The Great Filter

John K Clark (
Sun, 1 Sep 1996 08:51:57 -0700 (PDT)


On Sat, 31 Aug 1996 Anders Sandberg <> Wrote:

>We aren't that slow. We are not good sprinters, but our
>running endurance is much better than most animals

That's true, but I don't think bipedalism can claim credit for our good
endurance, it's because we're much better at getting rid of waste heat than
any other large mammal, and that's because we have sweat glands on every
part of our skin, and that's because we don't have a permanent coat of hair.
One of our first inventions must have been the coat, when it's cold we put it
on, when it gets hot we take it off, other animals must ware their coat all
the time. I doubt if Lucy was smart enough to make a coat, so she was probably
very harry and didn't have the endurance of modern humans. Then again, I would
have predicted that she would have a hand much inferior to ours, and I would
have been dead wrong about that, so who knows.

>Bipedalism gives us some tremendous advantages: the ability
>to see far over the savannah

Maybe, but if it means you can see a saber toothed tiger better over the tall
grass it also means that the saber toothed tiger can see you better too, and
he's a lot faster and tougher than you are. Anyway apes can walk for short
distances on 2 legs, long enough to get a good look at things if they want to,
no need to go to the ridiculous extreme we did.

>two free arms to throw rocks with and carry things.

Maybe, but apes can and do carry things in their arms without becoming
bipedal like us.

>My guess is that it emerged as we appeared on the east
>african savannahs, because of the die-backs of the forests
>we originally lived in.

Maybe, but it seems to me that bipedalism would be better in a dense jungle
than an open savanna where speed is all important. On the other hand it
evolved at a time when the climate was getting dryer, the jungle was
shrinking and the savanna was expanding. Go figure.

>Hands are perfect for gathering insects, seeds and other
>small but nutrient-rich sources of food.

But the hands of modern apes are good enough for that, they do it constantly,
but that's not what they're best at, they were optimized for locomotion.
Lucy using her delicate hand just to pick up bugs seems like tremendous
overkill to me, but maybe.

On Sat, 31 Aug 1996 "Kathryn Aegis" <> Wrote:

>we spent some time living along the shoreline and spending a
>great deal of time in the water. This would account for our
>upright posture, our relative lack of body hair

Maybe, but some of aquatic animals have a lot more hair than we do, beavers,
otters, seals. Being a biped is no advantage in swimming, many mammals are
much better at it than we are and they never came close to developing
anything like it. It might be a slight advantage in wading, but not much.
It's very difficult to walk in water over a foot deep for any distance,
almost impossible if it's over 2 feet deep, especially if you're only 4 and a
half feet tall as Lucy was. Anyway it's hard to see why a slight advantage in
wading would be important enough to justify such a radical change in body

Damien R. Sullivan On Sat, 31 Aug 1996 Wrote:

>> Clark
>>Why did Lucy have a hand capable of moving things
>>with precision when it doesn't look like she had a
>>brain good enough to take advantage of it? The first
>>very primitive tools appeared over a million years
>>after Lucy

>For throwing?

Maybe, William H Calvin wrote a book about this theory called "The Throwing
Madonna", I found it unconvincing. Following a moving object with your eyes
and then coordinating the muscles in your arm so that you can propel an
irregular shaped object at it takes split second timing and a lot of brain
power. Even modern humans would have a hard time making a living by throwing
baseballs at running animals, much less irregular rocks, and they have a much
bigger brain that Lucy did.

> [ maybe Lucy made ] Wooden spears or uncut rocks?

But a wooden spear would be harder to make than a simple stone tool, and
without bone or stone tools to help you, almost impossible to make. I don't
consider an uncut rock to be a tool, a tool needs to be made, but she may
have used rocks for something, although I have no idea for what.

John K Clark

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