Kangaroo the sniffing gains much information from smell cues. This behaviour enforces social cohesion without consequent aggression. During mutual sniffing, if one kangaroo is smaller, it will hold its body closer to the ground and its head will quiver, which serves as a possible form of submission. Greetings between males and females are common, with larger males being the most involved in meeting females. Most other non-antagonistic behaviour occurs between mothers and their young. Mother and young reinforce their bond though grooming. A mother will groom her young during or after it is suckling. A joey will nuzzle its mother's pouch
Doria's tree-kangaroo it a bear-like appearance. It is mostly solitary and nocturnal. Its diet consists of various leaves, buds, flowers and fruits. The gestation period is about 30 days, after which, the single young remains in the mother's pouch for up to 10 months. Doria's tree-kangaro is an IUCN Red List Vulnerable species. Its forest habitat is threatened by logging and forest clearance. Being large sized, it's also hunted for its meat. Doria's tree-kangaroo Doria's tree-kangaroo ("Dendrolagus dorianus") is a tree-kangaroo endemic to Papua New Guinea. This marsupial is found in montane forests of southeastern New Guinea island, at elevations between 600–3650m.