In “Stone Tools Influenced Hand Evolution in Human Ancestors, Anthropologists Say,” (ScienceDaily (Mar. 8, 2011), we learn (repeated twice more in a single short piece), that
New research from anthropologists at the University of Kent has confirmed Charles Darwin’s speculation that the evolution of unique features in the human hand was influenced by increased tool use in our ancestors.
The fact that Darwin speculated this adds greatly to the idea’s credibility, in a way that evidence wouldn’t.
Research over the last century has certainly confirmed the existence of a suite of features in the bones and musculature of the human hand and wrist associated with specific gripping and manipulatory capabilities that are different from those of other extant great apes. These features have fuelled suggestions that, at some point since humans split from the last common ancestor of living apes, the human hand evolved away from features adapted for locomotion toward alternative functions.
The release does not feature the routine searching question format of science stories: In this case, how do we know that it wasn’t the other way around? Wanting tools in the first place would promote the behaviour change of ceasing to walk on one’s hands. The fact that the hands are no longer weight-bearing might well simply mean that existing characteristics, previously suppressed, would flourish.
On tools and size of hands (which the authors tested): The Neanderthals have long been alleged to be too stupid to have as small, precise tools as homo sapiens of old, but when researchers actually produced Neanderthal model tools and tried them out,
Research by UK and American scientists has struck another blow to the theory that Neanderthals (Homo neanderthalensis) became extinct because they were less intelligent than our ancestors (Homo sapiens). The research team has shown that early stone tool technologies developed by our species, Homo sapiens, were no more efficient than those used by Neanderthals.
Put another way: Neanderthal tools were no less efficient than those of homo sapiens.
See also: Half an oaf is better than none?