Terrawatch: midge fossils offer insight into past climates

A study of fossilised insects suggests a correlation between their body size and the temperature

Most of us want to run a mile when the midges arrive, but not so for Viktor Baranov, who whips out his microscope to measure the insects. As well as measuring modern midges, Baranov has been looking at fossilised midges, and found that their size can be used to understand the climate going back hundreds of millions of years ago.

Baranov, a palaeontologist at Ludwig Maximilians University in Munich, chose to measure the non-biting Diptera midge. It is already well known that warm-blooded animals become larger as the climate becomes colder - for example, polar bears are much bigger than bears living in the tropics - so Baranov and his colleagues decided to see if the so called Bergman rule" would hold for insects too.