A macaque troop is one of the most organised groups in the animal world. There are grandmothers, mothers, aunties, cousins, and lots of babies. Older monkeys teach younger ones how to find food, how to be safe, and where the best trees are.
Macaques are excellent at watching how something is done and then copying it. In some forests, scientists have watched macaques wash sandy food in the sea to clean it - a trick one monkey worked out, and then others copied. Macaques in Singapore know which fruit trees ripen first, which ponds have water in dry weather, and which paths take them through the park most quickly.
Their long tail is mostly for balance. Macaques can run along thin branches without slipping, leap from tree to tree, and even swim if they have to. Babies cling to their mum's belly fur and ride along while she climbs.
Singapore's parks share signs reminding people not to feed the macaques. A monkey that learns to expect food from people stops finding its own, and that isn't good for the monkey. The advice is: enjoy watching, then walk on.