Abstract
The tiny (6-12 g) honey possum Tarsipes rostratus has many adaptations to harvest and digest the nectar and pollen that are its sole food items. It occurs only in southwestern Australia, primarily near nodes of high plant species richness in coastal sandplain heathlands. Honey possums are short-lived. Both sexes have an annual mortality rate of 86% and become sexually mature about 2-3 months after leaving the pouch while not yet fully grown. Most females carry pouch-young for almost all their subsequent life and males can sire young at all times of year. The small litter size (max. 4; mean 2.4) and slow growth of pouch-young is attributed to the nutritional constraints of their diet. Multiple paternity of litters indicates a polyandrous mating system. The honey possum is solitary and sedentary, males having larger home ranges (1 280 m2) than females (700 m2). It is both phylogenetically and ecologically distinct among mammals.