Ho-Hum; Paleoanthropologists Confused Again

Upsets are so common in evolutionary studies of human ancestry, bystanders might well ask how often they find anything worth believing.

“Hominin DNA baffles experts” reads a headline on Nature News, one of a slurry of reports about the genome deciphered from the bone of an alleged human ancestor found in a Spanish cave.  The pieces of the puzzle of human evolution are not falling into place.  “Another ancient genome, another mystery,” the article sighs.

DNA gleaned from a 400,000-year-old femur from Spain has revealed an unexpected link between Europe’s hominin inhabitants of the time and a cryptic population, the Denisovans, who are known to have lived much more recently in southwestern Siberia.

European ancestors were supposed to be closer to Neanderthals than to the Denisovans.  Researchers are “baffled” by the new data.  Chris Stringer says it is “not what I would have expected.”  Svante Pääbo says “This really raises more questions than it answers.”  The article adds, “researchers interested in human evolution are scrambling to explain the surprising link, and everyone seems to have their own ideas.”  They want hope, but they offer befuddlement:

Clive Finlayson, an archaeologist at the Gibraltar Museum, calls the latest paper “sobering and refreshing”, and says that too many ideas about human evolution have been derived from limited samples and preconceived ideas. “The genetics, to me, don’t lie,” he adds.

Even Pääbo admits that he was befuddled by his team’s latest discovery. “My hope is, of course, eventually we will not bring turmoil but clarity to this world,” he says.

Other articles don’t add much clarity, either.  National Geographic, awfully quiet these days about their heroes of the 1980s, the Leakeys, says it “scrambles” the human origins picture.  Live Science spoke of a “mysterious branch of humanity.”  Science Now says Pääbo thought they’d find this kind of genome in China, not in Europe.  Another paleontologist says, “It is all much more complex than we thought.”  Various “experts” propose “scenarios” to answer the conundrum, “What was Denisovan DNA doing in a proto-Neandertal 7500 kilometers from Siberia?”  Or, as the BBC quipped, from Siberia to Iberia?  The story becomes lurid with various incompatible groups interbreeding but losing the DNA they gained.

The paper leaves some researchers frustrated. The authors “arrive at no conclusion,” grumbles paleoneurologist Emiliano Bruner of the Spanish National Research Center for Human Evolution in Burgos. “This is not a great advance, leaving all hypotheses still on.”

None of them, of course, leave the creation explanation still on, despite their frustration.  When all other hypotheses end in frustration, though, would it not be wise to think outside the box?  Judging their reactions, it appears they rather enjoy the frustration inside the box.  Ian Tattersall says curiouser-ly, “All I can say is, this gets mysteriouser and mysteriouser.”

Far out ape:  Meanwhile, on the ape end of the supposed continuum, there are puzzles about the “tree dwelling bipedal human ancestor” dubbed Orrorin.  Science Daily reported that it seems similar to ancient apes and “Lucy” but not to living apes.  (Check out Lucy’s new “svelte look” on Science Now, as if she’s on a fashion walk.)  Since there are other extinct apes, it’s not clear Orrorin was heading to meet Adam.  And so much for a continuum between chimpanzees and peopleL  “Living apes have long and independent evolutionary histories of their own, and their modern anatomies should not be assumed to represent the ancestral condition for our human lineage,” William Jungers of Stony Brook School of Medicine quipped.  PhysOrg says that this specimen (also called “Millennium Man”) turns out to be “less chimp-like than thought.”  He seems to be describing an evolutionary bush, not a tree.  What, then, can be deduced about human evolution from fossils?  How do they know these were not branches of apes that simply went extinct, and had nothing to do with human origins?

Cave shadows:  Given these anomalies, it’s hard to get excited about Live Science‘s picture gallery of the Siberian in Iberia, or Science Daily‘s speculations about when and why some animals get bigger brains in their genes, or PhysOrg‘s story about some lemurs that sleep in caves.  Don’t bats do that?  and centipedes?  Are we descended from them based on sleeping in caves?

Neo-Neanderthals:  Science Daily claimed, based on tooth analysis, that “No known hominin is ancestor of Neanderthals and modern humans,” yet evidence shows the two interbred (or “had sex with mystery relatives,” Live Science claims – maybe even the primitive Homo erectus!).   Does this not mean all three were members of the same species by definition?  National Geographic leaves the common ancestor another “mystery” that requires a “much earlier split” between their lineages.  “There may be an as-yet-unknown human hiding in the mix, and this human may be key to solving the puzzle of when our ancestors split from Neanderthals,” the article teases.  “Whether that species is waiting to be discovered in the field or is hiding within the broken and scattered remains of fossils already collected is a mystery waiting to be solved.” Isn’t science supposed to be dealing in observational facts?

Meanwhile, evidence continues to accumulate that Neanderthals were no dumb brutes clubbing each other. Live Science reports, “Tidy Cavemen: Neanderthals Organized Their Shelters.”  One wonders how that headline would have been received in Haeckel’s day on up through the 1960s.  It probably would have felt like a bonk on the head.

Yet scientists have the gall to tell us, as found on PhysOrg, that humans are not smarter than animals, just different.  Sure.  That’s why we all love to go to animal orchestras, read animal literature, and attend animal scientific conferences.  Dr. Arthur Saniotis from the University of Adelaide is out to debunk the “belief of human cognitive superiority” that “became entrenched in human philosophy and sciences” ever since Aristotle.

Actually, after listening to the paleoanthropologists, maybe Saniotis is onto something, at least for certain human subpopulations.  What does one expect from a flock of DODOs?