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Prosimii(Strepsirrhini):
The Strepsirrhini clade is one of the two suborders of primates. One of the most distinguishing characteristic of these 111 species is their wet noses, and it is this feature for which the grouping is named. The Greek name means having a curved or bent nose (a terpsimbrotos compound of strepho "bend" and rhis "nose"). Madagascar's only primates (apart from lemurs and humans) are strepsirrhines, although others can be found in southeast Asia. Strepsirrhines are considered to have more primitive features and adaptations than their haplorrhine ("dry-nose", in Greek "simple nose") cousins. Their moist nose is connected to the upper lip, which is connected to the gum, giving them a limit to the facial expressions they can manage. Their brain to body ratio tends to be smaller, indicating a lower intelligence. Their brain's olfactory lobes are larger, lending to the notion that they have a stronger reliance on smell. Their snouts are generally elongated giving them a dog-like appearance, although this is true of some monkeys, too. With the exception of the Aye-aye, all strepsirrhines have a dental comb—tightly clustered incisors and canine teeth—that is used for grooming. Another grooming adaptation is a claw on the second toe of all strepsirrhines, while the big toe is widely separated from the others allowing a vise-like grip for locomotion. About 75% of species are nocturnal and all have a shiny, reflective layer in the back of their eyes, although several diurnal species like the Ring-tailed Lemur have it as well. Many of the nocturnal species also have very sensitive hearing and ears they can move independently to capture sounds even better. Strepsirrhine reproduction differs greatly from haplorrhine reproduction. Instead of an individual cycle, strepsirrhines have a breeding season. They also have a litter of offspring and the females have a Y-shaped (bicornate) uterus and multiple sets of nipples.
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