I just heard that there is now evidence indicating that humans have evolved between 15 and 50 thousand years ago.
Bob

Human Evolution

I just heard that there is now evidence indicating that humans have evolved between 15 and 50 thousand years ago.
Bob

Re: Human Evolution

[quote author="Bob"]I just heard that there is now evidence indicating that humans have evolved between 15 and 50 thousand years ago.
Bob

:shock:

That seems VERY recent. Can you give further info about where this comes from? I’d be interested to know!

:shock:

Re: Human Evolution

[quote author="dougsmith"][quote author="Bob"]I just heard that there is now evidence indicating that humans have evolved between 15 and 50 thousand years ago.
Bob

shock

That seems VERY recent. Can you give further info about where this comes from? I’d be interested to know!

shock

Doug,
I reported that wrong. It was acually 5 to 15 thousand years ago.
I heard it on the New York Times radio station (WQXR) this evening. The story will be in tomorrow’s
New York Times.
Bob

Re: Human Evolution

[quote author="Bob"]Doug,
I reported that wrong. It was acually 5 to 15 thousand years ago.
I heard it on the New York Times radio station (WQXR) this evening. The story will be in tomorrow’s
New York Times.
Bob

Yeah, I saw the article this morning—on the front page no less! I think it was a bit overstated. Humans (Homo Sapiens Sapiens) evolved hundreds of thousands, maybe millions of years ago. Nothing in this article contradicted that point.

What they had discovered is that the human genome has been accumulating some slight modifications, most recently 5-15 thousand years ago. But none of these modifications are anything like speciation events, and it sounds like they were pretty subtle, except perhaps skin color. (If that really is so recent).

One other thing: these sorts of studies that rely on extrapolating backwards from present-day gene pools can be somewhat controversial unless backed up by independent evidence. We’ll see!

But very interesting anyhow.

Re: Human Evolution

Doug wrote
“What they had discovered is that the human genome has been accumulating some slight modifications, most recently 5-15 thousand years ago. But none of these modifications are anything like speciation events, and it sounds like they were pretty subtle, except perhaps skin color. (If that really is so recent).

One other thing these sorts of studies that rely on extrapolating backwards from present-day gene pools can be somewhat controversial unless backed up by independent evidence. We’ll see!”

Doug,
Yes, only slight modifications were discovered. And i expect there will be controversy about the findings.

i once took a course in human evolution at The AMNH and remember the instructor saying that we will continue to evolve indifinitely. I remember him saying that the back “needs a lot of work” because we weren’t meant to walk upright.
Bob

Re: Human Evolution

[quote author="Bob"]i once took a course in human evolution at The AMNH and remember the instructor saying that we will continue to evolve indifinitely. I remember him saying that the back “needs a lot of work” because we weren’t meant to walk upright.
Bob

Certainly, evolution never stops—there will always be selection forces favoring certain traits over others. But what is needed for radical evolutionary change (like speciation) is a small isolated population, where significant new traits can gain footholds and go to stasis relatively quickly. The huge human population and global system of transportation makes that nearly impossible now ... any new trait of any significance would likely be swamped by contact with too much competition, and getting more than one new trait going at a time in a small population is vanishingly improbable. So I would expect that human evolution from this point forward will likely be very slow and insignificant.

If we take something like Gould’s “punctuated equilibrium” to be correct, we are now at something of an “equilibrium”.

Spine

Bob:

You wrote: <i once took a course in human evolution at The AMNH and remember the instructor saying that we will continue to evolve indifinitely. I remember him saying that the back “needs a lot of work” because we weren’t meant to walk upright.>

There is just no question that the lumbar spine (back) “needs a lot of work.” The angle between the lowest lumbar vertebral body (L5) and the Sacrum clearly indicate a quadruped.  The inward sway in our lumbar spine (lordosis), the part that hurts and for which we design supports in our vehicles, is a product of that angle.  If I were to design a spine (intelligently) I certainly would have made the L5 to Sacrum angle much smaller.

The L5 to Sacrum angle is one of those bits of evidence (knowledge) that suggests ID did not happen.  The “design” is flawed biomechanically.  Note that the flaw does not make itself known until latter in life.  Generally after the child bearing years - go figure!  :D

Wes (PhD)
Director, Spine Biomechanics Laboratory
University of South Florida

Re: Spine

Wes wrote
“There is just no question that the lumbar spine (back) “needs a lot of work.” The angle between the lowest lumbar vertebral body (L5) and the Sacrum clearly indicate a quadruped.  The inward sway in our lumbar spine (lordosis), the part that hurts and for which we design supports in our vehicles, is a product of that angle.  If I were to design a spine (intelligently) I certainly would have made the L5 to Sacrum angle much smaller.

The L5 to Sacrum angle is one of those bits of evidence (knowledge) that suggests ID did not happen.  The “design” is flawed biomechanically.  Note that the flaw does not make itself known until latter in life.  Generally after the child bearing years - go figure!  D

Wes (PhD)
Director, Spine Biomechanics Laboratory
University of South Florida

Wes,
Thank you for your comments.
Bob

Re: Human Evolution

Doug wrote
“If we take something like Gould’s “punctuated equilibrium” to be correct, we are now at something of an “equilibrium"."

Wes.
I think you are right in saying we are now at something like an “equilibrium” and that we can only expect small changes in the future.

Thank you for your comments.
Bob

Re: Human Evolution

[quote author="dougsmith"][quote author="Bob"]Doug,
I reported that wrong. It was acually 5 to 15 thousand years ago.
I heard it on the New York Times radio station (WQXR) this evening. The story will be in tomorrow’s
New York Times.
Bob

Yeah, I saw the article this morning—on the front page no less! I think it was a bit overstated. Humans (Homo Sapiens Sapiens) evolved hundreds of thousands, maybe millions of years ago. Nothing in this article contradicted that point.

Wikipedia places the species Homo Sapiens as having evolved about 200 thousand years ago link .  Although I realize Wikipedia is certainly not infallible, since I don’t have a bet riding on this, I’m going to accept that answer for now.

Of course, Sapiens is just the “last step” in us becoming us, and of course this sentence is a gross misrepresentation of the nature of human evolution, evolution in general, and, oh yeah, nature. :D

There’s never a “last step” because evolution does not, or at least might not have, any clear goals as such.  Even if there were some sort of locus of goal conditions that evolution is converging towards, the process probably doesn’t really have “steps”.  There’s just this flow of genetic information from one generation to the next.  As the environment changes, so the frequency with which certain specific kinds/types/pieces of information are transfered changes.  Etc.

In contrast to the seeming intractability of comprehending the complexity of evolution, the rules for creating a catchy science headline in the newspaper are easy to grasp and deciminate:
1. Find a scientific paper that proposes an idea that’s new or that seems like it might be new
2. Grossly misrepresent and/or overestimate the paper’s claims.  For extra effect, put something in the headline like,
“NEW DISCOVERY!  BREAKS ALL KNOWN LAWS OF <X>!!!”

This trick will always work.

How could it ever possilby not work?  Even if you’re deeply skeptical of the headline’s claim, you still have to read it before you can attempt to debunk it.

Re: Human Evolution

PragmaticallyWyrd wrote
“Wikipedia places the species Homo Sapiens as having evolved about 200 thousand years ago link.  Although I realize Wikipedia is certainly not infallible, since I don’t have a bet riding on this, I’m going to accept that answer for now. )”

PragmaticallyWyrd,
I believe that wikipedia is correct about the that. Archaic Homo sapiens evolved about then.
Bob
------

PragmaticallyWyrd continues
“There’s never a “last step” because evolution does not, or at least might not have, any clear goals as such.  Even if there were some sort of locus of goal conditions that evolution is converging towards, the process probably doesn’t really have “steps”.  There’s just this flow of genetic information from one generation to the next.  As the environment changes, so the frequency with which certain specific kinds/types/pieces of information are transfered changes.  Etc.”

PragmaticallyWyrd,
That seems accurate to me.

Thank you for your comments.
Bob

Re: Human Evolution

[quote author="Bob"]I just heard that there is now evidence indicating that humans have evolved between 15 and 50 thousand years ago.
Bob

Neat.  we just keep getting better and better.!!  Opps, maybe that was the religion gene that developed and its really de-evolving.

You never know.

Elder Norm

Our link with Homo erectus?

A skull found recently in Ethiopia could be the link between anatomically modern Homo sapiens and Homo erectus. The skull is between 200,000 and 500,000 years old. It has characteristics of both Homo sapiens and Homo erectus. If it is as old as 500,000 years it would probably indicate that we evolved much earlier than we thought--perhaps as much as 300,000 years earlier.
The fossil was found in the Afar region of Ethiopia by archaeologists.
Bob

Re: Our link with Homo erectus?

[quote author="Bob"]A skull found recently in Ethiopia could be the link between anatomically modern Homo sapiens and Homo erectus. The skull is between 200,000 and 500,000 years old.
Bob

Well, that’s awesome.  Have you maybe got, like, some links or something?

TIA

Re: Our link with Homo erectus?

[quote author="PragmaticallyWyrd"][quote author="Bob"]A skull found recently in Ethiopia could be the link between anatomically modern Homo sapiens and Homo erectus. The skull is between 200,000 and 500,000 years old.
Bob

Well, that’s awesome.  Have you maybe got, like, some links or something?

TIA

PragmaticallyWyrd,

Here’s a link http/www.nytimes.com/APonline/-international/adEthiopia-Ancient-Skull

Bob