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Monkey

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Monkeys are members of the infraorder Simiiformes, also known as simians. This group includes a wide variety of primates with diverse lifestyles. In scientific terms, the classification can be complex. Some scientists use "monkey" to describe all simians, which includes apes. Other definitions exclude apes and only refer to non-hominoid simians. This distinction exists because apes are a sister group to certain monkeys.

Portrait of a father
Portrait of a father

This means they share a common ancestor but belong to different branches of the evolutionary tree.

To understand how these animals are related, we must look at their biological features. Monkeys and apes can be distinguished from other primates by specific traits. They typically have only two pectoral nipples. They also possess a pendulous penis and lack sensory whiskers. These physical markers help biologists group them together within the suborder Haplorhini. This suborder also includes tarsiers, which diverged from the simian line about 70 million years ago.

Simians are divided into two primary groups: Platyrrhini and Catarrhini. The Platyrrhini are the New World monkeys found in South and Central America. They emerged roughly 35 million years ago. It is believed they migrated to South America by crossing the ocean. Many New World monkeys have prehensile tails, which means they can use them to grasp branches. They also have varying types of color vision, ranging from trichromatic to monochromatic.

The Catarrhini are the Old World monkeys found in Africa and Asia. This group emerged about 25 million years ago. They include the superfamily Cercopithecoidea and the superfamily Hominoidea, which contains the apes. Unlike New World monkeys, Old World monkeys have non-prehensile tails or no visible tail at all. They also possess trichromatic color vision, similar to humans. Apes are considered part of this group because they are the sister group to the Cercopithecidae monkeys.

Please do not feed monkeys Koh Chang
Please do not feed monkeys Koh Chang

Our understanding of these animals has changed through historical discovery. In 1758, Linnaeus placed tarsiers and monkeys into a single genus called "Simia." Later, in the 18th century, Georges-Louis Leclerc, Comte de Buffon, realized the relationship between apes and monkeys. In 1812, Étienne Geoffroy established the name Catarrhini to group apes and Cercopithecidae monkeys together. These discoveries moved science away from seeing primates as a simple series of steps toward humans. Instead, modern cladistics focuses on monophyletic groups, which include all descendants of a common ancestor.

Monkeys exhibit an incredible range of physical sizes and behaviors. The pygmy marmoset is among the smallest, weighing just over two ounces. In contrast, a male mandrill can weigh up to 37 pounds. Most species are diurnal, meaning they are active during the day. While many are arboreal and live in trees, others like baboons live on the ground. Their diets are equally varied. They consume fruit, leaves, seeds, nuts, flowers, eggs, and even small animals like spiders.

Humans have a long and complex history with these primates. Monkeys are often used in scientific research due to their physical and psychological similarities to humans. Between 100,000 and 200,000 non-human primates are used in research globally each year. Some species have even participated in space exploration. For example, a rhesus macaque named Sam flew with NASA in 1959.

Monkey Sam Before The Flight On Little Joe 2
Monkey Sam Before The Flight On Little Joe 2

In the past, capuchin monkeys were trained as service animals to assist people with disabilities. However, current regulations and medical concerns have changed how these animals are used in society.

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🖼️ Images & Media (7)
File:Portrait of a father.jpg
Portrait of a father.jpg
File:Please do not feed monkeys Koh Chang.jpg
Please do not feed monkeys Koh Chang.jpg
File:"Monkey's food is Available here" store in Swyambhunath, Bagmati, Nepal.jpg
"Monkey's food is Available here" store...
File:Monkey Sam Before The Flight On Little Joe 2.jpg
Monkey Sam Before The Flight On Little Joe 2.jpg
File:Animals of Hindustan monkeys called bandar that can be taught to do tricks, from Illuminated manuscript Baburnama (Memoirs of Babur).jpg
Animals of Hindustan monkeys called...
File:Abhinandannath.jpg
Abhinandannath.jpg
File:Gabriel Cornelius von Max, 1840-1915, Monkeys as Judges of Art, 1889.jpg
Gabriel Cornelius von Max, 1840-1915,...
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