Humans and our closest relatives the great apes have been sequenced, scientific model organisms such as fruit flies, mice, and dogs too. But why would anyone want to sequence the genome of Heterocephalus glaber (naked mole rats)?
You might not think it to look at these hideous looking fossorial rodents -- kind of like an old man's shriveled hairy prepuce with the teeth of Esther Rantzen (and not in the way the old man would agree to) -- but they are a well-spring of scientific intrigue.For a start, naked mole rats (from the Horn of Africa) and their larger furrier cousins Damaraland mole rats (from Namibia), are the only mammals to live live in societies like those of bees, ants, wasps, and termites with a single reproductive female and workers who do not breed but gather food to feed the queen and the pups (so called eusocial societies). Or rather than feeding the pups the tubers that the workers gather in their underground foraging, the workers feed the youngest with their own droppings -- the eating of droppings (or coprophagy) is not uncommon among rodents, rabbits do it, and another former animal of the week, the mountain beaver does it.
As well as being one of only two eusocial mammal species, naked mole rats are the longest lived rodents. They can live for up to 30 years -- a true rat of the same size would be lucky to live for three. Part of the reason for their longevity is likely their low metabolic rate, they don't regulate their own body temperature in the same way as most mammals, relying on the sheltered environment of their extensive tunnels and their hairlessness to do that for them, and in times of hardship when food and water are scarce they can lower their metabolisms even more -- perhaps a good thing for them right now given the situation in their home range.
A low metabolism is also likely an adaptation to the low oxygen environment of their underground homes. The high concentration of carbon dioxide in their tunnel networks would likely end up an irritant to many other animals as the gas would convert to acid, but luckily naked mole rats feel no pain: another fascinating facet of these animals. And then, their front teeth, which they use to dig burrow are on the outside of their lips, so they can gnaw away at the east African subsoil without getting mouthfuls of dirt.
But best of all, why their genes are of most interest to scientists, and another reason for their long lives: they do not get cancer. In decades of study not a single cancer death has been observed in the species -- the possession of two different cancer suppressor proteins (where most mammals have only one) helps prevent cancers. But other mechanisms may be involved in protection from cancer and longevity, and perhaps this genome sequencing will help lay bare the naked mole rats' secrets. Utterly ugly, utterly unlovely, but very very interesting.
