Evolution: more genomic evidence of pre-planning Part One (Evolution)

by David Turell , Thursday, April 08, 2021, 23:50 (1323 days ago) @ David Turell

Another view of the early homo brain study with nice illustrations:

https://phys.org/news/2021-04-modern-human-brain-africa-million.html

An international team led by Christoph Zollikofer and Marcia Ponce de León from the Department of Anthropology at the University of Zurich (UZH) has now succeeded in answering these questions. "Our analyses suggest that modern human brain structures emerged only 1.5 to 1.7 million years ago in African Homo populations," Zollikofer says. The researchers used computed tomography to examine the skulls of Homo fossils that lived in Africa and Asia 1 to 2 million years ago. They then compared the fossil data with reference data from great apes and humans.

Apart from the size, the human brain differs from that of the great apes particularly in the location and organization of individual brain regions. "The features typical to humans are primarily those regions in the frontal lobe that are responsible for planning and executing complex patterns of thought and action, and ultimately also for language," notes first author Marcia Ponce de León. Since these areas are significantly larger in the human brain, the adjacent brain regions shifted further back.

The first Homo populations outside Africa—in Dmanisi in what is now Georgia—had brains that were just as primitive as their African relatives. It follows, therefore, that the brains of early humans did not become particularly large or particularly modern until around 1.7 million years ago. However, these early humans were quite capable of making numerous tools, adapting to the new environmental conditions of Eurasia, developing animal food sources, and caring for group members in need of help.

During this period, the cultures in Africa became more complex and diverse, as evidenced by the discovery of various types of stone tools. The researchers think that biological and cultural evolution are probably interdependent. "It is likely that the earliest forms of human language also developed during this period," says anthropologist Ponce de León. Fossils found on Java provide evidence that the new populations were extremely successful: Shortly after their first appearance in Africa, they had already spread to Southeast Asia.
(my bold)

Comment: adds no new facts but is a clear discussion. Larger brain capacity brings new artifacts as in the bold