Esqueleto de parente humano primitivo pode ter pele

quinta-feira, novembro 17, 2011

Skeleton of ancient human relative may yield skin

17:26 16 November 2011 by Catherine Brahic and Rowan Hooper

We're cleaning your teeth (Image: Natural History Museum)

As London's Natural History Museum takes delivery of two replica fossils, palaeontologists hint that they have discovered tools with the fossils, and mummified skin on the bones

It is strangely moving to hold it, knowing that this is an exact replica of a hand of one of our most ancient relatives. The bones looked frail and slight lying on the black felt, but fit snugly on my palm, knuckles lining up to knuckles (see photo). This woman, who died 1.9 million years ago after falling down a watering hole in what is now South Africa, had hands remarkably similar to mine.

This morning, the University of the Witwatersrand in Johannesburg, South Africa, gave a full cast of her fossil to the Natural History Museum in London, along with a cast of a child of the same species, Australopithecus sediba. Together, the two impressive fossils are calling into question the history of our species, and offering never-seen-before insights into how our very early ancestors lived.

At 1.977 million years old, the pair were nearly contemporary withHomo erectus, yet were discovered at the Malapa cave site in South Africa, far from the Great Rift Valley of Ethiopia, which hastraditionally been considered the cradle of humanity.
Mixed-up kid

The morphology of their bones – an odd mix of structures similar to ones seen in chimpanzees, australopithecines and even Homo erectus – backs up the notion that this is a transition species. Had some of the bones been found separately, says discovererLee Berger of the University of the Witwatersrand, it's likely they would have been ascribed to the different species ofAustralopithecus.

The fossils' hands and feet suggest that it could climb trees and yet was also bipedal. One possible explanation for these fossils' presence in South Africa, says Chris Stringer of the Natural History Museum, is that environmental changes drove several simultaneous changes in australopithecines across the continent. "It's possible that the environment was becoming drier and more open, encouraging changes like meat-eating and upright walking. What if we were doing this in parallel in different places?"

That could explain the emergence of several transition species at roughly the same time in different parts of Africa, including present-day Ethiopia and South Africa. Most of those species would have died out, leaving just one that evolved into modern humans.

Read more here: New Scientist