Unconventional use of a sorting technology could help palaeontologists to date lake sediments. This could enable better reconstruction of past environments and climates.

Pollen grains, which can be used in carbon dating, are often the only organic matter found in abundance in lake sediments. However, isolating the grains is difficult, often making their use in carbon-dating impractical. Richard Jones at the University of Exeter, UK, and his colleagues adapted a biomedical technique known as flow cytometry, which sorts labelled cells on the basis of how they fluoresce and scatter light. Pollen grains are naturally fluorescent, so could be separated from contaminants by size and shape.

In just four hours, the technique collected 2.75 million fossil grains — an amount large enough to date a sample.

J. Quart. Sci. 28, 229–236 (2013)