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Yummi
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| [Note Guidelines] Photographer's Note |
Koalas live almost entirely on eucalyptus leaves. This is likely to be an evolutionary adaptation that takes advantage of an otherwise unfilled ecological niche, since eucalyptus leaves are low in protein, high in indigestible substances, and contain phenolic and terpene compounds that are toxic to most species. Like wombats and sloths, koalas have a very low metabolic rate for a mammal (which conserves energy) and rest motionless for about 20 hours a day, sleeping most of that time. They feed at any time of day, but usually at night. An average koala eats 500 grams of eucalyptus leaves each day, chewing them in their powerful jaws to a very fine paste before swallowing. The liver deactivates the toxic components ready for excretion, and the hind gut (especially the caecum) is greatly enlarged to extract the maximum amount of nutrient from the poor quality diet. Much of this is done through bacterial fermentation: when young koalas are being weaned, the mother passes unusually soft faeces rich in these bacteria to pass these essential digestive aids onto her offspring.
Koalas will eat the leaves of a wide range of eucalyptus, and occasionally even some exotic species, but they have firm preferences for particular varieties, which vary from one region to another: in the south Manna Gum, Blue Gum and Swamp Gum are favoured; Grey Gum and Tallowwood are important in the north, and the ubiquitous River Red Gum of the isolated seasonal swamps and watercourses that meander across the dry inland plains allows koalas to exist in surprisingly arid areas. The major factor that determines which of the 800 species of eucalyptus trees koalas eat is the concentration of a group of phenolic toxins called formylated phloroglucinol compounds.
Koalas are almost entirely arboreal. They do not make nests, but sleep in a tree fork or on a branch. They climb using their powerful claws for grip, usually moving quite slowly but can climb rapidly when needed. Koalas will leap confidently from one tree to another if they are reasonably close together. Longer distances are traversed on the ground in a slow but effective waddle. If threatened, koalas break into a surprisingly athletic gallop, heading for the nearest tree and bounding up it to a safe height. There the Koala waits for the intruder to go away with the patience of a creature that routinely sleeps for 18 hours a day. If the intruder attempts to climb the tree to pursue the Koala, it is not unknown for the koala to urinate as a defence mechanism. Koalas are also rather adept at swimming, but this has rarely been witnessed.
Source: Wikipedia.com |
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Hello,
Great KOALA!
Great details!
Ana:)
- KellEy
![Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 188 W: 18 N: 86]](http://i1.treknature.com/misc/g-s-g.gif)
(704) - [2006-03-03 23:18]
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It's so "in the moment". I love the real POV.
![Gold Star Critiquer/Gold Note Writer [C: 985 W: 0 N: 252]](http://i1.treknature.com/misc/g-n-g.gif)
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