Monkeys are intelligent animals that can adapt to changes in their environment. This is why they are able to live in different parts of the world. However, they also have the ability to disrupt balance of ecosystems when introduced to new areas.
Most monkeys are highly social and live in groups called troops. These can range from a few individuals to thousands. Female monkeys usually stay with the troop where they were born, while males join new troops on reaching maturity. Occasionally, unattached adult males form harems with several females and their offspring.
These animals use facial expressions as well as vocalizations to communicate with other monkeys in their groups. They will stare down or away from a perceived threat to avoid fights and can also signal the mood of the group with their body posture. Monkeys will even change their body language to express a sense of fear or anger.
Many monkeys are omnivorous and will eat seeds, flowers, leaves, fruits, nuts, roots, bark, and even small insects including spiders. Some species are specialized in their diets; proboscis monkeys, for example, eat only ripe fruit while colobus monkeys have complex stomachs that allow them to digest toxic foliage.
Aside from eating, monkeys spend a lot of time playing. Young monkeys spend most of their waking hours learning the physical and social skills they need to become adults by engaging in play activities. For instance, Japanese macaques (also known as snow monkeys) will travel in troops to volcanic hot springs to soak in warm baths. It has been found that these thermal pools have a calming effect on the monkeys.