June 28, 2011
http://crev.info/content/
If you care about the true history of the human race, don’t believe paleoanthropologists. They are clueless and confused. Every solution they come up with creates new problems, and their boastful announcements are likely to be overturned. That’s the gist of a commentary inPNAS by Bernard Wood,1 who wrote, “The origin of our own genus remains frustratingly unclear.” He ought to know; he’s an eminent paleoanthropologist himself.
For decades, paleoanthropologists have declared to the world that human beings originated in Africa and migrated out to colonize Europe and Asia. Prepare for a surprise. Dr. Wood said:
Although many of my colleagues are agreed regarding the “what” with respect to Homo, there is no consensus as to the “how” and “when” questions. Until relatively recently, most paleoanthropologists (including the writer) assumed Africa was the answer to the “where” question, but in a little more than a decade discoveries at two sites beyond Africa, one at Dmanisi in Georgia and the other at Liang Bua on the island of Flores, have called this assumption into question. The results of recent excavations at Dmanisi reported in PNAS, which suggest that hominins visited that site on several occasions between ca. 1.85 and ca. 1.77 Ma, together with recent reassessments of the affinities of Homo habilis, are further reasons for questioning the assumption that Homo originated in Africa.
Wood continued by showing how the Dmanisi specimens are hard to classify (along with Homo erectus), but if they are H. erectus, they appear contemporaneous with African specimens. Then there are the Liang Bua specimens dubbed Homo floresiensis, that seem primitive yet overlap substantially with modern humans (dated between 17,000 and 74,000 years old by evolutionary methods). These miniature humans remain bewildering to paleoanthropologists.
As for “where” questions, Wood showed that the evidence could support opposite views: that our ancestors migrated either out of Africa or into Africa. He offered “scenarios” but admitted, “it would be misleading to claim that any of the scenarios are supported by that meager evidence.” Then he moaned, “Another stumbling block for an ancestor-descendant relationship between H. habilis and H. erectus sensu stricto within Africa is that both the ancestor and the descendant overlap in time in East Africa for several hundred thousand years.” Ann Gibbons wrote about the debates surrounding H. habilis in Science,2 leaving it unclear whether it should be considered inside Homo or outside; “The problem is that there are precious few fossils of either H. habilis or H. rudolfensis, especially from the neck down.”
What is the lesson of this confusion? Wood hoped for more bones like those at Dmanisi, but ended with a worse admission of ignorance that extends beyond Homo erectus issues:
In the meantime we need to be realistic about what can, and what cannot, be deduced about hominin evolutionary history. It is sobering to realize that even in the case of a taxon such as Homo neanderthalensis that has an order of magnitude better fossil record than for early Homo, we still have much to learn about its origin and evolution.
That the problems are not merely the opinions of one paleoanthropologist can be seen by other recent early-man stories. Science Dailyechoed the confusion, stating on June 22,
Africa is regarded as the center of evolution of humans and their precursors. Yet long before modern humans left Africa some 125,000 years ago, their antecedents migrated from Africa to Eurasia many times, as is documented in the fossil record. How often, when and why hominoids went "out of Africa" is still a hotly debated field of intense research.
The article proceeded to describe a tooth from another “hominoid” that appears to have migrated into Swabia 17 million years ago, nearly ten times earlier than the conventional “out of Africa” hypothesis. To fit it into evolutionary timelines, they had to conclude that the line of this tooth was a dead end.
A BBC News article asked an obvious question, “Why is there only one human species?” All humans today are interfertile and clearly of one blood. Michael Mosley pondered, “Not so very long ago, we shared this planet with several other species of human, all of them clever, resourceful and excellent hunters, so why did only Homo sapiens survive?” Chris Stringer was quoted puzzling over the same question: “Even 100,000 years ago, we've still got several human species on Earth and that’s strange for us. We’re the only survivors of all of those great evolutionary experiments in how to be human.”
Those “evolutionary experiments” included Homo ergaster, who made tools, hunted skillfully, and “would have been a powerful runner, capable of speeds that would rival a modern Olympic athlete.” Moreover, this Homo was hairless and capable of dealing with heat like a modern beach bum. What’s the difference if “they’re very like us in terms of their overall body shape and body build”? And these were predecessors of Homo erectus in the evolutionary story.
Mosley was clearly just storytelling as he described groups of Homo responding to droughts and volcanoes, putting dates on events no paleoanthropologist ever witnessed. The only difference he could allege between the various Homo beings was brain size, a theory-laden measurement fraught with interpretation. Bigger is not always better (as with computers, comparing 1950 and 2010 models). Maybe smaller-brained individuals packed more power in less space. An article on PhysOrg about a Chinese scientist who measures skull capacities of Homo erectus fossils noted quite a bit of metrical diversity in brain size, “not unexpected given the temporal and geographical range of the species.”
Despite admitting that “Huge debates rage about human origins,” Mosley proceeded to write like an eyewitness reporter, presenting the standard out-of-Africa view as a “broad consensus among scientists” (contradicting Bernard Wood, and begging questions about how valid any consensus is among raging debaters). Sometimes, though, the questions are more interesting than the claims. Mosley quoted John Shea, professor of palaeoanthropology at Stony Brook University in New York, making a remark that casts doubt on the whole evolutionary story: “There's such a huge gulf between ourselves and our nearest primate relatives, gorillas, chimpanzees and bonobos,” he said, putting his faith in a big IF: “If that gap were populated by other hominids, we’d see that gap as not so much a gulf but rather a continuum with steps on the way.” Too bad all the species of Homo that Mosley discussed in his article appear just as equidistant from chimpanzees as the rest of us. If he had read Wood’s depressing commentary first, his claims might have been much less confident.
Now read Lund University’s press release on PhysOrg and see if the triumphant claim that “Cutting edge training developed the human brain 80,000 years ago” fits with what Bernard Wood said, besides begging questions about whether training developed the brain, or the brain developed training. The paleoanthropologists who inferred brain evolution from some spear points in an African cave failed to describe what mutation began a “period of transformation” that led to Homo sapiens, “man the wise”. Wise men learn to disbelieve scientists who, claiming to be wise, speak beyond the evidence.
1. Bernard Wood, Did early Homo migrate “out of ” or “in to” Africa?, PNAS, 2011 ; published ahead of print June 15, 2011, doi:10.1073/pn
http://crev.info/content/
If you care about the true history of the human race, don’t believe paleoanthropologists. They are clueless and confused. Every solution they come up with creates new problems, and their boastful announcements are likely to be overturned. That’s the gist of a commentary inPNAS by Bernard Wood,1 who wrote, “The origin of our own genus remains frustratingly unclear.” He ought to know; he’s an eminent paleoanthropologist himself.
For decades, paleoanthropologists have declared to the world that human beings originated in Africa and migrated out to colonize Europe and Asia. Prepare for a surprise. Dr. Wood said:
Although many of my colleagues are agreed regarding the “what” with respect to Homo, there is no consensus as to the “how” and “when” questions. Until relatively recently, most paleoanthropologists (including the writer) assumed Africa was the answer to the “where” question, but in a little more than a decade discoveries at two sites beyond Africa, one at Dmanisi in Georgia and the other at Liang Bua on the island of Flores, have called this assumption into question. The results of recent excavations at Dmanisi reported in PNAS, which suggest that hominins visited that site on several occasions between ca. 1.85 and ca. 1.77 Ma, together with recent reassessments of the affinities of Homo habilis, are further reasons for questioning the assumption that Homo originated in Africa.
Wood continued by showing how the Dmanisi specimens are hard to classify (along with Homo erectus), but if they are H. erectus, they appear contemporaneous with African specimens. Then there are the Liang Bua specimens dubbed Homo floresiensis, that seem primitive yet overlap substantially with modern humans (dated between 17,000 and 74,000 years old by evolutionary methods). These miniature humans remain bewildering to paleoanthropologists.
As for “where” questions, Wood showed that the evidence could support opposite views: that our ancestors migrated either out of Africa or into Africa. He offered “scenarios” but admitted, “it would be misleading to claim that any of the scenarios are supported by that meager evidence.” Then he moaned, “Another stumbling block for an ancestor-descendant relationship between H. habilis and H. erectus sensu stricto within Africa is that both the ancestor and the descendant overlap in time in East Africa for several hundred thousand years.” Ann Gibbons wrote about the debates surrounding H. habilis in Science,2 leaving it unclear whether it should be considered inside Homo or outside; “The problem is that there are precious few fossils of either H. habilis or H. rudolfensis, especially from the neck down.”
What is the lesson of this confusion? Wood hoped for more bones like those at Dmanisi, but ended with a worse admission of ignorance that extends beyond Homo erectus issues:
In the meantime we need to be realistic about what can, and what cannot, be deduced about hominin evolutionary history. It is sobering to realize that even in the case of a taxon such as Homo neanderthalensis that has an order of magnitude better fossil record than for early Homo, we still have much to learn about its origin and evolution.
That the problems are not merely the opinions of one paleoanthropologist can be seen by other recent early-man stories. Science Dailyechoed the confusion, stating on June 22,
Africa is regarded as the center of evolution of humans and their precursors. Yet long before modern humans left Africa some 125,000 years ago, their antecedents migrated from Africa to Eurasia many times, as is documented in the fossil record. How often, when and why hominoids went "out of Africa" is still a hotly debated field of intense research.
The article proceeded to describe a tooth from another “hominoid” that appears to have migrated into Swabia 17 million years ago, nearly ten times earlier than the conventional “out of Africa” hypothesis. To fit it into evolutionary timelines, they had to conclude that the line of this tooth was a dead end.
A BBC News article asked an obvious question, “Why is there only one human species?” All humans today are interfertile and clearly of one blood. Michael Mosley pondered, “Not so very long ago, we shared this planet with several other species of human, all of them clever, resourceful and excellent hunters, so why did only Homo sapiens survive?” Chris Stringer was quoted puzzling over the same question: “Even 100,000 years ago, we've still got several human species on Earth and that’s strange for us. We’re the only survivors of all of those great evolutionary experiments in how to be human.”
Those “evolutionary experiments” included Homo ergaster, who made tools, hunted skillfully, and “would have been a powerful runner, capable of speeds that would rival a modern Olympic athlete.” Moreover, this Homo was hairless and capable of dealing with heat like a modern beach bum. What’s the difference if “they’re very like us in terms of their overall body shape and body build”? And these were predecessors of Homo erectus in the evolutionary story.
Mosley was clearly just storytelling as he described groups of Homo responding to droughts and volcanoes, putting dates on events no paleoanthropologist ever witnessed. The only difference he could allege between the various Homo beings was brain size, a theory-laden measurement fraught with interpretation. Bigger is not always better (as with computers, comparing 1950 and 2010 models). Maybe smaller-brained individuals packed more power in less space. An article on PhysOrg about a Chinese scientist who measures skull capacities of Homo erectus fossils noted quite a bit of metrical diversity in brain size, “not unexpected given the temporal and geographical range of the species.”
Despite admitting that “Huge debates rage about human origins,” Mosley proceeded to write like an eyewitness reporter, presenting the standard out-of-Africa view as a “broad consensus among scientists” (contradicting Bernard Wood, and begging questions about how valid any consensus is among raging debaters). Sometimes, though, the questions are more interesting than the claims. Mosley quoted John Shea, professor of palaeoanthropology at Stony Brook University in New York, making a remark that casts doubt on the whole evolutionary story: “There's such a huge gulf between ourselves and our nearest primate relatives, gorillas, chimpanzees and bonobos,” he said, putting his faith in a big IF: “If that gap were populated by other hominids, we’d see that gap as not so much a gulf but rather a continuum with steps on the way.” Too bad all the species of Homo that Mosley discussed in his article appear just as equidistant from chimpanzees as the rest of us. If he had read Wood’s depressing commentary first, his claims might have been much less confident.
Now read Lund University’s press release on PhysOrg and see if the triumphant claim that “Cutting edge training developed the human brain 80,000 years ago” fits with what Bernard Wood said, besides begging questions about whether training developed the brain, or the brain developed training. The paleoanthropologists who inferred brain evolution from some spear points in an African cave failed to describe what mutation began a “period of transformation” that led to Homo sapiens, “man the wise”. Wise men learn to disbelieve scientists who, claiming to be wise, speak beyond the evidence.
1. Bernard Wood, Did early Homo migrate “out of ” or “in to” Africa?, PNAS, 2011 ; published ahead of print June 15, 2011, doi:10.1073/pn
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