Feet hold the key to human hand evolution [ make sure your fire insurance is up to date ]

BBC News ^ | Monday, January 18, 2010 | Victoria Gill

[SunkenCiv]

Scientists may have solved the mystery of how human hands became nimble enough to make and manipulate stone tools. The team reports in the journal Evolution that changes in our hands and fingers were a side-effect of changes in the shape of our feet. This, they say, shows that the capacity to stand and walk on two feet is intrinsically linked to the emergence of stone tool technology. The scientists used a mathematical model to simulate the changes. Other researchers, though, have questioned this approach. Campbell Rolian, a scientist from the University of Calgary in Canada who led the study, said: "This goes back to Darwin's The Descent of Man. [Charles Darwin] was among the first to consider the relationship between stone tool technology and bipedalism. His idea was that they were separate events and they happened sequentially - that bipedalism freed the hand to evolve for other purposes. What we showed was that the changes in the hand and foot are similar developments... and changes in one would have side-effects manifesting in the other." ...Robin Crompton, professor of anatomy at the UK's Liverpool University, said the study was very interesting but also raised some questions. "I am not personally convinced that the foot and hand of chimpanzees are a good model [of human ancestors' hands and feet] - the foot of the lowland gorilla may be more interesting in this respect," he told BBC News. He pointed out that there was a lot more to the functional shape and biomechanics of the human foot than just its proportions.

[wildbill]

I believe our forebears used their hands only for traveling through the boughs of the jungle.

On the other foot, they had opposable toes and made and used tools with their feet.

Over time, these abilities were reversed by evolution as hominids moved out of the trees and onto the plains. Unfortunately Walking on their hands put their heads below the level of the high grasses and those who refused to evolve became easy prey for quadriped predators.

The absolute proof of this is that this ability/trait is still visible in some unfortunate folks who have lost the use of their arms/hands and are still able to type out the complete works of Shakespeare using only their toes.

[SunkenCiv]

I guess the wild part is apropos after all. ;’)

[Ken H]

Our ancestors walked through the jungles tearing limbs off of trees...

[alstewartfan]

Before or after the hands were fully formed? And what happened to our super ape strength? I smell bull manure! Bob