Monkeys are a group of primates in the suborder Haplorrhini (excluding the apes) that includes Old World monkeys and New World monkeys. They are very intelligent animals that can be trained to do all kinds of things. They can be naughty but they also have feelings like love, fear and compassion. They are often seen as tricksters but they are highly adaptable creatures that can live in a wide range of habitats, from desert-like savannas to snowy mountains.
Some monkeys have opposable thumbs, which help them hold food and tree branches. They also make a variety of sounds, such as purrs and screams, that can be heard from miles away. These vocalizations may be a way of communicating with other monkeys. For example, the call of a monkey screamed in pain when attacked by another monkey can alert other monkeys to the danger and encourage them to rescue it.
Many species of monkey live in close contact with humans, and some even cohabitate with them. They are found in a wide range of human activities and cultures, including agriculture, entertainment, and research.
Although monkeys are rarely used as pets, they play an important role in scientific research, particularly in advancing our understanding of the human brain and helping develop drugs and vaccines for diseases such as HIV/AIDS and malaria. Most of the monkeys that are used in research are macaques and marmosets. Their use is controversial, and there is much debate about how humane the treatment of these animals is. However, independent enquiries and expert panels have found that there is a strong case for the continued use of monkeys in research, subject to proper regulation.