Are we humans simply remodelled apes? Chimps with a tweak? Is the difference between our genomes so minuscule it justifies the argument that our cognition and behaviour must also differ from chimps by barely a whisker? If “chimps are us” should we grant them human rights? Or is this one of the biggest fallacies in the study of evolution? NOT A CHIMP argues that these similarities have been grossly over-exaggerated - we should keep chimps at arm’s length. Are humans cognitively unique after all?
Monday, 20 April 2009
Could early humans climb trees?
The term "hominin" came into fashion a number of years ago to denote the "bipedal apes" - meaning extant humans and all human ancestors since the split from the common ancestor 6 million years ago - as opposed to any of the other great apes. When did our ancestors become truly bipedal, and did it mean that they had to sacrifice agility in tree-climbing in order to do so? Until recently, however, there were, apparently, no good biomechanical studies of chimpanzee limbs versus hominin limbs that could settle the matter. Now, Jeremy DeSilva has compared the detailed anatomy of talus (a bone in the lower ankle) and tibia (shinbone) between a number of chimpanzees and fossil early humans dating back to 4.12 million years ago. He finds that "chimpanzees engage in an extraordinary range of foot dorsiflexion and inversion during vertical climbing bouts" - far in advance of that which the early human ankle was capable. He concludes that, if early hominins could climb trees at all, they were doing it "in a manner decidedly unlike modern chimpanzees."
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