333
northwest regions so this is way
an underestimate for China.

56:30.329 --> 56:34.269
Mexico has a lot of desert,
looks fairly under populated,

56:34.269 --> 56:37.929
but a lot of that is because
you got desert space.

56:37.929 --> 56:42.369
Now you go to Africa,
Nigeria one of the most densely

56:42.367 --> 56:45.437
places is 346,
that's not extreme.

56:45.440 --> 56:51.210
Since Nigeria it's all--no
mountains, no deserts.

56:51.210 --> 56:54.060
In principle all of this land
could be used so that's a real

56:54.056 --> 56:56.056
number,
whereas, the Chinese number you

56:56.063 --> 56:58.133
should multiply it by a factor
of three,

56:58.130 --> 57:00.520
it's about a third of the
Chinese land that's actually

57:00.518 --> 57:03.218
arable,
so China is ballpark 1,000 and

57:03.215 --> 57:05.755
Nigeria is about a third of
that.

57:05.760 --> 57:09.300
Kenya is down--again Kenya is
pretty much all livable,

57:09.302 --> 57:11.512
and they have a low population.

57:11.510 --> 57:14.270
Madagascar's all livable.

57:14.269 --> 57:15.839
Angola is all livable.

57:15.840 --> 57:18.950
Mali and Niger have deserts so
those numbers have to be

57:18.949 --> 57:19.639
corrected.

57:19.639 --> 57:21.779
Congo doesn't have deserts.

57:21.780 --> 57:25.630
The point is that the
population density in Africa is

57:25.628 --> 57:29.328
a lot less than other places
that we think are--

57:29.329 --> 57:33.589
we don't think of Holland as
overpopulated,

57:33.590 --> 57:38.500
but in terms of just a simple
people per arable land it

57:38.503 --> 57:39.963
definitely is.

57:39.960 --> 57:42.960
Africans, again,
we're looking at something that

57:42.956 --> 57:45.056
has a big historical component.

57:45.059 --> 57:47.629
I have to be careful when I'm
talking--what era of time I'm

57:47.630 --> 57:48.340
talking about.

57:48.340 --> 57:51.700
These are modern numbers I'm
going to show you but they

57:51.695 --> 57:54.925
reflect people's attitudes that
have changed that are

57:54.927 --> 57:57.597
appropriate for some time in the
past,

57:57.599 --> 57:59.019
and only change very slowly.

57:59.018 --> 58:01.938
This is Morocco on the coast,
this is not part of the

58:01.940 --> 58:03.400
Sub-Saharan Africa zone.

58:03.400 --> 58:07.030
This is very integrated into
the Mediterranean zone.

58:07.030 --> 58:09.050
Almost everything you can say
about its culture,

58:09.052 --> 58:10.692
it's really a Mediterranean
culture.

58:10.690 --> 58:13.770
Look what's happened to its
fertility over time.

58:13.768 --> 58:15.158
It was very high,
more or less equal to every

58:15.164 --> 58:18.704
other place,
7.2 children per women and that

58:18.702 --> 58:22.812
stayed the same,
but in recent times it's gone

58:22.813 --> 58:25.793
down to less than half of that,
3.2.

58:25.789 --> 58:27.849
This is not the most recent
data.

58:27.849 --> 58:30.229
I wanted to show you a little
bit older data.

58:30.230 --> 58:32.280
It's gone down even further.

58:32.280 --> 58:36.950
That zone of North Africa,
Tunisia is at replacement

58:36.949 --> 58:40.249
fertility level,
and North Africa has

58:40.246 --> 58:42.716
characteristic of this.

58:42.719 --> 58:46.929
Now I'm going to show you the
next country to the south which

58:46.927 --> 58:47.627
is Mali.

58:47.630 --> 58:50.970
I'm sorry Niger,
because Mali is also there,

58:50.974 --> 58:55.804
but Niger is--when you go south
you cross the Sahara Desert and

58:55.798 --> 58:58.598
you're in Sub-Sahara and Africa.

58:58.599 --> 59:02.009
Now look at its fertility,
this is even a little bit later

59:02.014 --> 59:04.354
in time, and look at its
fertility rate,

59:04.351 --> 59:06.031
it hasn't budged at all.

59:06.030 --> 59:08.980
It's again, eight--seven,
eight children,

59:08.983 --> 59:12.823
middle, eight children,
and it ends up here even more

59:12.822 --> 59:14.672
then it was in 1950s.

59:14.670 --> 59:17.420
It has not changed.

59:17.420 --> 59:21.140
The fertility rate has not
responded to whatever it is

59:21.141 --> 59:25.071
about modern times and we'll
talk about it a lot what has

59:25.072 --> 59:27.322
caused fertility to go down.

59:27.320 --> 59:33.360
Now one thing you can say is
how many women don't want to

59:33.364 --> 59:38.014
have any more children,
and that, of course,

59:38.007 --> 59:43.187
depends on the number that you
already have.

59:43.190 --> 59:46.030
It gets up too--it starts women
have no children,

59:46.030 --> 59:49.230
very few, most of them want
children, and they have one

59:49.226 --> 59:51.116
child that's enough for two.

59:51.119 --> 59:54.329
At two children already you
have like 40% of women already

59:54.326 --> 59:56.516
saying, two children's enough
for me;

59:56.518 --> 59:59.318
again this is Morocco in the
Mediterranean zone.

59:59.320 --> 1:00:02.020
Then when you get up to six
children almost everybody says

1:00:02.023 --> 1:00:02.453
enough.

1:00:02.449 --> 1:00:08.079
The average for the whole
country is--that's like 53.3%.

1:00:08.079 --> 1:00:13.669
More than half of the women
say, okay no more children,

1:00:13.666 --> 1:00:20.076
and again this data is seven
years old, it's even lower now.

1:00:20.079 --> 1:00:25.339
You compare this to Mali and
this is the number of women that

1:00:25.335 --> 1:00:30.205
don't want any more children,
and I think the final there is

1:00:30.208 --> 1:00:32.588
8.6 or something,
an enormous difference.

1:00:32.590 --> 1:00:34.850
That no matter how many
children they have even--

1:00:34.849 --> 1:00:38.779
this is eight--six and more
children,

1:00:38.780 --> 1:00:42.060
still only a very few,
about a third of them say six

1:00:42.057 --> 1:00:46.127
or however many I have,
six and over is enough for me.

1:00:46.130 --> 1:00:58.700
This is in respect of those
two, you might say,

1:00:58.699 --> 1:01:04.509
well Niger is a very poor
country, Morocco is not anywhere

1:01:04.509 --> 1:01:07.759
near so poor,
it has something to do with

1:01:07.760 --> 1:01:08.840
infant mortality.

1:01:08.840 --> 1:01:12.890
This is indeed Morocco,
and look infant mortality has

1:01:12.889 --> 1:01:14.759
come down quite a bit.

1:01:14.760 --> 1:01:19.360
It's getting there and so you
say, oh well that's why

1:01:19.364 --> 1:01:21.914
Morocco--
Moroccan's want and have fewer

1:01:21.909 --> 1:01:24.839
children because they have a
better situation with infant

1:01:24.836 --> 1:01:29.036
mortality,
but then you look at Niger and

1:01:29.036 --> 1:01:31.926
not--
it's not as good as Morocco but

1:01:31.927 --> 1:01:36.247
it's still come down quite a bit
and since then it's come down

1:01:36.250 --> 1:01:37.030
further.

1:01:37.030 --> 1:01:41.770
You expect--well you'd see some
response in the fertility levels

1:01:41.766 --> 1:01:45.446
to that but you don't,
you don't see it at all.

1:01:45.449 --> 1:01:47.179
What's the difference?

1:01:47.179 --> 1:01:48.519
It's not religion.

1:01:48.518 --> 1:01:52.088
So both Niger and Morocco are
Sunni Muslim,

1:01:52.092 --> 1:01:56.602
and as far as I'm aware,
there's no big differences in

1:01:56.601 --> 1:02:00.091
the interpretation of religion
there.

1:02:00.090 --> 1:02:04.350
You see the same story in
Christian Sub-Saharan Africa

1:02:04.353 --> 1:02:05.323
countries.

1:02:05.320 --> 1:02:08.950
This is Tanzania,
again about the same years,

1:02:08.947 --> 1:02:13.727
and basically no change in
fertility--a little drop in very

1:02:13.728 --> 1:02:15.128
recent times.

1:02:15.130 --> 1:02:19.350
Zambia is coming up next,
in Zambia it's--even went

1:02:19.349 --> 1:02:24.499
higher and then it's down back
to where approximately where it

1:02:24.496 --> 1:02:25.506
started.

1:02:25.510 --> 1:02:26.580
This is characteristic.

1:02:26.579 --> 1:02:27.969
It's not a religious thing.

1:02:27.969 --> 1:02:31.659
There's something special about
Sub-Saharan Africa.

1:02:31.659 --> 1:02:35.489
Even South America doesn't look
like this at all.

1:02:35.489 --> 1:02:38.889
If you're in South America the
fertility is way,

1:02:38.885 --> 1:02:39.675
way down.

1:02:39.679 --> 1:02:43.949
There is something quite
special about Africa,

1:02:43.952 --> 1:02:49.652
and we're going to have to try
to figure out what that is.

1:02:49.650 --> 1:02:56.270
You'll read a really
interesting article by John

1:02:56.268 --> 1:03:04.858
Caldwell which talks about a
whole culture of reproduction.

1:03:04.860 --> 1:03:08.820
Again, Africa is a huge place,
has many different cultures and

1:03:08.820 --> 1:03:11.420
we're just talking Sub-Saharan
Africa.

1:03:11.420 --> 1:03:13.430
North Africa is a different
story;

1:03:13.429 --> 1:03:16.689
South Africa we have the
European settlement,

1:03:16.686 --> 1:03:21.196
that's another different story,
but the bulk of Central Africa

1:03:21.202 --> 1:03:23.352
to some degree fits this.

1:03:23.349 --> 1:03:26.599
You have places where you don't
have bad soil,

1:03:26.597 --> 1:03:30.637
so in the tropics Java has
volcanoes, volcanoes replenish

1:03:30.639 --> 1:03:31.289
soil.

1:03:31.289 --> 1:03:35.589
The mountain slopes of Kenya
have good soil from--again from

1:03:35.585 --> 1:03:36.745
volcanic soil.

1:03:36.750 --> 1:03:39.020
The stories there are a little
different.

1:03:39.018 --> 1:03:42.498
In general, we're talking about
those parts in Africa where it's

1:03:42.503 --> 1:03:46.203
hard to stay alive,
it's hard to get a population

1:03:46.202 --> 1:03:49.502
going that we're--
that places traditionally under

1:03:49.501 --> 1:03:52.251
populated and just now with
Western medicine are the

1:03:52.250 --> 1:03:55.270
population rates coming up to
where you might consider it

1:03:55.268 --> 1:03:55.968
crowded.

1:03:55.969 --> 1:03:59.989
A place like Nigeria now is
certainly crowded.

1:03:59.989 --> 1:04:08.679
In Africa, reproduction is at
the core of--the central core of

1:04:08.675 --> 1:04:11.805
traditional culture.

1:04:11.809 --> 1:04:15.839
Their religious ideas are all
tied in, very--essentially,

1:04:15.835 --> 1:04:19.715
with reproduction in the
lineage itself that means your

1:04:19.717 --> 1:04:21.297
line of ancestors.

1:04:21.300 --> 1:04:25.080
The prime duty of a human,
in this cultural setting,

1:04:25.083 --> 1:04:29.093
is to reproduce the lineage,
keep the lineage going.

1:04:29.090 --> 1:04:32.610
This is not at all unique to
Africa.

1:04:32.610 --> 1:04:36.370
In Indonesia I saw there was an
awful lot of this going on and

1:04:36.373 --> 1:04:38.783
I'll talk about other examples
of it.

1:04:38.780 --> 1:04:44.520
It's very pronounced in Africa
but not in any sense unique.

1:04:44.518 --> 1:04:47.638
The idea is that--one of the
ideas is that when a man dies he

1:04:47.639 --> 1:04:48.939
doesn't just disappear.

1:04:48.940 --> 1:04:51.980
We have a nice funeral service
and say bye-bye,

1:04:51.980 --> 1:04:55.300
and maybe once a year we come
and give flowers onto the grave,

1:04:55.300 --> 1:04:58.530
but we have no sense that that
person is still around.

1:04:58.530 --> 1:05:02.810
In these traditional parts of
the world the person lives on in

1:05:02.813 --> 1:05:06.473
kind of shadow world,
but he can communicate with his

1:05:06.465 --> 1:05:07.585
descendants.

1:05:07.590 --> 1:05:12.060
That's often not very
difficult, and he's dependent on

1:05:12.063 --> 1:05:14.853
his descendants for sustenance.

1:05:14.849 --> 1:05:17.989
If they don't feed him and give
him what he needs in the

1:05:17.992 --> 1:05:19.882
afterlife he is in big trouble.

1:05:19.880 --> 1:05:22.720
If a man does not have
descendants then he really

1:05:22.724 --> 1:05:24.864
doesn't get anything when he
dies.

1:05:24.860 --> 1:05:28.760
Again, I saw this in Bali
enormously, where there was

1:05:28.755 --> 1:05:32.795
enormous effort to bring
offerings to the recently dead

1:05:32.800 --> 1:05:33.850
ancestors.

1:05:33.849 --> 1:05:35.579
They're very,
very sensible about it.

1:05:35.579 --> 1:05:38.809
You see in Bali the women
carrying these--

1:05:38.809 --> 1:05:40.629
they're beautiful in their
beautiful dress,

1:05:40.630 --> 1:05:43.230
and they have these huge
platters on their heads filled

1:05:43.228 --> 1:05:46.258
with the most delicious fruits
and arranged just gorgeously,

1:05:46.260 --> 1:05:51.070
and they bring them to the
temple and the ancestors can

1:05:51.068 --> 1:05:53.748
partake of them,
and the next day they come and

1:05:53.751 --> 1:05:56.161
take it home and eat it,
because they understand that

1:05:56.155 --> 1:05:58.965
the ancestors are getting
spiritual not the physical

1:05:58.972 --> 1:05:59.472
stuff.

1:05:59.469 --> 1:06:02.989
So they leave it there and then
the ancestors can take what they

1:06:02.989 --> 1:06:04.739
get out of it,
and then the humans can take

1:06:04.737 --> 1:06:07.047
what they get out of it,
so it's not wasteful.

1:06:07.050 --> 1:06:10.530
Every store and every house
will have a little--every day a

1:06:10.530 --> 1:06:14.070
little thing out in the front
with a little bit of grain and

1:06:14.070 --> 1:06:14.970
everything.

1:06:14.969 --> 1:06:16.069
The dogs come by and eat it.

1:06:16.070 --> 1:06:19.110
Of course the dogs come by and
eat it, but that's okay.

1:06:19.110 --> 1:06:24.680
The ancestors have taken,
and the spirits have taken what

1:06:24.675 --> 1:06:27.055
they want out of this.

1:06:27.059 --> 1:06:34.219
In temperate zones we associate
religion and our culture--

1:06:34.219 --> 1:06:37.159
big empires,
big states, the United States

1:06:37.157 --> 1:06:41.597
is huge and any western country
population is large compared to

1:06:41.599 --> 1:06:45.109
say a Balinese Village or an
African Village.

1:06:45.110 --> 1:06:46.550
Religion is big.

1:06:46.550 --> 1:06:49.610
How many billions of Christians
are there, how many billions of

1:06:49.614 --> 1:06:51.694
Muslims are there,
of Buddhists and Hindus,

1:06:51.692 --> 1:06:53.722
we got everything--everything
is big.

1:06:53.719 --> 1:06:57.659
In Africa, in a sense,
each family's ancestors are its

1:06:57.657 --> 1:07:01.367
gods, and both traditional and
political authority,

1:07:01.371 --> 1:07:04.791
and religion are very,
very local affairs.

1:07:04.789 --> 1:07:06.989
They're not agglomerated into
big things.

1:07:06.989 --> 1:07:11.609
No one expects the people in
this village to worship the same

1:07:11.614 --> 1:07:14.394
as the people in the next
village.

1:07:14.389 --> 1:07:18.529
There isn't so much the idea of
a central monotheistic type of

1:07:18.525 --> 1:07:22.045
god which is--that comes up when
you have empires.

1:07:22.050 --> 1:07:24.790
You have a central emperor and
you have a central god.

1:07:24.789 --> 1:07:27.509
When you don't--when your
political thing is just your

1:07:27.505 --> 1:07:30.025
village,
again traditional times,

1:07:30.032 --> 1:07:34.142
there's no concept,
no need to have these either

1:07:34.143 --> 1:07:39.023
central political leaders versus
central religious gods.

1:07:39.018 --> 1:07:43.588
Immortality for you is provided
by your descendants.

1:07:43.590 --> 1:07:46.500
Immortality is very local;
it's your own descendants.

1:07:46.500 --> 1:07:50.300
That changes in Western
religion, especially in the

1:07:50.304 --> 1:07:52.974
Muslin Judeo-Christian
tradition.

1:07:52.969 --> 1:07:55.639
It's the religion,
it's God that gives you

1:07:55.637 --> 1:07:56.547
immortality.

1:07:56.550 --> 1:07:58.950
It's not your descendants,
so everybody's interested in

1:07:58.947 --> 1:08:01.287
immortality;
it's very important whether you

1:08:01.293 --> 1:08:03.243
go to heaven or hell and so
forth.

1:08:03.239 --> 1:08:06.889
The huge shift is whether it's
given to you by your

1:08:06.893 --> 1:08:09.253
descendants,
whether they take care of you

1:08:09.251 --> 1:08:10.861
and give you a kind of
immortality,

1:08:10.860 --> 1:08:13.880
or its given to you by your big
mega-religion,

1:08:13.880 --> 1:08:18.910
which tells you what you have
to do in order to gain

1:08:18.908 --> 1:08:20.288
immortality.

1:08:20.288 --> 1:08:22.258
When a person dies,
there again,

1:08:22.256 --> 1:08:24.856
they don't go off to a distant
heaven,

1:08:24.859 --> 1:08:28.129
they stay right locally and
gradually after a few

1:08:28.128 --> 1:08:31.938
generations they kind of
disappear into the mist and they

1:08:31.944 --> 1:08:34.264
have a very careful departure.

1:08:34.260 --> 1:08:37.350
Again, in Indonesia,
again comparing tropical

1:08:37.349 --> 1:08:41.769
regions, one of the big islands
is called Sulawesi or Celebes as

1:08:41.773 --> 1:08:44.023
we say in Western languages.

1:08:44.020 --> 1:08:47.100
Again, in many different
cultures, but in some of them a

1:08:47.103 --> 1:08:50.583
person dies, you don't want to
disturb that person because they

1:08:50.579 --> 1:08:52.149
can do bad stuff to you.

1:08:52.149 --> 1:08:55.819
You swaddle them;
he's going to rot,

1:08:55.819 --> 1:08:58.009
so you got problems,
you give him swaddling clothes

1:08:58.011 --> 1:09:00.901
and you sit him in a chair,
him or her, in a chair right in

1:09:00.903 --> 1:09:03.643
his own bedroom,
right where they live in houses

1:09:03.639 --> 1:09:05.559
sort of,
thatch houses,

1:09:05.564 --> 1:09:10.854
and they sit there for a long
time and gradually as they

1:09:10.849 --> 1:09:13.169
decay,
they smell, they take off the

1:09:13.171 --> 1:09:15.771
swaddling clothes,
get rid of that and swaddle

1:09:15.768 --> 1:09:18.408
them up again until they're down
to bones.

1:09:18.408 --> 1:09:20.218
And then they're taking up--so
they're not disturbed,

1:09:20.220 --> 1:09:21.960
by that time they're ready,
they don't have their flesh

1:09:21.963 --> 1:09:23.473
anymore,
they're ready to leave,

1:09:23.471 --> 1:09:26.681
so they take them to these big
cliffs overlooking the village,

1:09:26.680 --> 1:09:29.090
and there's caves,
natural caves in the cliff,

1:09:29.090 --> 1:09:31.210
and the dead bodies are brought
up there to sit,

1:09:31.210 --> 1:09:34.060
and look down over the village,
they're not very far away.

1:09:34.060 --> 1:09:36.510
It's really quite wonderful.

1:09:36.510 --> 1:09:41.610
I was in Bali stumbling around
under funny circumstances in a

1:09:41.606 --> 1:09:45.256
cemetery, and all these graves
were open.

1:09:45.260 --> 1:09:47.940
I said, what's going on are
they expecting--have they dug an

1:09:47.943 --> 1:09:50.403
awful lot of graves expecting
everybody to die soon?

1:09:50.399 --> 1:09:55.899
No, it turns out that a rich
man had just died.

1:09:55.899 --> 1:10:00.439
Now the poor people want to
provide for their ancestors in

1:10:00.435 --> 1:10:03.775
the next life but they don't
have money;

1:10:03.779 --> 1:10:07.169
they don't have any stuff,
so they bury him and they wait

1:10:07.167 --> 1:10:08.617
until a rich man dies.

1:10:08.618 --> 1:10:10.708
Then a rich man has this huge
procession.

1:10:10.710 --> 1:10:13.740
They're wonderful things to see
with big caskets,

1:10:13.738 --> 1:10:16.568
and big chariots,
and all this--just wonderful

1:10:16.565 --> 1:10:20.075
preparation and he's very rich
and the rich man's body is

1:10:20.082 --> 1:10:23.732
thrown into the ocean and all
kinds of stuff is thrown into

1:10:23.725 --> 1:10:27.365
the ocean to support this rich
man in his afterlife.

1:10:27.368 --> 1:10:29.758
Well, the poor people,
and it's quite okay because

1:10:29.762 --> 1:10:31.572
it's a very communal culture
Bali,

1:10:31.569 --> 1:10:34.809
very supportive of poor people,
they dig up their bodies,

1:10:34.810 --> 1:10:37.560
and they bring them in the same
time the rich man is put into

1:10:37.560 --> 1:10:38.110
the ocean.

1:10:38.109 --> 1:10:39.349
Poor people are put into the
ocean.

1:10:39.350 --> 1:10:42.070
They partake of all of this.

1:10:42.069 --> 1:10:44.109
What happens the next day,
of course the ocean--

1:10:44.109 --> 1:10:47.539
all the coins and what not have
come up on the beach and the

1:10:47.537 --> 1:10:50.407
rag-pickers,
the really poor people come by

1:10:50.405 --> 1:10:52.265
and collect all this stuff.

1:10:52.270 --> 1:10:56.610
It has--this cultural act of
burying the rich,

1:10:56.609 --> 1:11:00.409
not only does it equalize the
afterlife of the rich people and

1:11:00.407 --> 1:11:03.087
the poor people,
but the very poorest people who

1:11:03.085 --> 1:11:06.025
are still alive get some income
out of it as well as of course

1:11:06.027 --> 1:11:07.857
everybody who prepares the
funeral.

1:11:07.859 --> 1:11:10.889
It's a wonderful sort of way
that everything sort of hangs

1:11:10.894 --> 1:11:13.134
together as they usually do in
cultures.

1:11:13.130 --> 1:11:17.830
We will continue next time.

1:11:17.829 --> 1:11:22.999