Some species, like the naked mole rat, also benefit from a form of group living.
A human head has about 100,000, while a naked mole rat has just 100.
The tunnel systems built by naked mole rats can stretch up to two or three miles in cumulative length.
The naked mole rats feel no pain when they are exposed to acid or capsaicin.
Coprophagia also has been observed in the naked mole rat.
Some mammals, such as naked mole rats and whales have lost some or all of their hair.
But this inactivation happens much faster in the naked mole rat.
The naked mole rats have eyes that don't see, but their noses and ears work well.
Life in the tunnel colonies of highly organised naked mole rats.
But among vertebrates, the naked mole rat is most like the social insects.
