The Science Fiction series at your fingertips – human evolution
|December 19, 2013||Posted by News under Human evolution, Intelligent Design, Naturalism|
Late last year, it was announced that the oldest assumed human sequence then published (400 kya) baffles experts because it belongs to an unknown group, one more like Denisovans (an extinct type of human) than Neanderthals. The DNA results from the “Pit of Bones” site in Spain were described as baffling (Nature), perplexing (BBC), hard to make sense of (The Scientist ), don’t quite know what to make of it (New Scientist), and creating new mysteries (New York Times) instead of neatly clarifying human evolution. October of that year had already brought the news that the human remains found at Dmanisi, Georgia, showed that many “separate species of human ancestors” never really existed and “may now have to be wiped from the textbooks.”
“Separate species” of human ancestors (that nonetheless interbreed)? There are many definitions of “species,” so the term can be flung around freely, if accompanied by suitable credentials.
One researcher in a discipline that tries to keep track of the general direction of findings (theoretical anthropogeny) recently found no consensus as to when the human race arose, after he offered colleagues a spread ranging from ~60,000 to ~500,000 years ago. In this context, it hardly seems worth mentioning that no known hominin (assumed human) is clearly an ancestor of both Neanderthals and current humans.
For all practical purposes, today’s humans are orphans, seeking our roots via scraps and artifacts, many of unknown authenticity or significance. If we are convinced that any discovery we make is better than uncertainty, we are in a suitable frame of mind to explore the questions. More.
The search for our earliest ancestors: signals in the noise
Now and then, a signal rises above the noise. From surprisingly early periods, we encounter special respect for the dead and a sense of the divine. Meanwhile, because we keep finding artifacts and organized activities from earlier periods than “expected,” the half human creature we were originally seeking continues to elude us. More.
Early human religion: A 747 built in the basement with an X-Acto knife
Whatever these unknown people saw or sensed, many consumed much of their lives celebrating and memorializing it. And yet curiously, instead of getting better at constructing temples, the Göbekli Tepe worshipers grew steadily worse:
The earliest rings are the biggest and most sophisticated, technically and artistically. As time went by, the pillars became smaller, simpler, and were mounted with less and less care. Finally the effort seems to have petered out altogether by 8200 B.C. Göbekli Tepe was all fall and no rise.
Was it a loss of faith? Whether or no, in the words of Göbekli Tepe’s discoverer Klaus Schmidt, “Twenty years ago everyone believed civilization was driven by ecological forces. I think what we are learning is that civilization is a product of the human mind.” More.
Human Origins: The War of Trivial Explanations
The overarching theory in biology has been, for over a century, Darwinian evolution: Natural selection acting on random mutation is the cause of all or most variation in life forms. As anyone who has monitored what the media says over the years will know, all evidence is either interpreted on its terms or ignored. Thus, humans are evolved primates, an unexceptional twig on the tree of life, though like other twigs, we are accidental outliers.
The obvious problems with all of these disunited and discordant theses can be summed up for convenience as: 1) If some aspect of chimpanzee behavior explains matters, why didn’t it produce the same result in chimpanzees? 2) If mere advantage (which every primate seeks) explains a development like the human mind, why did only humans experience it? More.
Why human evolution happened only once: the question no one has to answer
One recent walk on the wild side is worth noting just for what it shows about how little we really know — and how much we are willing to believe. Much publicity was given in 2013 to the idea that the differences between humans and chimpanzees arise from humans’ hybridization with pigs.
You think this is a joke? Well, yes, but in the current science press it isn’t. That is, “humans are probably the result of multiple generations of backcrossing to chimpanzees, which in nucleotide sequence data comparisons would effectively mask any contribution from pig.” This hypothesis, offered by geneticist and hybridization specialist Eugene McCarthy, incidentally reveals facts about human anatomy not usually offered as evidence by the proponents of the 98-percent-chimpanzee thesis, who don’t seem to be interested in defending themselves against the [pig thesis] More.
The Little Lady of Flores spoke from the grave. But said what, exactly?
The key fossil’s small brain was taken by many researchers as evidence that the Floresians must be a separate species. That and an odd-shaped wrist bone. But almost immediately, a competing narrative appeared. In November, leading Indonesian scientist Teuku Jacob (1929-2007) announced that the Flores hobbit was an “ordinary human” and “just like us,” but possibly with mental defects. Jacob took the bones to his own lab, and returned most of them the following February, amid charges that he had severely damaged them.
He also damaged the orthodox narrative. And Nature wasn’t having any of that “just like us” stuff. In March 2005, it triumphantly reported the results of a computer simulation that bolstered the new species claim, in a story titled “Critics silenced by scans of hobbit skull.” But the critics’ silence did not dispel lingering doubt about “Homo floresiensis.”
Concern was raised that the ongoing controversy might be good for creationism. One researcher offered that “we certainly make it easy for them when we have disagreements like this one. I think that a lot of what has been said is going to have to be retracted. Given the amount of media attention, it just makes the field look incompetent.” He concluded: “Nobody is on the side of the angels now.”
Not even the angels, it seemed. …
Neanderthal Man: The long-lost relative turns up again, this time with documents
Earlier we saw how much present-day evolutionary biologists needed and wanted to believe that we had found a new human species in Flores man a decade ago. But it quickly became clear that the ancient inhabitants of Flores were not appreciably different from other humans of their era, apart from very small stature.
The story was different back when Neanderthal skeletons, first unearthed in 1856, began to be studied. As Britannica puts it, “Using those skeletons as a basis, scholars reconstructed the Neanderthals as semi-human, lacking a full upright posture and being somewhat less intelligent than modern humans.” The story grew legs and was admirably suited to demonstrating the fashionable, then-new idea of Darwinian evolution. As a result, “Neanderthal!” is now a term of abuse. The man himself does not protest, of course, for his type is extinct.
Thus, until very recently, Neanderthal man has been explicitly treated as an extinct, separate human species — the status sought for Flores man — in so highly politicized an environment that classification likely depends not on the persuasiveness of facts but the power of factions. More.
A deep and abiding need for Neanderthals to be stupid. Why?
There has been a significant change in his status in recent years, as researchers began separating what we see from what we think ought to be or must be true. … In fact, quite apart from the fact that Neanderthals appear to have been part of our own families, they have persistently failed to be as stupid as Shermer’s account needs. Increasing numbers of finds are breaking down the supposed differences between them and other early humans. As one paleontologist puts it, “The historical downgrading of our Neanderthal cousins has gone well beyond the scientific.”
It’s not clear, however, that “the scientific” was driving the need to downgrade Neanderthal man so much as a Darwinian anthropology that is at odds with the archaeology. More.
What can we responsibly believe about human evolution?
Villa and colleague Wil Roebroeks carefully studied explanations for the extinction of the Neanderthals as a separate human group based on the assumption that they were inferior. Such hypotheses include the idea that they did not use complex, symbolic communication, were less efficient hunters, had inferior weapons, or were not omnivorous. As we have seen, none of these hypotheses panned out.
In any event, the current human genome incorporates Neanderthal genes; it’s at least possible that they were just assimilated, the way many tribes in millennia past were assimilated into larger groupings, empires, or nation states, and lost their separate identity. One question the new assessments raise is, was there ever more than one human race? More.
What questions about evolution come down to is, “Who ARE we?”
Commenting on a dispute over a supposed human ancestor, Smithsonian paleoanthropologist Richard Potts told the Wall Street Journal, “Evolution is wonderfully messy.” Few would dispute it, but a multitude of conflicting speculations does not add up to progress.
Maybe that is too challenging a way to put the question. How about, it comes down to what we can responsibly believe. More to the point, who are we?
One thing’s for sure: There is no reason, based on any of the above, to abandon a typical traditional religious or philosophical teaching on the origin, let alone the honor and dignity, of human beings. If anything, the sheer vacuity of claims made on behalf of “modern science” (not, in this case, to be confused with actual science) suggests the opposite. More.
– O’Leary for News