The deepest fears of male
humans Hottentot golden moles have been confirmed by a new study, which reveals that penis length is a significant factor when females select partners for sex.
Hottentot golden moles, native to sub-Saharan Africa, are polygamous and mate all year long.
Researchers found that males with long penises were more attractive to females and had higher chances of fathering offspring.
"Long" in the world of Hottentot moles is something of a relative term, however; penis size varies from 1.2 to 2.5mm. "They probably have one of the smaller penises per length of body in the animal kingdom," said Prof Nigel Bennett, part of the University of Pretoria team who produced the study.
The moles rarely venture overground and scientists believe their mating habits may be moulded by a cramped and dark ecosystem, which make it difficult for potential partners to measure each other up apart from through size and strength.
"Judging penis size when mating may be one of the only criteria they have available to them," said Dr Bill Bateman - adding that such judgements were unnecessary for humans since "we tend to have a whole lot of pre-copulatory mechanisms to choose mates".
In humans "penis size is something that is only discovered once a mate choice has already been made".
Fighting for the honour of most enlightening sexual habits in the natural world are the duck and the argonaut.
Despite their reputation for blandness, male ducks have corkscrew shaped genitalia that can extend to 17 inches long.
The ocean-dwelling argonaut octopus, aka paper nautilus, has a penis that can detach, find a mate, and return to its owner via the power of a tail. How about that?