Temperature and Lifespan
Body temperature is demonstrated to affect life span in lower animals, and now that researchers are digging into how this works, some of the same longevity mechanisms already discovered in other studies are seen to be involved. Via EurekAlert!: "It's true that [nematode] worms don't regulate their body temperature, but they do regulate their response to high temperature, slowing down processes that would otherwise go much faster. In fact, they even use steroid hormones to do this, just as we do to regulate our temperature ... this might have been a very early evolutionary link between cold- and warm-blooded animals ... the authors suggest that at high temperature, the worm's thermosensory neurons produce a signal that stimulates expression of the daf-9 gene, which produces a steroid hormone that extends lifespan. The researchers propose that this thermosensory system allows C. elegans to reduce the effect that warm temperature would otherwise have on the processes that affect aging, which is something that warm-blooded animals do by controlling the temperature itself. This system may allow the animal to maintain a more normal rate of aging even if the temperature rises ... Previous research also has linked the rate of aging in mammals with temperature. If mice are tricked into thinking that they are in a hot climate, they lower their body temperature and live longer."
Link: http://www.eurekalert.org/pub_releases/2009-04/uoc--wcl041609.php