Oldest DNA Ever
Paints Paleo-Picture

Sediment deposits from Siberia yielded 300,000- to 400,000-year-old DNA samples—the oldest authenticated ancient DNA to date—according to a new study in the 18 April 2003 issue of Science that suggests that scientists can use this source of DNA to paint more accurate pictures of paleoenvironments.

In addition to this record-breaking plant DNA, Eske Willerslev and colleagues extracted the DNA of Siberian vertebrates including woolly mammoth, reindeer, and musk ox from more recent sediment cores. The researchers conducted a temperate component of this study in New Zealand that retrieved DNA from several extinct birds and 29 plant taxa characteristic of the pre-human environment. This technique opens the door for extensive reconstructions of past ecological communities in areas where no macrofossils such as the hard and soft tissue remains of plants and animals are available.

The potential implications of these findings for the fields of paleontology, archaeology and ecology are vast, according to the authors. “Sedimentary DNA provides a unique opportunity to assess the accuracy of pollen-based paleoenvironmental records,” write the authors, who note that the high volume of waste products produced by large herbivores probably explains why the DNA sequences from these bulky vegetarians dominate the sediment samples.

—Daniel Kane

17 April 2003