What is a thylacine's pouch used for?
Thylacines are extinct. Prior to their extinction, the young joeys crawled into the pouch to continue their development, having been born undeveloped like other marsupials. The joeys were then carried in the pouch until they were old enough to be left in a den.
Male Thylacines were unusual in that they, too, had a pouch. This was to protect their reproductive organs as they ran through the thick undergrowth.