Most kangaroos hop. Tree kangaroos walk. Their back legs are shorter and stronger than a normal kangaroo's, with bendy ankles that let them climb up and down tree trunks. They are slow on the ground but very nimble in the branches, where they spend almost all their time.
They eat leaves, fruit and ferns. A tree kangaroo will sit on a high branch for hours, chewing slowly and snoozing in between. Their long tail isn't used for gripping like a monkey's - it's more like a thick scarf for balance, hanging straight down behind them.
PNG has more than ten different kinds of tree kangaroo. Some have golden coats, some are chestnut-brown, some are nearly black. Matschie's tree kangaroo, found in the Huon Peninsula, has a creamy belly and a rusty back and is one of the most famous. Many are shy, and some are very rare.
Communities in the Highlands have known tree kangaroos for thousands of years. Today, conservation projects work with local people to look after the forest, count the tree kangaroos, and help them stay safe. Some villages have created their own protected areas where the tree kangaroos cannot be hunted at all.