Major features that define strepsirrhines and haplorrhines might be transmitted through a number of characteristics, including such as brain size, dental formula, nocturnal or diurnal vision, types of locomotion and many other.
Haplorrhines are defined as primates with larger brain size that leads to the longer term of development, longer lifetime and a higher lever of social interaction within the group. A dental formula has shown as the one with less number of premolars, that in its turn have a different form and presented with a Y5 pattern. Haplorrhines have a flat nose that followed by the loss of rhinarium. Haplorrhines have a color diurnal vision, good for day time activity. They are also defined as primates with sexual dimorphism. Among the other defining characteristics are the prehensile tail and protective bone …show more content…
A number of teeth are 36. They rely on a sense of smell, using rhinarium. They have nasal passages and large olfactory bulb in the front of the brain.
Strepsirrhines are more active at night time, with a very large eyes orbits and nocturnal vision as a preadaptation. Another trait is a combination of nails and claws, including toilet-claw on the second digit of feet. Smaller brain size affects the shorter term of development and lifetime.
Parvorders – platyrrhini (New World Monkeys) and cercopithecoidea (Old World Monkeys) are two that have a number of characteristics that distinguish them from one another. First that made scientist put them in different groups is the nose shape. Cercopithecoidea simply means that primates have hook-like nose form, with nostrils placed close to each other and pointed down. On the other hand, platyrrhini defined as primates with the flat nose, which nostrils are placed farther apart and pointed outward.
The dental formula for both parvorders also has distinctions. Old World Monkeys have a big, sharp canines that honed against the first lower