Female Hottentot golden moles use the size of male golden moles'
penises as a guide to their suitability as a mate, scientists
have discovered.  A long penis makes a male mole more attractive
and raises his chances of fathering offspring.  That suggests
that penis size is a sexually selected trait in this species.
Scientists have published details of the discovery in the
journal Mammalian Biology.  Golden moles are a group of small,
blind, highly specialised mammals endemic to sub-Saharan Africa.
They live underground in networks of specially dug tunnels,
feeding on earthworms and the larvae and grubs of invertebrates
such as insects.  "Golden moles are ideally suited to their
ecosystem, they are cylindrical in body shape, have a pointed
leathery nose shield that they use to push through the clay soil
and two modified forepaws that resemble picks," said Prof Nigel
Bennett of the University of Pretoria, South Africa, who
conducted the study with Ms Tarryn Retief and Dr Bill Bateman of
the same institution.