Like other nocturnal creatures, these prosimians also have acute hearing with well developed external ears. Especially those which hunt, for they have to be able to detect the slightest movements of their prey in the darkness of the forest night. Their whiskers are also well developed. Prosimian reproductive anatomy also differs from those of anthropoid primates. For example, they have a different shaped uterus and a different type of placenta.
Many prosimians have at least four nipples and produce litters rather than a single offspring.
They have a different number of teeth, and the lower jaw is made up from 2 separate bones joined by cartilage. The two halves of the lower jaws are thus mobile, not fused together as in anthropoids. There are also differences in the digestive and blood circulation system. Prosimians even have their own toothbrush to go with it, in the form of a horny plate, on which there are tiny teeth, under the tongue, known as the sub-lingula . This is used for cleaning debris and accumulated bits of hair off the dental comb, which becomes lodged there during grooming.