Bats have already set themselves apart from other mammals as the only members of our class to have mastered flight (sorry flying squirrel, that gliding crap doesn't count). But the secret of flight has given bats some awesome perks.
Relative to their size, bats live remarkably long lives. Rodents of similar stature typically live only one or two years, but bats that survive their hazardous first year often can live for a good 20 years, with rare cases of bats reaching 30. And yet bats are notorious carriers of deadly viruses. "Carriers" is the key word there, because while they can often be the source of viral outbreaks in livestock, their own immune systems are supercharged, leaving them protected against most serious diseases.
Researchers at the Australian Animal Health Laboratory, a part of Australia's national science agency the Commonwealth Scientific and Industrial Research Organisation (CSIRO), teamed up with scientists at the Beijing Genome Institute to sequence a pair of bat genomes. The genomes came from the Australian mega bat, otherwise known rather wonderfully as the black flying fox, and the Chinese micro bat. The genomes were then compared to eight other mammalian species.
According to CSIRO researcher Dr. Chris Cowled, the bats' genomes suggest their strengthened immune response and consequent longevity actually come from their ability to fly:
Bats are a natural reservoir for several lethal viruses, such as Hendra, Ebola and SARS, but they often don't succumb to disease from these viruses. They're also the only mammal that can fly, and they live a long time compared to animals similar in size. Flying is a very energy intensive activity that produces toxic by-products but we can see that bats have some novel genes to deal with these toxins. We're proposing that the evolution of flight led to a sort of spill over effect, influencing not only the immune system, but also things like aging and cancer. They've been around since the time of the dinosaurs, at least 65 million years, and they're among the most abundant and widespread mammals on the earth."
Their research has just been published in Science.
Image by LOLren on Flickr.