The Black Koalas [TBKAU]

The word koala comes from the Dharug gula. Although the vowel 'u' was originally written in the English orthography as "oo" (in spellings such as coola or koolah), it was changed to "oa", possibly in error. The word is mistakenly said to mean "doesn't drink".[4] Because of the koala's resemblance to a bear, it was often miscalled the koala bear, particularly by early settlers.[5] Other names like monkey bear, native bear, and tree-bear have also been used.[4] Indigenous names include cullawine, koolawong, colah, karbor, colo, coolbun, boorabee, burroor, bangaroo, pucawan, banjorah, and burrenbong; many of these mean "no drink".[6] The generic name, Phascolarctos, is derived from the Greek words phaskolos "pouch" and arktos "bear". The specific name, cinereus, is Latin for "ash coloured".[7]

Koalas are asocial animals and spend just 15 minutes a day on social behaviours. In Victoria, home ranges are small and have extensive overlap, while in central Queensland they are larger and overlap less.[63] Koala society appears to consist of "residents" and "transients", the former being mostly adult females and the latter males. Resident males appear to be territorial and dominate others with their larger body size.[64] Alpha males tend to establish their territories close to breeding females, while younger males are subordinate until they mature and reach full size.[65] Adult males occasionally venture outside their home ranges; when they do so, dominant ones retain their status.[63] When a male enters a new tree, he marks it by rubbing his chest gland against the trunk or a branch; males have occasionally been observed to dribble urine on the trunk. This scent-marking behaviour probably serves as communication, and individuals are known to sniff the base of a tree before climbing.[66] Scent marking is common during aggressive encounters.[67] Chest gland secretions are complex chemical mixtures—about 40 compounds were identified in one analysis—that vary in composition and concentration with the season and the age of the individual.[68]