Darwinian Package

"Representative Trantis" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Don't know if this is appropriate for evolution, and should be posted to anthropology, but I will
post it here anyway, and let the moderators

decide.

Quoted message said:

Darwin proposed the idea of human evolution as a package, with bipedalism, technology and
intelligence/a large brain, all came together. Today we know that isn't true. There is a rather
large gap between bipedalism and the emergence of intelligence and technology, certainly enough
for it not to be a package.

Human females have a rather difficult time giving birth, that's a little bit of an understatement!
This is because we first evolved bipedal locomotion, requiring narrow hips.

I tried to find something on the 'net about the narrow-hip requirement, but couldn't. Could you
briefly explain or point me to a source (... seems counter-intuitive to me). .

Quoted message said:

We then developed bigger brains. This obviously requires a bigger head. Humans however, having a
narrow pelvis, can only stay in for nine months before they are only just large enough to still
enable them to fit the head through the pelvis. Consequently we come out much earlier than we
should for our optimal brain development. This is one of the major theories as to why human babies
are so helpless for their first year.

It seems to me, that if you accept the general view that organisms can't evolve into anything less
fit, in order to get fitter, they can't go down the slope of mount improbable to get further up in
the long run as one famous Zoologist would put it. Then something stares you in the face.

This something (I finally get to the point) is that it seems clear that bipedalism evolved first,
and that the intelligence developed later, having to simply make do with what it has, ie, an
inadequatly narrow pelvis for such a large brain/skull.

You've lost me... this seems like circular reasoning. My reading in your second paragraph is that
"we first evolved bipedal locomotion" - I take it you mean "first" in relation your next statement -
"we then delevoped bigger brains", and from this you conclude that "it seems clear that bipedalism
evolved first, and that the intelligence developed later". Clearly if the former is correct the
latter is also, as they are identical. Your point seems straightforward - I just seem to be missing
how you got there. Hopefully others responding will make this evident to me, but if not, please try
rephrasing your reasoning.

FWIW, I think there's some validity in your point, although it's not as black and white (first
bipedalism and then a larger brain) in my view, mainly because brain size increased over some 7-9
million years (or, in reality, far, far longer within ancestor species), while bipedalism was more
of a one-time shot. My understanding, based on albeit limited knowledge of the fossil record, is
that bipedalism developed some 6 million years ago (I may well be wrong here but hope I'm in the
ball park), but as noted, brain size had already been increasing and would continue to do so until
about 130,000 years ago. To me, that partly means your "emergence of intelligence" statement is
misleading - intelligence was not totally absent 5, 10 or 15 mya, and is almost certainly, IMHO, not
a completed fact now - intelligence should be placed on a curve as opposed to being absent or
present (inanimate objects, possibly fungi and vegetation, and certain individuals I've met ;-)
excepted). Your entire phrase "emergence of intelligence and technology" is even more misleading, in
that basic intelligence of [censored] sapiens sapiens emerged with species emergence (~.13 mya), while
technology has been developing for some 3 million years or more, with several obvious spikes over
that entire period. This has accelerated over the last ~10K years, especially so over the past ~300
years, and is somewhat mind-boggling today. But acceleration will likely increase far beyond what we
can now imagine, assuming we don't wipe ourselves out or similar. Hope that hasn't muddied the
waters unacceptabley.

Finally, I'll question your taking only two points (biped. and brain/intelligence) and comparing it
any "package". What about opposing thumbs or forward-looking eyes, for example?

Quoted message said:

For me this seems to stare you in the face. Why wasn't this picked up upon much earlier? (Or am I
missing something about the specifics of the anatomical requirements of bipedalism in
apes/humans? )

Best regards, Brett.

In a post sent 2 hours ago I suggested bipedalism at ~6 mya and technology (tools) starting at ~ 3
mya. After a closer look it would seem more accurate to say ~5.6 mya and 2.6 mya, respectively,
though I'd think both are still open to change. Regards, Brett.

Representative Trantis said:

Don't know if this is appropriate for evolution, and should be posted to anthropology, but I will
post it here anyway, and let the moderators decide.

Darwin proposed the idea of human evolution as a package, with bipedalism, technology and
intelligence/a large brain, all came together. Today we know that isn't true. There is a rather
large gap between bipedalism and the emergence of intelligence and technology, certainly enough
for it not to be a package.

Human females have a rather difficult time giving birth, that's a little bit of an understatement!
This is because we first evolved bipedal locomotion, requiring narrow hips. We then developed
bigger brains. This obviously requires a bigger head. Humans however, having a narrow pelvis, can
only stay in for nine months before they are only just large enough to still enable them to fit
the head through the pelvis. Consequently we come out much earlier than we should for our optimal
brain development. This is one of the major theories as to why human babies are so helpless for
their first year.

It seems to me, that if you accept the general view that organisms can't evolve into anything less
fit, in order to get fitter, they can't go down the slope of mount improbable to get further up in
the long run as one famous Zoologist would put it. Then something stares you in the face.

This something (I finally get to the point) is that it seems clear that bipedalism evolved first,
and that the intelligence developed later, having to simply make do with what it has, ie, an
inadequatly narrow pelvis for such a large brain/skull.

For me this seems to stare you in the face. Why wasn't this picked up upon much earlier? (Or am I
missing something about the specifics of the anatomical requirements of bipedalism in
apes/humans? )

I don't see any problem here. There used to be two competing ideas in anthropology. The
presapient guys and the recent evolution guys. The guys that fell for the Piltdown hoax were
among the presapient group. They argued that the brain was the first thing to develop and that it
did a very long time ago. The guys that were going with the fossils like the australopithicines
from South Africa were claiming that there were small brained bipeds just 3 or 4 million years
ago. The molecular data started to back up the recent evolution contingent, and Lucy pretty much
nailed the fact that bipedalism preceded the large brain, but you have to figure that ape brains
had been getting bigger for millions of years before bipedalism. Lucy's brain was much larger
than a monkey's.

There is the fact that the human male pelvis is much more constricted than the female pelvis and
this is due to the fact that the birth canal bequeathed by our quadraped ancestors had the birth
canal pass through the pelvis. If we gave birth just below the belly button there is no telling how
large our heads would be. The male structure may be more efficient for bipedal locomotion and
females are stuck with

difference in the way the hips sway. Some people think that the female opening is about as wide as
it can be and maintain useful stability. I've never seen any real numbers on this, but it is

structure was optimal the males would have the same structure.

There is no problem here. The female pelvis had to evolve to accomodate the increasing brain size.
Neandertals would have had a bigger problem than modern humans, and australopithicines would have
had less of a problem. This is an example of canalization. Modern human evolution was limited by the
bipedal hip structure, and the position of the birth canal. Evolving larger brains entailed smaller
and less developed brains at birth and longer post natal development times. If I were to guess I'd
say that child rearing requirements was one of the selective agents for higher brain functions and
increasing brain size of that larger brain. You have to be smarter to raise the larger brained
offspring that in turn can do more with their brains. It could be one of the ratchets that made us
so smart, or at least seemingly smarter than we would need to be to survive.

Ron Okimoto

"Representative Trantis" <[email hidden]> wrote in message

Quoted message said:

There is a rather large gap between bipedalism and the emergence of intelligence and technology,
certainly enough for it not to be a package.

There's a large gap between bipedalism and big braincases and worked stone tools. This doesn't mean
that there wasn't some increase in intelligence and the use of primitive tools, maybe driving
bipedalism.

Quoted message said:

It seems to me, that if you accept the general view that organisms can't evolve into anything less
fit, in order to get fitter, they can't go down the slope of mount improbable to get further up in
the long run as one famous Zoologist would put it.

An organism can't preadapt. Humans can't become bipedal because free hands will be useful in a
million years when they develop technology. There has to be an immediate advantage.

Quoted message said:

Then something stares you in the face.

This something (I finally get to the point) is that it seems clear that bipedalism evolved first,
and that the intelligence developed later, having to simply make do with what it has, ie, an
inadequatly narrow pelvis for such a large brain/skull.

It's pretty obvious that high intelligence was such a powerful selective advantage that even a high
death rate in childbirth and over a year's helplessness as an infant was tolerated as the price.

Quoted message said:

For me this seems to stare you in the face. Why wasn't this picked up >

upon much earlier? (Or am I missing something about the specifics of

Quoted message said:

theanatomical requirements of bipedalism in apes/humans? )

Hominid fossils are quite rare, and Darwin had no way of knowing how quickly intelligence had
evolved. There is tendency to assume that organisms are perfectly adapted to the environment they
find themselves in. Human babies show that there can be developmental constraints, and if parents
can provide a lot of protection to an infant then selection will only very slowly act to make them
less helpless.

"Ron Okimoto" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Representative Trantis said:

Don't know if this is appropriate for evolution, and should be posted to anthropology, but I
will post it here anyway, and let the moderators

decide.

Quoted message said:

Quoted message said:

Darwin proposed the idea of human evolution as a package, with

bipedalism,

Quoted message said:

Quoted message said:

technology and intelligence/a large brain, all came together. Today we

know

Quoted message said:

Quoted message said:

that isn't true. There is a rather large gap between bipedalism and the emergence of
intelligence and technology, certainly enough for it not to

be

Quoted message said:

Quoted message said:

a package.

Human females have a rather difficult time giving birth, that's a little

bit

Quoted message said:

Quoted message said:

of an understatement! This is because we first evolved bipedal

locomotion,

Quoted message said:

Quoted message said:

requiring narrow hips. We then developed bigger brains. This obviously requires a bigger head.
Humans however, having a narrow pelvis, can only stay in for nine months before they are only
just large enough to still enable them to fit the head through the pelvis. Consequently we come
out much earlier than we should for our optimal brain development. This is

one

Quoted message said:

Quoted message said:

of the major theories as to why human babies are so helpless for their

first

Quoted message said:

Quoted message said:

year.

It seems to me, that if you accept the general view that organisms can't evolve into anything
less fit, in order to get fitter, they can't go

down

Quoted message said:

Quoted message said:

the slope of mount improbable to get further up in the long run as one famous Zoologist would
put it. Then something stares you in the face.

This something (I finally get to the point) is that it seems clear that bipedalism evolved
first, and that the intelligence developed later,

having

Quoted message said:

Quoted message said:

to simply make do with what it has, ie, an inadequatly narrow pelvis for such a large
brain/skull.

For me this seems to stare you in the face. Why wasn't this picked up

upon

Quoted message said:

Quoted message said:

much earlier? (Or am I missing something about the specifics of the anatomical requirements of
bipedalism in apes/humans? )

I don't see any problem here. There used to be two competing ideas in anthropology. The presapient
guys and the recent evolution guys. The guys that fell for the Piltdown hoax were among the
presapient group. They argued that the brain was the first thing to develop and that it did a very
long time ago. The guys that were going with the fossils like the australopithicines from South
Africa were claiming that there were small brained bipeds just 3 or 4 million years ago. The
molecular data started to back up the recent evolution contingent, and Lucy pretty much nailed the
fact that bipedalism preceded the large brain, but you have to figure that ape brains had been
getting bigger for millions of years before bipedalism. Lucy's brain was much larger than a
monkey's.

There is the fact that the human male pelvis is much more constricted than the female pelvis and
this is due to the fact that the birth canal bequeathed by our quadraped ancestors had the birth
canal pass through the pelvis. If we gave birth just below the belly button there is no telling
how large our heads would be. The male structure may be more efficient for bipedal locomotion and
females are stuck with

Quoted message said:

difference in the way the hips sway. Some people think that the female opening is about as wide as
it can be and maintain useful stability. I've never seen any real numbers on this, but it is

Quoted message said:

structure was optimal the males would have the same structure.

There is no problem here. The female pelvis had to evolve to accomodate the increasing brain size.
Neandertals would have had a bigger problem than modern humans, and australopithicines would have
had less of a problem. This is an example of canalization. Modern human evolution was limited by
the bipedal hip structure, and the position of the birth canal. Evolving larger brains entailed
smaller and less developed brains at birth and longer post natal development times. If I were to
guess I'd say that child rearing requirements was one of the selective agents for higher brain
functions and increasing brain size of that larger brain. You have to be smarter to raise the
larger brained offspring that in turn can do more with their brains. It could be one of the
ratchets that made us so smart, or at least seemingly smarter than we would need to be to survive.

Ron Okimoto

You've raised an interesting issue here, that the birth canal is through the pelvis, this arising
from quadrapedal ancesters. Why did they evolve this way?, if I had to make an educated guess I
would say that it is because it is easier to mount a quadrapedal animal from behind rather than get
underneath her, and that as a consequence of this, the female's reproductive organs are at the back,
through the pelvis to accomodate this.

Am I correct in saying that?

"Representative Trantis" <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

"Ron Okimoto" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

SNIP:

Quoted message said:

You've raised an interesting issue here, that the birth canal is through the pelvis, this arising
from quadrapedal ancesters. Why did they evolve this way?, if I had to make an educated guess I
would say that it is because it is easier to mount a quadrapedal animal from behind rather than
get underneath her, and that as a consequence of this, the female's reproductive organs are at the
back, through the pelvis to accomodate this.

Am I correct in saying that?

It is probably an accident of how the hips formed in the first terrestrial vertebrates and the use
of the same rear opening for egg laying that fish had. There could be support and attachment reasons
so that the organs could be supported in a terrestrial environment, you don't want them dangling and
subject to injury. When this arrangement evolved the egg size was small relative to body size and
the eggs did not have hard shells until reptiles evolved.

Ron Okimoto