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Kiwon
08-09-2007, 03:54 AM
For all you monkey lovers out there.....it's time to redraw the ole Evolutionary timeline using an Etch-A-Sketch.

Shock! Homo Habilis and Homo Erectus were homies. Well, at least, Homo Erectus (I love the name :D ) was cool. He was a playa'!
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Skull Suggests Two Early Humans Lived at Same Time

(AP) Wednesday, August 08, 2007

Surprising fossils dug up in Africa are creating messy kinks in the iconic straight line of human evolution with its knuckle-dragging ape and briefcase-carrying man.

The new research by famed paleontologist Meave Leakey in Kenya shows our family tree is more like a wayward bush with stubby branches, calling into question the evolution of our ancestors.

The old theory was that the first and oldest species in our family tree, Homo habilis, evolved into Homo erectus, which then became us, Homo sapiens.

But those two earlier species lived side-by-side about 1.5 million years ago in parts of Kenya for at least half a million years, Leakey and colleagues report in a paper published in Thursday's journal Nature.

In 2000 Leakey found an old H. erectus complete skull within walking distance of an upper jaw of the H. habilis, and both dated from the same general time period.

That makes it unlikely that H. erectus evolved from H. habilis, researchers said.

It's the equivalent of finding that your grandmother and great-grandmother were sisters rather than mother-daughter, said study co-author Fred Spoor, a professor of evolutionary anatomy at the University College in London.

The two species lived near each other, but probably didn't interact with each other, each having their own "ecological niche," Spoor said.

Homo habilis was likely more vegetarian and Homo erectus ate some meat, he said.

Like chimps and gorillas, "they'd just avoid each other, they don't feel comfortable in each other's company," he said.

They have some still-undiscovered common ancestor that probably lived 2 million to 3 million years ago, a time that has not left much fossil record, Spoor said.

Overall what it paints for human evolution is a "chaotic kind of looking evolutionary tree rather than this heroic march that you see with the cartoons of an early ancestor evolving into some intermediate and eventually unto us," Spoor said in a phone interview from a field office of the Koobi Fora Research Project in northern Kenya.

That old evolutionary cartoon, while popular with the general public, keeps getting proven wrong and too simple, said Bill Kimbel, who praised the latest findings.

He is science director of the Institute of Human Origins at Arizona State University and wasn't involved in the research team.

"The more we know, the more complex the story gets," he said.

Scientists used to think H. sapiens evolved from Neanderthals, a closely related species, he said, but now know that both species lived during the same time period and that we did not come from Neanderthals.

Now a similar discovery applies further back in time.

Leakey's team spent seven years analyzing the fossils before announcing their findings that it was time to redraw the family tree — and rethink other ideas about human evolutionary history, especially about our most immediate ancestor, H. erectus.

Because the H. erectus skull Leakey recovered was much smaller than others, scientists had to first prove that it was erectus and not another species nor a genetic freak.

The jaw, probably from an 18- or 19-year-old female, was adult and showed no signs of any type of malformations or genetic mutations, Spoor said. The scientists also know it isn't H. habilis from several distinct features on the jaw.

That caused researchers to re-examine the 30 other erectus skulls they have and the dozens of partial fossils.

They realized that the females of that species are much smaller than the males — something different from modern man, but similar to other animals, said study co-author Susan Anton, a New York University anthropologist.

Scientists hadn't looked carefully enough before to see that there was a distinct difference in males and females.

Difference in size between males and females seem to be related to monogamy, the researchers said.

Primate species that have same-sized males and females, such as gibbons, tend to be more monogamous. Species that are not monogamous, such as gorillas and baboons, have much bigger males.

This suggests that our ancestor H. erectus reproduced with multiple partners.

The H. habilis jaw was dated at 1.44 million years ago. That is the youngest ever found from a species that scientists originally figured died off somewhere between 1.7 and 2 million years ago, Spoor said. It enabled scientists to say that H. erectus and H. habilis lived at the same time.

All the changes to human evolutionary thought should not be considered a weakness in the theory of evolution, Kimbel said. Rather, those are the predictable results of getting more evidence, asking smarter questions and forming better theories, he said.

Kiwon
08-09-2007, 04:51 AM
More fun with monkeys....

"The more we know, the more complex the story gets," he said.

Scientists used to think H. sapiens evolved from Neanderthals, a closely related species, he said, but now know that both species lived during the same time period and that we did not come from Neanderthals.

(Old assumption proven wrong)

Now a similar discovery applies further back in time.

Leakey's team spent seven years analyzing the fossils before announcing their findings that it was time to redraw the family tree — and rethink other ideas about human evolutionary history, especially about our most immediate ancestor, H. erectus.

"Because the H. erectus skull Leakey recovered was much smaller than others, scientists had to first prove that it was erectus and not another species nor a genetic freak.

The jaw, probably from an 18- or 19-year-old female, was adult and showed no signs of any type of malformations or genetic mutations, Spoor said. The scientists also know it isn't H. habilis from several distinct features on the jaw.

That caused researchers to re-examine the 30 other erectus skulls they have and the dozens of partial fossils.

They realized that the females of that species are much smaller than the males — something different from modern man, but similar to other animals, said study co-author Susan Anton, a New York University anthropologist.

Scientists hadn't looked carefully enough before to see that there was a distinct difference in males and females.

Difference in size between males and females seem to be related to monogamy, the researchers said.

Primate species that have same-sized males and females, such as gibbons, tend to be more monogamous. Species that are not monogamous, such as gorillas and baboons, have much bigger males.

This suggests that our ancestor H. erectus reproduced with multiple partners.

(Differences in skull sizes. Hmmmm....Let's make a new assumption. Homo erectus was a horny critter, a real playa'.)

The H. habilis jaw was dated at 1.44 million years ago. That is the youngest ever found from a species that scientists originally figured died off somewhere between 1.7 and 2 million years ago, Spoor said. It enabled scientists to say that H. erectus and H. habilis lived at the same time.

All the changes to human evolutionary thought should not be considered a weakness in the theory of evolution, Kimbel said. Rather, those are the predictable results of getting more evidence, asking smarter questions and forming better theories, he said."
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Sorry, Dr. K. All the changes to human evolutionary thought ARE a weakness in the theory of evolution. There is no other reasonable way to evaluate it.

Bias in Science? No way! Science is based solely on fact and reason! (But, in this case, we don't have evidence for our theory but that doesn't matter. Our theory just HAS to be true!"

Yes, and Elvis is playing in nightclubs on Pluto. Just wait.....you'll see....the evidence will come.

Kiwon
08-09-2007, 05:05 AM
These are my favorite Monkees. I wonder who is Homo Erectus? :D

http://upload.wikimedia.org/wikipedia/en/f/f1/Monkees1967.jpg

Kiwon
08-09-2007, 05:48 AM
http://news.nationalgeographic.com/news/bigphotos/images/060308_all_fours_big.jpg

Whatever happened to these "missing links?"
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Family Walks on All Fours, May Offer Evolution Insight, Experts Say

James Owen in London for National Geographic News
March 8, 2006

Five adult siblings who can walk only on all fours have been found in Turkey, researchers say. These human quadrupeds may provide clues to how humans evolved to stand on two feet.

The three sisters and two brothers may offer insight into the way our apelike ancestors moved, according to scientists. Human ancestors are believed to have begun walking on two legs more than three million years ago.

Discovered in a remote area of southern Turkey last summer, the family of ethnic Kurds has sparked a scientific debate, which will be covered in a BBC television documentary that is set to air on March 17 in the United Kingdom. The family's exact location and last name have not been disclosed.

Born with a genetic brain abnormality, two of the sisters and one of the brothers are thought to have only walked on all fours their entire lives. The two other siblings can walk upright for short distances.

The siblings' parents are closely related and have had 19 children in all.

This bizarre case is not a hoax, according to experts who have studied the family.

The cause of the four-limbed locomotion, however, is a bone of contention among the researchers.

Uner Tan is a neurophysiologist—a doctor specializing in the functions of the brain, spinal cord, and nerves—at Cukurova University in Adana, Turkey.

He believes the siblings, who range in age from 18 to 34, are evolutionary throwbacks—a "missing link" to our forebears.

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