Resumen de Prospecting for genetic gold
From muddy cliffs in Canada's Yukon territory, where miners flush out gold-laden gravel, Beth Shapiro is netting a different sort of treasure: DNA from thousands of mammoth, bison, horse, and other mammal bones. The goal of this evolutionary biologist from the University of California, Santa Cruz, is to paint a picture of the animal community here during the past 80,000 years. Mining has exposed fossils and layers of volcanic ash, which have been dated with radiometric methods, so Shapiro can pin down the ages of fossils back to before 40,000 years ago, the limit of radiocarbon dating. And thanks to the ever-shrinking cost of sequencing, Shapiro can analyze hundreds of individuals per species to learn about important genetic changes. The project's first papers are expected next year.
