Phascolarctos cinereus Skull Replica or Koala Male measures 6 inches. Koala Male Skull Replica is museum quality polyurethane cast. 2-part skull (separate cranium and jaw). Made in USA. Original California Academy of Sciences specimen.
The Phascolarctos cinereus or Koala is found in coastal areas of the mainland’s eastern and southern regions, inhabiting Queensland, New South Wales, Victoria, and South Australia.
It is the only extant representative of the family Phascolarctidae and its closest living relatives are Wombats.
The Phascolarctos cinereus or Koala is easily recognisable by its stout, tailless body and large head with round, fluffy ears and large, spoon-shaped nose. The Koala has a body length of 24 to 33 in. and weighs 9–33 lb. Their fur color ranges from silver grey to chocolate brown.
The Koalas typically inhabit open Eucalyptus woodland, as the leaves of these trees make up most of their diet. This eucalypt diet has low nutritional and caloric content and contains toxic compounds that deter most other mammals from feeding on it.
The Phascolarctos cinereus or Koala has several adaptations for its poor, toxic and fibrous diet.
The animal’s dentition consists of the incisors and cheek teeth (a single premolar and four molars on each jaw), which are separated by a large gap (a characteristic feature of herbivorous mammals).
The Koala bites leaves with the incisors and clips them with the premolars at the petiole, before being chewed to pieces by the cusped molars. They also store food in their cheek pouches before it is ready to be chewed.
The partially worn molars of Koalas in their prime are optimal for breaking the leaves into small particles, resulting in more efficient stomach digestion and nutrient absorption in the small intestine. This digests the eucalyptus leaves to provide most of the animal’s energy.
Koalas are hindgut fermenters, and their digestive retention can last for up to 100 hours in the wild or up to 200 hours in captivity. This is made possible by their caecum 80 in. long and 4 in. in diameter.
Koalas can hold food particles for longer fermentation if needed. They are more likely keep smaller particles as larger ones take longer to digest.
While hindgut is relatively large, only 10% of the animal’s energy is obtained from digestion in this chamber. The Koala’s metabolic rate is only 50% of the typical mammalian rate, owning to its low energy intake.
They can digest the toxic plant secondary metabolites, phenolic compounds and terpenes present in eucalyptus leaves due to their production of cytochrome P450, which breaks down these poisons in the liver.
The Phascolarctos cinereus or Koala maintains water by absorbing it in the caecum, resulting in drier faecal pellets packed with undigested fibre. It replaces water in its body at a lower rate then in some other species like some possums.
