189 replies to this topic

[PainBrush]

I searched & couldn't find any chimp & corndog pics online .

[Ironhand]

How 'bout a pic of Bush eating a corndog?

[Ironhand]

April 12, 2007 > China's earliest human puts 'out of Africa' theory to test

China's earliest human puts 'out of Africa' theory to test

By Neil Schoenherr

Researchers at WUSTL and the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing have been studying a 40,000-year-old early modern human skeleton found in China and have determined that the "out of Africa" dispersal of modern humans may not have been as simple as once thought.
The research was published April 3 in the Proceedings of the National Academy of Sciences.

Erik Trinkaus, Ph.D., the Mary Tileston Hemenway Professor of anthropology in Arts & Sciences, with colleague Hong Shang and others at the IVPP examined the skeleton, recovered in 2003 from the Tianyuan Cave, Zhoukoudian, near Beijing City.

The skeleton dates to 38,500-42,000 years ago, making it the oldest securely dated modern human skeleton in China and one of the oldest modern human fossils in eastern Eurasia.

The find could help explain how early man moved east across Europe and Asia, a movement not completely understood by anthropologists.

The "out of Africa" theory proposes that modern humans evolved in Africa and then spread throughout the earth around 70,000 years ago, replacing earlier humans with little or no interbreeding.

The specimen is basically a modern human, but it does have a few archaic characteristics, particularly in the teeth and hand bones.

This morphological pattern implies that a simple spread of modern humans from Africa is unlikely, especially because younger specimens have been found in eastern Eurasia with similar feature patterns, Trinkaus said.

"The discovery promises to provide relevant paleontological data for our understanding of the emergence of modern humans in eastern Asia," the researchers said.

They argue that the most likely explanation for the mix of features is interbreeding between early modern humans and the archaic populations of Europe and Asia.

[Kortoso]

A possible evolution from Java Man and Peking Man?

[deuce]

The "Out of Africa" vs "Out of Asia" question still isn't settled.

[Ironhand]

We're not going to see an answer to this question anytime soon. But it's interesting to watch the anthropologists slug it out.

[Kortoso]

Stop me if you're heard this one:
Neanderthal flute?

[Ironhand]

Ape gestures 'show human links'

Researchers in the US say they have firm evidence that apes communicate using gestures - shedding light on the development of human language.
The team analysed the way bonobos and chimpanzees used hand and limb gestures to make themselves understood.

The scientists found the apes used gestures more flexibly than the way they used facial and vocal expressions.

They say the findings support the theory that human language developed through the use of hand gestures.

Food or sex?

The team comprised researchers from Yerkes Primate Center, at Emory University in Atlanta, Georgia. It found ape groups developed different gestures to say different things and that meanings depended on context.

They may use the same gesture for something totally different

A male chimpanzee may beg for food from another chimpanzee by gesturing with an extended arm and open hand.

But the same gesture might also be used to ask a female chimpanzee for sex, or between two males as a sign of reconciliation after a fight, said primatologist Frans de Waal, a member of the research team.

"Typically they may use it for food... but they may use the same gesture for something totally different; so, for instance, a male may invite a female for sex by holding out an open hand to her," Dr de Waal said.

This ability to learn gestures distinguishes apes from monkeys and most other species on the planet, the scientist says.

Although all primates use vocal and facial expressions to communicate, only the great apes - chimpanzees, bonobos, orang-utan and gorillas - use gestures as well, an ability they share with humans.

And when apes gesture, they use their right hand, which is controlled by the left side of the brain - the same side as the language control centre in the human brain.

The latest research is published in the Proceedings of the National Academy of Sciences.

Edited by Ironhand, 08 May 2007 - 10:34 AM.

[VoragoExcarnator]

It seems to me that the Out of Africa vs. Out of Asia question has been firmly settled in the favor of Out of Africa. I know it rubs people the wrong way (we're related to negroes? the horror!!) but there seems to be a strongly established consensus in favor of the Out of Africa theory. Note that even proponents of the multiregional hypothesis concede that modern humans first arose in Africa (the main point of contention is: did modern humans displace earlier hominids living in Eurasia/elsewhere, or interbreed with them). There is no real scientific debate over whether modern humans arose in Africa!!! The polygenic evolution theory is wholly discredited:

From wiki: "An older theory is Polygenic evolution, a multiple origins theory in which the different human populations or races had independent origins and evolved in isolation from each other. Held by many scholars of the 19th century such as Haeckel and Klaatsch, and even some of the 20th, such as Carleton S. Coon, it is biologically impossible since all populations of a species must have the same, single origin. Polygenism is sometimes mistaken for Multiregional evolution, because they are both hypotheses of evolution within a single species. However, Polygenic evolution depends on isolation of populations while Multiregional evolution requires population interactions and interbreeding so that genetic changes can spread throughout the human range, especially when they are promoted by natural selection. According to the Multiregional hypothesis, geographic differences between human populations are the results of climatic variation, isolation by distance, and historical accidents (genetic drift)."

Wikipedia has a pretty good summary.
http://en.wikipedia....igin_hypothesis

There is certainly still debate about the origin of man, no doubt about it. But modern humans arose in Africa, also no doubt about it. Cheers.

[Ironhand]

A new discovery concerning the common ancestor to monkeys, apes, and men.

Jeanna Bryner
LiveScience Staff Writer
LiveScience.com
Mon May 14, 8:15 PM ET

Higher primates such as humans are considered the brainiacs of the mammalian world. But a 29-million-year-old fossilized skull suggests that one of our remote ancestors was a bit of a ?pea brain,? sporting a noggin smaller than that of a modern lemur.

The skull belonged to a common ancestor of humans, monkeys and apes.

"This means the big-brained monkeys and apes developed their large brains at a later point in time,? said lead study author Elwyn Simons, a Duke University primatologist.

Until now, scientists had assumed brain size was a key feature that defined higher primates, a category that includes humans, monkeys and apes. The larger brain relative to body size also has provided paleoanthropologists with a physical marker for the evolutionary distinction between higher and lower primates, which include lemurs of Madagascar.

Tiny enough to fit into the palm of your hand, the skull comes from a female Aegyptopithecus zeuxis, which means ?linking Egyptian ape.? This early monkey lived about 33 million years ago, a time when primates were evolving rapidly. The cat-size primate ate fruits and leaves in a tropical rainforest in what is now the Fayum in Egypt.

The discovery, published online this week in the journal Proceedings of the National Academy of Sciences, sheds light on the evolution of human-like brains .

?The reason Aegyptopithecus is so important is that it?s at the base of the family tree of the Old World higher primates, the group that we?re in,? Simons told LiveScience. ?So this is telling us something about the chapter in our own ancestry.?

Small minded

Simons and his team dug up the skull in 2004 from a quarry called the Jebel Qatrani Formation in Egypt. The cranium was so well preserved the team used micro computed-tomography (CT) scanning, which relies on X-rays, to recreate the inside of the skull and calculate dimensions of the brain it once encased.

He had found a similar, but fragmented skull at the site in 1966. Comparing dimensions of the old and new skull suggests the 1996 specimen belonged to a male, while the new skull was that of a female. The size of the female skull suggests it ?had a brain that might have been even smaller than that of a modern lemur's," Simons said.

The new skull also suggests the species had a much smaller brain than was previously estimated based on the 1996 skull.

?It?s a little surprising to find out that the brain volume on this thing indicates that maybe the New and Old World monkeys, their common ancestor had a prosimian-, or lower-primate-like brain like Aegyptopithecus does,? Simons said.

Sex differences

The team estimates the female weighed about five and a half pounds, or half the weight of the male. This size difference between males and females, called ?sexual dimorphism,? is comparable to that in gorillas, whose genes make them our second-closest relatives next to chimpanzees.

The stark size difference indicates the monkey-like animals were social and hung out in multi-male and multi-female troops of 15 to 20 individuals. ?If we infer that an Aegyptopithecus had a large social group, that suggests it had enough sense to tell all of those members apart from nonmembers,? Simons said.

"But other features in these skulls, and in many other Aegyptopithecus fossil pieces collected at the Egyptian site over four decades, suggest that this primate was already branching away from its lemur-like ancestry," he said.

Other features also point to an evolving primate. The skull shows features similar to other higher primates, including a developed visual cortex, suggesting Aegyptopithecus had acute vision. "So the visual sense, which is regarded as a very important feature of anthropoids, or higher primates, had already expanded,? Simons said.

And unlike the prosimians, which run around at night, the animal had small eye sockets and was likely diurnal (awake during daylight) like modern and ancient higher primates.

[deuce]

Cool article. Thanks, Ironhand.

[PainBrush]

The size of the female skull suggests it ?had a brain that might have been even smaller than that of a modern lemur's , " Simons said .

Hmmm , very interesting !


I have my long awaited well-phrased comeback to that ages old 'male knuckledraggers' insult , & from a scientist no less ! I'm considering adding that quote to my favorites in my signature .

Edited by PAINBRUSH, 16 May 2007 - 12:19 AM.

[Ironhand]

Fossils challenge old evolution theory By SETH BORENSTEIN, AP Science Writer
Thu Aug 9, 10:33 AM ET

WASHINGTON - Surprising research based on two African fossils suggests our family tree is more like a wayward bush with stubby branches, challenging what had been common thinking on how early humans evolved.

The discovery by Meave Leakey, a member of a famous family of paleontologists, shows that two species of early human ancestors lived at the same time in Kenya. That pokes holes in the chief theory of man's early evolution ? that one of those species evolved from the other.

And it further discredits that iconic illustration of human evolution that begins with a knuckle-dragging ape and ends with a briefcase-carrying man.

The old theory is that the first and oldest species in our family tree, Homo habilis, evolved into Homo erectus, which then became human, Homo sapiens. But Leakey's find suggests 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. She and her research colleagues report the discovery in a paper published in Thursday's journal Nature.

The paper is based on fossilized bones found in 2000. The complete skull of Homo erectus was found within walking distance of an upper jaw of Homo habilis, and both dated from the same general time period. That makes it unlikely that Homo erectus evolved from Homo 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, each having its own "ecological niche," Spoor said. Homo habilis was likely more vegetarian while Homo erectus ate some meat, he said. Like chimps and apes, "they'd just avoid each other, they don't feel comfortable in each other's company," he said.

There remains 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, is just too simple and keeps getting revised, 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 part of the Leakey team.

"The more we know, the more complex the story gets," he said. Scientists used to think Homo sapiens evolved from Neanderthals, he said. But now we 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.

Susan Anton, a New York University anthropologist and co-author of the Leakey work, said she expects anti-evolution proponents to seize on the new research, but said it would be a mistake to try to use the new work to show flaws in evolution theory.

"This is not questioning the idea at all of evolution; it is refining some of the specific points," Anton said. "This is a great example of what science does and religion doesn't do. It's a continous self-testing process."

For the past few years there has been growing doubt and debate about whether Homo habilis evolved into Homo erectus. One of the major proponents of the more linear, or ladder-like evolution that this evidence weakens, called Leakey's findings important, but he wasn't ready to concede defeat.

Dr. Bernard Wood, a surgeon-turned-professor of human origins at George Washington University, said in an e-mail Wednesday that "this is only a skirmish in the protracted 'war' between the people who like a bushy interpretation and those who like a more ladder-like interpretation of early human evolution."

Leakey's team spent seven years analyzing the fossils before announcing it was time to redraw the family tree ? and rethink other ideas about human evolutionary history. That's especially true of most immediate ancestor, Homo erectus.

Because the Homo 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 malformation or genetic mutations, Spoor said. The scientists also know it isn't Homo 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 Anton. 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. Primates 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 Homo erectus reproduced with multiple partners.

The Homo 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 Homo erectus and Homo habilis lived at the same time.

[Kortoso]

Great reporting as always, Ironhand. One quibble, of course:

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

Of course, chimps are apes. It's probably a mistake of the reporter's; they probably meant monkeys and apes.

Then again, don't chimps eat monkeys when given a chance?

[deuce]

Great reporting as always, Ironhand. One quibble, of course:

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

Of course, chimps are apes. It's probably a mistake of the reporter's; they probably meant monkeys and apes.

Then again, don't chimps eat monkeys when given a chance?

Hey Kortoso! Cool post, Ironhand. Yeah, chimps love meat, they just don't get many chances to eat it. So much for the idea that homo sapiens was "meant" to be strictly vegetarian.

I didn't think the article described "dimorphism" very well (or even mention the word). They seemed unaware that humans are still dimorphic, at least to a degree.

[Ironhand]

Perhaps the article meant chimps and gorillas; they are quite closely related.

Chimps eat baby baboons. Chimps have a strange relationship with baboons. Young chimps play with young baboons; not abusively, but as pets or playmates. Then, when a young baboon gets used to hanging out with the young chimps, some adult chimp captures the young baboon and eats it. The young chimps get very upset, but then they grow up and eat baby baboons themselves. I read a report that an old adult male baboon, who had been displaced from the leadership of his band by younger males, started hanging out with some young chimps, and they fawned on him and groomed him. He was probably too experienced and alert to let the adult chimps near him; in any case, an adult male baboon would be no easy kill for chimps.

Edited by Ironhand, 10 August 2007 - 10:54 PM.

[Kortoso]

Perhaps the same way a troop of Bigfoot would treat one of us?

[Ironhand]

WUSTL anthropologist studies earliest known human ancestors in Eurasia

By Neil Schoenherr

The first human ancestors to inhabit Eurasia were more primitive than previously thought, a WUSTL anthropologist has learned.

A team of researchers, including Herman Pontzer, Ph.D., assistant professor of anthropology in Arts & Sciences, has made the finding through analysis of hominin fossils in Dmanisi, Georgia.

The remains recently were discovered in the former Soviet republic and are the earliest known hominid fossils outside of Africa. The fossils, dated to 1.8 million years old, show some modern aspects of lower limb morphology ? long legs and an arched foot ? but retain some primitive aspects of morphology in the shoulder and foot. The species had a small stature and brain size more similar to earlier species found in Africa.

"Thus, the earliest known hominins to have lived outside Africa in temperate zones of Eurasia did not yet display the full set of derived skeletal features," the research concluded.

The findings, published Sept. 20 in the journal Nature, are a marked step in learning more about the first human ancestors to migrate from Africa.

The lead author of the paper is David Lordkipanidze, director of the National Museum of Georgia. Collaborators on the study include Pontzer and researchers from Georgia, Switzerland, Italy and Spain.

The new evidence shows how this species had the anatomical and behavioral capacity to be successful across a range of environments and expand out of Africa, said Pontzer. His area of expertise is how the musculoskeletal anatomy of an animal reflects its performance, ecological niche and evolutionary history.

"This research tells us that the limb proportions and behavioral flexibility that allowed this species to expand out of Africa were there at least 1.8 million years ago," Pontzer said.

Dmanisi is the site of a medieval village located about 53 miles southwest of Tbilisi, Georgia, on a promontory at the confluence of the Mashavera and Phinezauri rivers.

Archaeological exploration of the ruins began in the 1930s, but systematic excavations were not undertaken until the '80s. Pontzer has been studying the site for more than six years.

Edited by Ironhand, 02 October 2007 - 03:47 AM.

[Kortoso]

...not really Neanderthal... or is it?

Jane Goodall on the existence of Sasquatch

[Ironhand]

No, I don't think they're Neanderthals, I imagine, in the absence of more info, that they're something in between Austrolopithecus and Homo erectus. But I've been using this thread for all sorts of stuff about ancestral homonids, sort of a unifying theme. After all the title also refers to ogres and apemen. For a while, I couldn't relocate the thread, not realizing it had been moved from The Hyborian Age forum to General Discussions.

I think it's interesting that they differ from modern humans below the neck. I had the impression that most of the evolution that's taken place since Australopithecus has been above the neck.

Edited by Ironhand, 03 October 2007 - 04:25 AM.