john hawks weblog

paleoanthropology, genetics and evolution

Enamelin gene loss in toothless mammals

Tue, 2009-09-15 08:30 -- John Hawks

Jerry Coyne describes a new paper on the accumulation of loss-of-function mutations to ENAM in lineages with tooth reductions: "Dead Genes for Tooth Enamel".

A new paper in PLoS Genetics continues the search for predicted dead genes — this time for genes that once made tooth enamel — and finds a lot of these wrecks. They’re exactly where you expect to find them — in toothless animals long thought to have descended from animals with teeth. So the “theory” of evolution is once again confirmed, although we hardly need further confirmation. But this paper goes beyond a mere redudant proof of common ancestry. The authors also make models of how the “enamel” genes degenerated, and, by calculating when this degeneration happened, predict what the teeth of common ancestors should look like. This prediction is in principle testable by finding the relevant fossils and looking at their teeth.

The post is detailed and potentially useful for classes.

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.