Thursday, August 04, 2005

Synthesis of Human Origins

kw: anthropology, paleontology, palaeontology, book reviews

Prior to about 1958, there was occasional talk about various "missing links," particularly once the "Piltdown Man" hoax was uncovered (1953). At the time, as a youngster, I was what I call a "general believer" in my faith, someone who accepted what I'd been taught, including a rather sketchy account of the creation, without much thought.

I do recall at an age before ten (we were attending a Congregational church) the pastor telling us that Genesis begins with two verses that skip over a vast period of time. Later, once I began taking my faith seriously, my studies led me to conclusions similar to those of G.H. Pember in Earth's Earliest Ages, that there is room for geologic ages of time in that "gap" (yes, I subscribe to the "gap theory"), and that specific wording in Isaiah, Job, and the Psalms requires assigning the "creation" in Genesis 1 and 2 to a relatively recent restoration after a destructive spiritual war in an older creation. I do not think I have it all exactly right, but I am certain that today's Intelligent Design Creationists have nearly everything wrong.

Pember disdained Darwin's hypotheses, but I do not. I greatly enjoy reading of progress in any science, including the study of human origins. I am a fan of Darwin, S.J. Gould, and others in between who promote evolutionary processes as the best explanation we have of the origin of the physical biosphere. The science says nothing of spiritual things—nor should it, and no text in the Hebrew-Christian Bible purports to be a geological or biological textbook—nor should it. Scripture is about divine-human relationships.

Thus I very much enjoyed reading The Complete World of Human Evolution by Chris Stringer and Peter Andrews. The title to me is tongue in cheek: today's complete is tomorrow's woefully inadequate. From the ad Thames & Hudson put in the back cover, they have a line of "The Complete..." books. Such hubris.

Back to missing links. Much more is heard of this matter today, even though quite a number of links have been found. Of course, no modern creationist will ever admit that any of the fossil species assigned to the genus Homo or the probable ancestor genus Australopithecus is a human ancestor anyway. But no matter what "link" may be found, they demand another between, saying the evidence is still too incomplete...and so on. Be that as it may, let those of us who give a bit of credence to the evidence of our senses continue the discussion.

Drs. Stringer and Andrews have compiled a tour de force, and they present it in a very readable fashion. I initially expected a rather long read, but there are few pages with more than 40% devoted to text. There are just too many things that need illustrating, and the authors have gathered the cream of the illustrators' crop.

The key concept in understanding paleontological discoveries is that there is no "great chain of being," leading inevitably to a supreme species. A joke I like shows a shrew, a monkey, an ape, a cave man, and a suited "salaryman" on successive steps. A lot of empty steps lead beyond, and the cave man says, "I wondered when you'd notice that there are a lot more steps." The better metaphor is a bush, a very bushy bush, with comparatively few living twigs, and the fossil record represented by the occasional bit of twig or branch; the great majority of the mass being beyond reach.

Thus, though a diagram early in the book shows about forty fossil species (and one living species, us!), the authors make clear that if the fossil record were truly comprehensive, there would likely be thousands of species. Considering that primate species seem to change into one or more daughter species as many as five times per million years, and that pre-ape-to-apes-plus-man history covers about twenty million years, the lineal ancestry of each living species (there are five, humans and four other apes) includes perhaps fifty species. In addition, there are a number of side branches that died out entirely, some after persisting for several million years, and most species in a genus had several sibling species.

Well, I could go on and on, but I'll briefly state that the book's contents are organized around introductory concepts & examples, discussions of the fossils, and interpretation. The illustrations, photos of fossils, maps, paintings of possible scenes, charts, and all are copious and well captioned. I particularly noted that the authors show species that lived later than about a million years ago as relatively hairless, as we are; and earlier species having perhaps less body hair than a gorilla, but a definite pelt nonetheless. I have long thought that the species that discovered fire was the first nearly hairless species. A combustible pelt is simply incompatible with the use of fire.

A lovely book, from which we can learn much.

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