Monkey Day

What the day is

Monkey Day is observed on December 14. It began in 2000, when an art student at Michigan State University wrote it on a friend's calendar as a joke, then marked it with fellow students. It spread through their artwork and comics and online, and is now used by primate conservation groups as a genuine awareness date.

Origin and background

The biology is where the day gets interesting, because the word monkey does not describe a real group.

Primates split into two broad monkey populations. Old World monkeys, in Africa and Asia, include baboons and macaques, and have downward-facing nostrils and no grasping tail. New World monkeys, in Central and South America, have sideways-facing nostrils, and a few of them have the prehensile tail that cartoons treat as standard equipment for all monkeys.

Here is the catch. Apes, which include gorillas, chimpanzees, orangutans, gibbons and humans, are more closely related to Old World monkeys than Old World monkeys are to New World ones. So any group containing all the monkeys and excluding the apes is not a branch of the family tree at all. Either monkey is an informal convenience, or apes are monkeys and so are we. Biologists differ on which correction they prefer.

Tarsiers and lemurs, often included in the day, sit further out again and are not monkeys under any reading.

The conservation situation is serious. A large share of primate species are threatened, driven by habitat clearance for agriculture, hunting, and capture for the pet trade. Primates are slow breeders, which makes recovery from population losses correspondingly slow.

How to take part

• Support a primate conservation organization working on habitat rather than on individual animals alone.
• Check products against a deforestation-free sourcing standard.
• Never share or reward video of primates kept as pets, which drives demand for capture.
• Learn to tell an ape from a monkey, starting with the tail.
• Visit a sanctuary rather than an attraction offering photographs with animals.