Monday, August 2, 2010

Thoughts About A Missing Cousin

My original intention with this posting was to write a review of Clive Finlayson’s book entitled The Humans Who Went Extinct: Why Neanderthals Died Out and We Survived (2009), but it turned out to be too slim reed, as I will make clear at the end. So, this is something else, a mélange of thoughts about Neanderthals with a little piece of a review appended.

As I sketched out this piece, I realized that I’ve had a steady reading diet of things Neanderthal, frequently dipping into the flow of recent articles and books featuring or starring our close cousin from the human family tree. For many of us, Neanderthals (Homo neanderthalensis) hold a particular fascination which arises, I think, because they are such a powerful reminder that much of what we have considered quintessentially human is not unique to modern humans (Homo sapiens) (and quite possibly the very separation of these two human populations into separate species is misguided). Perhaps even more important, the emerging picture of the world of the Neanderthal tells us that the presence of modern humans in the here and how is largely a matter of chance. Given, say, a different roll of the climate dice, we would be among the missing human cousins. It’s a healthy counterweight to the belief that we are the culmination of the implementation of some plan.

Neanderthals exhibited behaviors we previously thought distinguished our species from others. The Smithsonian Institution’s Hall of Human Origins displays a Neanderthal youth’s skull showing clear evidence that, at a very young age, he experienced a severe blow to the head, damaging the left eye socket and area of the brain behind it. Movement on his right side would have been seriously compromised. But this didn’t condemn him to an immediate death. His people nurtured and cared for him over several years as evidenced by the withered right humerus (the right side of his body would have been controlled by the damaged portion of left brain hemisphere). I am struck by the implications of this. Sharing had to undergird the relationship he had with his group. Certainly, food and other resources were given to this possibly unproductive member of the group. Someone may have been spared to provide care, particularly when the child was first injured. It’s a wonderful fillip for seeing the Neanderthals in a different light.

We know Neanderthals buried their dead, testament to their cognitive and social attributes because burial rituals signal a belief in something more than the brutish present. Shinadar Cave in Iraq is a Neanderthal burial site dated at roughly 65,000 years ago. In What Does It Mean To Be Human? (2010), Richard Potts (director of the Smithsonian’s Human Origins Program) and Christopher Sloan describe one such burial:

. . . an adult male Neanderthal was carefully placed on his side in a shallow grave in a fetal position. There is good evidence that colorful flowers and evergreen boughs were intentionally placed in the burial with him. (p. 49)

The authors consider the import of this action, arguing that burial rituals

. . . reinforce social bonds and may have helped earlier human groups cope with life’s difficulties by allowing grieving. [Also], burials show that humans were able to conceive of something other than the immediacy and harsh realities of their daily lives.

Among those researchers most strongly staking out the position that Neanderthals’ capabilities and often their behavior differed little from ours is João Zilhão of the University of Bristol. As I understand it, in his eyes, the discovery of purported body ornaments (painted shells) at two Neanderthal sites puts a lie to the notion that modern behavior depends upon modern anatomy. Regardless of anatomical differences between Neanderthals and early moderns, the behavior of individuals in both populations was the same. (See, Symbolic use of marine shells and mineral pigments by Iberian Neandertals, PNAS, January 19, 2010.)  In a recent interview under the title “Did Neandertals Think Like Us?”, Zilhão asserted that the body ornaments show that, indeed, they did think like us. (Scientific American, June 2010). He explained the implications of his position:

There are several possible conclusions one could draw from this observation. Either modern cognition and modern behavior emerged independently in two different lineages, or they existed in the common ancestor of Neandertals and anatomically modern humans; or the groups we call Neandertals and modern humans were not different species and therefore we should not be surprised that despite the anatomical differences there are no cognitive differences, which is the conclusion I favor.

As for the role of chance, I’ll turn to Finlayson’s slim volume.  The Oxford-trained Finlayson certainly has the expertise to write on this subject. He is Director of the Gibraltar Museum and Director of Heritage for this British Territory, and has researched and written extensively on Neanderthals, particularly the last remnants of the Neanderthals who lived on Gibraltar between 28,000 and 24,000 years ago.

Though a handful of themes run prominently through the book, such as:  populations living on the environmental margins are the source of biological and cultural innovation, and modern humans are not intrinsically “better” than other ancient humans including Neanderthals, one theme trumps them all:  the presence today of modern humans, and the absence of Neanderthals (and other ancients) are the product of chance, driven largely by climate.

Consider just a few of the chapter headings in the book: Being in the Right Place at the Right Time; If Only . . . ; and Children of Chance (title of the epilogue). Finlayson places that the big uncontrollable – climate – in a starring role, creating the chances for Homo sapiens to arise, survive, and ultimately expand. Swings in climate are crucial for his explanation of the extinction of the Neanderthals. In one of his strongest statements, he asserts:

. . . human history has been an affair between contingency and luck, conspiring with the erratic whims of climate and geology to produce the improbable character that is Homo sapiens. (p. 105)

I devoted some time to reading this book because it held out such great promise, but, ultimately, it disappointed me. I can live with some repetition of central arguments, though I think Finlayson went too far. I suppose he was successful in that the reader comes away with an appreciation of the role of chance in human evolution, but this repeated note hurts the coherence of the book. There are other questionable choices about how he organized his material, but they aren’t the critical failure for me.

The most substantial problem with the book is that, despite its subtitle, it offers no detailed and nuanced portrait of Neanderthals. It fails to place them front and center, and so leaves the reader without a firm grasp of the where, when, and how of their emergence, endurance, and extinction. Oh, the information is there, spread throughout, but one struggles to accumulate it, given how fragmented it is. I think the problem lies in Finlayson’s decision to tell a broader story, the sweeping story of the rise and fall of innumerable proto-Ancestors and Ancestors (the terms he uses to identify those humans who ultimately yielded modern humans). Yes, that is the reality, the Neanderthals were just one among many failed human experiments, but that is not the story I thought he set out to tell and not the one I wanted to read. The expected main actor seems unfortunately marginal in this account.

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