prosimian

mammal

Also known as: Prosimii

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July 13, 2026

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The term "prosimian" traditionally referred to a suborder of primates that included lemurs, lorises, and tarsiers. However, modern classification recognizes two suborders: Strepsirrhini (lemurs and lorises) and Haplorrhini (tarsiers, monkeys, apes, and humans). This revision occurred because tarsiers are more closely related to anthropoids (monkeys, apes, and humans) than to lemurs and lorises.123

Primates are mammals characterized by adaptations for arboreal life, including grasping hands and feet, stereoscopic vision, and a relatively large brain with a complex cerebral cortex. Their dentition is heterodont, featuring incisors, canines, and cheek teeth, with evolutionary trends showing a reduction in the number of teeth and an increase in molar cusps. The Eocene Epoch (56 to 33.9 million years ago) is significant for primate evolution, with fossils like Adapidae and Omomyidae providing insights into the ancestors of modern primates.456

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primate
Classification
…order Primates was divided into Prosimii (the primitive primates: lemurs, lorises, and tarsiers) and Anthropoidea (the bigger-brained monkeys and apes, including humans). It is now known that one of the “prosimians,” the tarsier, is actually more closely related to the “anthropoids,” so the classification of the primates has had to…
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…order Primates was divided into Prosimii (the primitive primates: lemurs, lorises, and tarsiers) and Anthropoidea (the bigger-brained monkeys and apes, including humans). It is now known that one of the “prosimians,” the tarsier, is actually more closely related to the “anthropoids,” so the classification of the primates has had to…
Read More