Nicholas van Rijn rightly says:
"'We was animals long before we became thinkers...'" (p. 98)
On reflection, how could it have been otherwise? We are thinking animals, not thinking souls in animal bodies.
Van Rijn adds that, when forests receded, ground apes began to eat meat and to walk erect and developed hands to make weapons because they lacked claws or carnivores' teeth. I am told independently that the evidence indicates that bipedalism preceded opposable thumbs.
This contradicts a theory of human origins that I had read and accepted because it seemed plausible. It still does seem plausible although the evidence must come first. The theory: quadrupeds evaded predators by climbing into trees where they were free to chatter and developed opposable thumbs to grasp branches. When the forests receded, these quadrupeds-turned-bipeds walked in groups across the plains where their forelimbs grasped and manipulated parts of their environments while, in a social species, chattering became the physical basis of language. We recognize our earlier selves.
However, it seems that bipedalism preceded opposable thumbs and we need to know what did happen, not just which theory seems plausible.
7 comments:
Kaor, Paul!
I read the text of the 1859 edition of THE ORIGIN OF SPECIES. According to the editor of the Penguin Books version the original text is to be preferred over the later editions revised by Darwin, because he obscured his original theory with hesitations, changes of mind, and digressions.
Ad astra! Sean
Kaor, Paul!
The impression I got from what you quoted was that Old Nick agreed, it was bipedalism which allowed our remote predecessors to develop true hands.
Ad astra! Sean
Bipedalism made tool-use possible. It was not -prompted- by tool use. Chimps have hands, and occasionally strip twigs to get at termites, but they're not nearly as sensitive and precise as ours.
Kaor, Mr. Stirling!
That's my belief as well, a chimp's hands are simply not as efficient as ours.
Ad astra! Sean
Sean: well, they walk on their knuckles and their thumbs aren't fully opposable.
Note that our lineage diverged from that of chimps around 6 million years ago, but there were episodes of interbreeding well after that.
Kaor, Mr. Stirling!
I have noticed how differently chimps walk compared to humans.
That interbreeding of chimps with our lineage probably ceased about 2-3 million years ago.
Ad astra! Sean
Post a Comment