Haplorrhini

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Haplorrhini
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Family:	'

Haplorrhini is a suborder of primates that includes the tarsiers and the simians, which are further divided into the platyrrhines (New World monkeys) and the catarrhines (Old World monkeys and apes, including humans). The term "Haplorrhini" is derived from the Greek words "haplo" meaning "simple" and "rhin" meaning "nose," referring to the simple, dry noses of these primates, in contrast to the wet-nosed strepsirrhines.

Characteristics

Haplorrhines are distinguished by several key characteristics:

• Nasal Structure: Unlike strepsirrhines, haplorrhines have a dry nose and a simple nasal structure. This is due to the absence of a rhinarium, which is the moist, naked surface around the nostrils found in strepsirrhines.

• Vision: Haplorrhines generally have better vision than strepsirrhines, with a greater reliance on sight over smell. They have a more developed visual cortex and, in many species, color vision.

• Brain Size: They tend to have larger brains relative to body size compared to strepsirrhines, which is associated with more complex behaviors and social structures.

• Reproductive Traits: Haplorrhines typically have longer gestation periods and give birth to more developed young. They also have a more complex placenta compared to strepsirrhines.

Classification

The suborder Haplorrhini is divided into two infraorders:

• Tarsiiformes: This infraorder includes the family Tarsiidae, which consists of the tarsiers. Tarsiers are small, nocturnal primates found in Southeast Asia, known for their large eyes and unique ankle bones.

• Simiiformes: Also known as "simians," this infraorder is further divided into two parvorders:

 * Platyrrhini: Commonly referred to as New World monkeys, these primates are found in Central and South America. They are characterized by their broad, flat noses and prehensile tails in some species.
 * Catarrhini: This group includes Old World monkeys and apes, including humans. They are characterized by their narrow noses and downward-facing nostrils. Catarrhines are found in Africa and Asia.

Evolutionary History

Haplorrhines are believed to have diverged from strepsirrhines approximately 63 million years ago. The earliest haplorrhines were likely small, nocturnal, and insectivorous. Over time, they diversified into the wide array of species we see today, adapting to various ecological niches.

Conservation

Many haplorrhine species are threatened by habitat destruction, hunting, and the illegal pet trade. Conservation efforts are crucial to protect these primates, many of which play important roles in their ecosystems as seed dispersers and as part of the food web.

Also see

• Strepsirrhini
• Primate
• Evolution of primates
• Tarsier
• New World monkey
• Old World monkey
• Ape