Convoluted human evolution; relating jawbone and brain (Introduction)

by David Turell , Saturday, March 07, 2015, 15:36 (3550 days ago) @ David Turell

An ancient homo jaw bone dated at 2.8 million years ago, probably an early H. habilis, and it is the oldest homo fossil yet found near the vicinity where Lucy was discovered in the Afar valley.-> Moreover, LD 350-1 only dates to about 200,000 years after Lucy, and its primitive sloping chin resembles that of Australopithecus. However, the fossil's teeth and even proportions of its jaw suggest it belonged to the genus Homo rather than Australopithecus.
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> "'It's a mixture of more primitive traits from Australopithecus with quite a few traits only seen in later Homo," Villmoare said."-Now consider brain development, noted a day ago (March 06, 2015, 14:27)-"Thousands of genetic "dimmer" switches, regions of DNA known as regulatory elements, were turned up high during human evolution in the developing cerebral cortex, according to new research from the Yale School of Medicine."-Although the comments are about current human brains, note a 200,000 year jump from Australopithecus ( with approximately a chimp-sized brain, 400 cc)) to early habilis with larger brain (600 cc) requiring many, many genetic changes. And all by chance! No way!