As with all marsupials, koalas are born via the birth canal. They then crawl to the mother's backward-opening pouch by instinct, and lured by the smell of mothers' milk, where they stay for many months.
35 days after conception, the tiny, blind, hairless embryo emerges and moves into its mother's pouch, purely by instinct. At this stage it weighs about half a gram. Once in the mother's pouch, it...