News Release

Natural anti-freeze -- how arthropods survive the cold

Peer-Reviewed Publication

Society for Experimental Biology

<i>Onychiurus arcticus</i>

image: Upper panel shows Onychiurus arcticus. The effect of protective dehydration is shown in the lower panel. view more 

Credit: Raymond Borland

Given the choice, many of us would opt for warmer climes during the bleak midwinter. However, most of us cannot afford to move abroad for a few months, so instead we pile on extra layers of clothing to keep warm. Arthropods face much the same dilemma, as they cannot migrate long distances to avoid low winter temperatures – so why are they not killed off by the cold? Dr Melody Clark, from the British Antarctic Survey, will present data on the fascinating ways two species of these animals combat the cold on Tuesday 3rd April at the Society for Experimental Biology’s Annual Meeting in Glasgow.

Onychiurus arcticus (from the Arctic) uses protective dehydration to survive harsh Arctic winters. This means that water is lost from the body across a diffusion gradient between the animals’ super-cooled body fluids and ice in the surroundings. "During this process the body loses all its water and you end up with a normal looking head, and a body which looks like a crumpled up crisp packet when it is fully dehydrated. But add a drop of water and it all goes back to normal!" explains Dr Clark. Scientists examined the different stages of this process to see which genes were activated.

Cryptopygus antarcticus lives in the Antarctic and uses a different mechanism to survive cold temperatures. These creatures accumulate anti-freeze compounds which lower the temperature at which their bodies freeze, meaning they can withstand temperatures as low as minus 30°C. Within this population there is a clear divide into less- and more-cold hardened animals, which has been a puzzle to researchers. However, by looking for differences in gene expression levels between the two populations, scientists think that there could be a link to moulting (this is the process by which arthropods shed their exoskelton).

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  • This work will be presented as Poster A9.16 from 17:30-19:00 on Tuesday 3rd April.
  • Image © Dr Raymond Worland at the British Antarctic Survey – please give acknowledgement when using photo
  • British Antarctic Survey (BAS) is the UK’s national Antarctic operator, and has for the past 60 years been responsible for most of the UK’s scientific research in Antarctica. It is part of the Natural Environment Research Council (NERC).
  • Arthropods are the largest phylum of animals and include the insects, arachnids and crustaceans.
  • Exoskeleton is the anatomical feature that supports and protects an animal’s body.

Direct scientist contact
Contactable during the meeting via the SEB Press Officer.
Before meeting: E-mail: mscl@bas.ac.uk

This work will be presented on Tuesday 3rd April at the Society for Experimental Biology’s Annual Meeting (30th March – 4th April 2007) at the Scottish Exhibition and Conference Centre, Glasgow, UK.

Journalists are welcome to attend the meeting. For full details of the programme please visit: http://www.sebiology.org.uk/Meetings/pageview.asp?S=2&mid=&id=738


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