Final answer:
Haplorhines are primates known for their dry noses, reliance on vision, diurnal activity, and inability to synthesize vitamin C. They are categorized into New World monkeys with rounded nostrils and often prehensile tails, while Old World monkeys and apes have narrow nostrils and no tails. Human evolution within the Haplorhini showcases increased brain size and bipedalism.
Step-by-step explanation:
The characteristics of Haplorhini, a suborder of primates that encompasses tarsiers, New World monkeys (Platyrrhini), Old World monkeys, and apes, including humans, can be described based on various distinctive features. The Haplorhini are divided further into two infraorders: Simiiformes (monkeys and apes) and Tarsiiformes (tarsiers). The Simiiformes are then split into Platyrrhini (New World monkeys) and Catarrhini (Old World monkeys and apes). New World monkeys (Platyrrhini) are found in Central and South America and have rounded, side-opening nostrils and often possess prehensile tails. On the other hand, the Catarrhini, hailing from Africa and Asia, feature narrow, downward-facing nostrils. The Catarrhini consists of Cercopithecoidea (cheek pouch and leaf-eating monkeys) and Hominoidea (apes and humans). A signature trait of the Cercopithecoidea is their bilophodont molars, whereas Hominoidea are characterized by the absence of tails and more terrestrial lifestyles. Humans, part of Hominoidea, have gone through numerous evolutionary stages, as indicated by characteristics such as increased brain size and bipedality. Moreover, Haplorhini primates have certain general traits that distinguish them from the Strepsirrhini primates or strepsirrhines. Haplorhines are usually diurnal and depend more on vision rather than smell, contrasting with the nocturnal, smell-oriented strepsirrhines. They also lack the ability to synthesize vitamin C and have greater reliance on dietary sources for this nutrient.