Moles spend most of their lives underground in a system of permanent tunnels (2), the presence of which can be detected from above by molehills, by-products of the excavation process (2). They feed on soil invertebrates that fall into the tunnels (4). A favourite component of the diet is earthworms, which are often stored for later consumption after they have been immobilised by a bite to the head (4). This species of mole is typically solitary, and both sexes defend their territories vigorously (4). Males extend their tunnel systems during the short breeding season as they search for females (4); a single litter per year is the norm, averaging between 2 to 7 naked, blind young. The young are suckled for about a month and leave the nest at around 33 days of age (2), they then disperse above-ground; this period of the mole's life is the most fraught with danger, as they are extremely vulnerable to predators including owls, buzzards, stoats, dogs and cats (2). Female moles are the only mammals known to posses reproductive organs called 'ovotestes', which contain a normal functioning ovary as well as a testicular area that produces a large amount of testosterone. This intriguing feature may explain why female moles are as aggressive as males when defending their territories; it may also account for the external similarities between males and females (4).