Closest Human Ancestor May Rewrite Steps in Our Evolution

[CuriousFeeling]

http://news.yahoo.com/closest-human-ancestor-may-rewrite-steps-evolution-141606435.html

Quite fascinating article here. Remains of two organisms that are both hominid and hominin species. Scientists found that the brains of this species closely resembled ours, a more developed prefrontal and frontal lobe. Also, a female of the species they found had wider hips that its ancestors to accommodate offspring with larger brain sizes.

This could rewrite steps in human evolution.

 

[Aquarelle]

Wow! Super interesting!

 

[93JC]

There was an interesting article in National Geographic Magazine last month: http://ngm.nationalgeographic.com/2011/08/malapa-fossils/fischman-text

Where the discovery of Australopithecus sediba rewrites the steps in our evolution, something the Yahoo article barely speaks of, is that the prevailing anthropological opinion is that Homo erectus, our almost universally accepted predecessor from 0.5 to 2.0 MYA, was a descendent of Homo habilis. That connection was always a little murky though because H. habilis fossils (and some similar fossils often attributed to another species of hominin, H. rudolfensis) have been dated to about the same time as the oldest H. erectus. There has never been a concrete progression from one to the other because H. habilis fossils aren't older than H. erectus save one little jaw fragment found in Ethiopia, dated to about half a million years older than the oldest H. erectus fossils (~2.5 MYA vs 2 MYA).

These A. sediba fossils are older than most H. erectus and H. habilis fossils, but they are younger than the jaw fragment. So the new hypothesis is that H. erectus is a descendent of A. sediba and H. habilis was an offshoot that died out (like neanderthals).

This hypothesis isn't all that new though. There have been journal articles in the past that hypothesized habilis and erectus were two separate branches of evolution descended from A. africanus and/or A. garhi. Critics of Berger, the paleo-anthropologist who made the discovery, believe sediba isn't a separate species at all, rather it is another africanus specimen.


Still, it's pretty nifty.

 

[Octarine]

Interesting. Thanks for the summary 93JC.