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paleoanthropology, genetics and evolution

Hard-headed science

Tue, 2011-04-12 08:11 -- John Hawks

Scicurious has been blogging from the Experimental Biology 2011 meeting. This morning she writes about some of Lynn Copes' work: "Experimental Biology Blogging: On Thick Skulls and...Chewing." Copes has kept a crew of mice on hard foods in a cold room, to get them to chew more. Would it give them thicker skulls?

Copes found that the mice who had the soft diet had weaker jaw muscles (masseters) than those eating normal chow or chewing more in the cold, but it wasn't by much, and the skull (cranial vault) thickness did not significantly vary in any of the conditions. While this may seem like negative data, this actually suggests that, rather than the activity varying skull thickness, the thickness of our skulls may be genetically determined. Copes hopes to eventually address this question by looking at the skulls of various modern and ancient human groups. By looking at the thickness of adult skulls compared to those of children, she hopes to determine whether skull thickness is genetically determined, and if so, when, and why, our skulls got so thin.

Another point in favor of Homo erectus as stone age pachycephalosaurs.

Neandertals

For years, I've worked on their bones. Now I'm working on their genes. Read more about the science studying these ancient people.

Denisova

From a finger bone of an ancient human came the record of a completely unexpected population. My lab is working on the science of the Denisova genome.

Acceleration

The advent of agriculture caused natural selection to speed up greatly in humans. We're uncovering some of the ways that populations have rapidly changed during the last 10,000 years.

Malapa

Just outside Johannesburg, the Malapa site is producing some of the most exciting finds in human evolution. This site is the headquarters of the Malapa Soft Tissue Project.