The past month has witnessed assorted claims that the origin of what makes us human has been at last unearthed, identified, or deduced. That none of them live up to the claim shows how maddeningly elusive that quest is.
The Ida business, for example, is something of a hoax. Ida is the nickname that paleontologist Jorn Hurum has given the beautifully preserved 47-million year-old fossil from Germany, which he and his team claim is the "missing link" between early primates and we humans. However, it's not an accident that if we saw a living Ida scampering across the driveway we would assume she was either a strange-looking cat or a lemur. Early primates branched into lemurs on one side and then on another side, evolved on a pathway that eventually sprouted monkeys, apes, and us. Hurum and company have published an article claiming that Ida (properly, Darwinius masillae) is an early sprout from that other side, thus developing after, and separately from, lemurs.
That would mean Ida was an early anthropoid--but experts aren't impressed by Hurum's claim, which is based mainly on Ida lacking two obscure features involving teeth and feet that lemurs have. Some think both lemurs and anthropoids branched of from Ida-type critters. Then there are issues as to where Ida might have fit in in terms of other sprouts from the anthropoid branch such as tarsiers and now-extinct creatures called omomyids.
The upshot is that Ida was one of a whole mess of lemurish critters of her moment, whose relationships to one another, and to the monkeys that would evolve later, are hotly contested and highly unclear at present. That she was an early version of a human in any sense is up in the air to say the least.
And even if it turns out that Ida was a very, very early anthropoid, the "missing link" idea is a tad Barnum and Bailey. Ida lived in the Eocene epoch; this was way, way back when mammals had just begun to rule the world after the extinction of the dinosaurs. Suffice it to say that this was the second of seven whole epochs within the post-dinosaurian Cenozoic Era. Ida, a skittering, lemurish little ick of a thing, is a missing link between early mammals and us in about the same sense as if Handel's work were newly discovered it could be advertised as the "missing link" between Gregorian chants and Li'l Wayne.
Ida was not anthropoid in remotely meaningful enough a way to merit all of this hype, such as a book and even a television special. I am reminded of America's last encounter with Hurum in another television documentary similarly overhyping the unearthing of the skeleton of a sea creature whose only real distinction from long-known discoveries was that it was, well, big. I suppose it's always good to see prehistoric mammals getting some play, given that they were as interesting as the dinosaurs but are rarely written about for adults. But still - science is being distorted here.
Then, Richard Wrangham's interesting book is now out, arguing that what distinguished us from our primate relatives was, of all things, cooking. The idea is that cooked food is more nutritious and easier to digest, which spurred brain development, and that meanwhile, sitting around fires sparked richer socialization habits.
This is one of the neatest of the many ideas currently circulating as to what made the difference between us and beasts that look oddly like us but can't talk and wind up in controversial cartoons. Yet in the end, Wrangham is describing not precisely us but Homo erectus, our predecessor from 2 million years ago. Derek Bickerton's is the deathlessly perfect line on Homo erectus, referring to ones in China who "sat for 0.3 million years in the drafty, smoky caves of Zhoukoudian, cooking bats over smoldering embers and waiting for the caves to fill up with their own garbage."
Humanoid, perhaps, but this was a long way from cave drawings, grammar and bosomy figurines.
On that, there was that figurine I mentioned in a previous post, heralded as demonstrating the birth of truly human mental sophistication but actually about fifty thousand years too late. Even among those, however, who understand that true humanity cannot have emerged in Mitteleuropa a few tens of thousands of years ago, attempts to figure out just why Homo became sapiens are frustratingly ill-starred.
It is typically supposed that language was a defining sapiens feature, and one can barely help rooting for a proposal that this marvelously complex and mysterious thing that is human language has its roots in mothers cooing and playing Pat-a-Cake with their infants as Dean Falk, Florida State University anthropologist and author of Finding Our Tongues: Mothers, Infants and the Origins of Language has proposed.
Falk's idea is that motherese, the high-pitched, slowly paced mode of speaking to infants centered on a few basic concepts such as family members, eating and (pick me) up, is why humans have language while primates have grunts and calls. Primate children can hold on to their mothers constantly, but human infants are born in such a primordial state that they cannot grasp well enough to hold on to their mothers and have to be carried, either in arms or in a sling.
Babies, however, thrive on physical contact, which Falk thinks meant a problem for early hominids: in order to forage, women had to put their infants temporarily aside. Motherese would have emerged as a way of soothing babies in face-to-face interaction, as a replacement for ongoing physical connection - and then evolved into language.
But what is the pathway from "Pookie see doggy-woggy?" to, say, Ida has been implausibly touted as a missing link? Or, do babies really tend to squall desperately whenever laid aside for even a few minutes? Falk writes according to a universe in which cribs and baby car seats would be impossible. Couldn't motherese be an offshoot of language rather than the other way around?
Mind you, the mere attempt at figuring out how we can talk, reason, and create deserves an A for effort--Falk seems closer to the mark for my money than other attempts such as Steven Mithen's notion that language started as singing, or Robin Dunbar's that it all started with grooming and gossip.
Yet in the end, explaining the emergence of consciousness--and why it happened only to us--is as challenging a question as explaining the origin of life. We can circle around it - Ida, Homo erectus, cooing at children to calm them down--but an empty space always remains.