Tenrecs: Tenrecidae

Scientists have few details about many species of tenrecs, partly because the animals are relatively small and are typically only active at night. They rest during the daytime, often in tunnels that they construct. Some, like the Ruwenzori otter shrew, sleep on beds of grass in the tunnels. During their daily rest, several species are known to enter a state of deep sleep, called torpor, which allows them to conserve their energy. One species, known as the large-eared tenrec, is particularly tuned in to the outdoor temperature, and its internal body temperature quite closely matches the outdoor temperature. When weather becomes cool, its body temperature takes a similar dip, and the animal may enter torpor. In long, dry periods, some species take an extended deep sleep, called estivation (est-ih-VAY-shun), during which the heart rate and body temperature fall and the animal needs to burn far less energy to stay alive. Estivation may last days or even weeks. Tenrecs that estivate for longer periods will frequently plug the openings of their burrows in preparation for the extended sleep.

Adults likely spend most of their lives alone, coming together only for mating. Sometime, males will remain with the female while she's pregnant, a span that typically lasts about two months. A few reports suggest that some male-female pairs may remain together during other times of the year, too. Overall, scientists know little about mating rituals in most species, but they have observed some behaviors. In the hedgehog tenrec, for example, the females give off an odor during mating season that causes a milky substance to flow from glands near the eyes of males. Each year, females have one litter of one to thirty-two babies, depending on the species. The young, most of which are born blind and naked, apparently stay with the mother for at least four or five weeks, and possibly more.