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Rating: 
Summary: It's an ill wind . . .
Review: In his innovative view of the course of human evolution, Stanley postulates that our species' ancestors essentially followed the course his mentor , Steve Gould proposed - a sudden appearance, followed by a long, stable period, then extinction. Using hominid fossils available at time of publication, he argues that "Lucy" - Australopithecus afarensis - represents a transition between tree-dwelling apes and ground-striding humans. He further contends she is a direct forebear of humans. What brought her and her kin to earth was the impact of global cooling instigated by the suture of North and South America through the Panamanian isthmus. This closure interrupted long-extant wind and ocean current patterns. A new, dry wind swept across Africa dehydrating the land and forests. With fewer trees, full-fledged ground dwelling offered a better option for survival.Stanley accepts the recent revisionist view of Lucy - that her bipedalism was more opportunistic than her diet and lifestyle dictated. Her long arms suggest a heavy investment in the arboreal environment. Toes appear better suited to climbing than walking. He dismisses the Laetoli footprints as an aberration, unrepresentative of typical daily life. Stanley sees her commuting between scattered woodland and open grassland. The retreat of the forest presented an opportunity for a new species to emerge - Homo erectus. Erectus, of course, was the great wanderer who moved out of East Africa, beginning the great human migration to Asia. With erectus came the move to long-term child care, especially compared to other primates. Large brains meant difficult births. If a child was to survive, it required nurturing. The brain itself, Stanley further suggests, evolved by demanding greater resources. Stanley's narrative is marred by incessant paeans to Stephen Gould's "evolution by jerks". Punctuated equilibrium has been essentially laid to rest as the fundamental mechanism of natural selection. It's not only disappointing to see Stanley flogging the concept with such ardour, but his reverse projection of the path of human evolution back through the history of life smacks of the worst kind of a priori reasoning. There simply isn't enough fossil evidence to warrant the direct link between Australopithecus and Homo sapiens. He spends an unreasonable amount of text arguing why bipedalism preceded large brains, with lengthy accounts of the physiology involved. This is old news, well covered in works by Johanson and others. Worse, it adds little to his thesis. While the basic theme is worth noting, Stanley could have covered the idea without wandering so far afield. A challenging but hardly definitive study. [stephen a. haines - Ottawa, Canada]
Rating: 
Summary: Great hypothesis but could have been shorter.
Review: Stanley obviously knows his stuff (and seems, at times, to be somewhat impressed with himself), but the book was too long for what he had to say. However, I did find his ideas interesting. I was especially intrigued by his assessment of the science of anthropology, and how it lags behind broader paleontological theory. Generally, the book was a good read, even though I felt compelled to skim some sections that seemed overly detailed.
Rating: 
Summary: Superb Book On The Emergence Of Homo Erectus
Review: This book proposes an interesting hypothesis for the emergence of Homo Erectus approximately two and an half million years BP coupled with an explanation for the concomitant disappearance of Australpithecus well documented by an array of compelling evidence. I found it riveting.
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