Gioca STEMAnimals

Animals · Australia and Oceania

Koala

Phascolarctos cinereus

Nineteen hours a day without moving

A koala wedged in the fork of a eucalyptus branch, the position where it spends most of its day.
A koala wedged in the fork of a eucalyptus branch, the position where it spends most of its day.
  • Status: Threatened
  • Eucalyptus forests of the eastern Australian coast

Numbers

Weight
20 lbfrom 13 to 26 lb, with males about 50 percent larger than females
Length
28 infrom 24 to 33 in
Lifespan
20 yearsWikidata reports 10 years, reference material indicates about twenty
Hours motionless
19 hours a dayfrom 18 to 19, mostly sleeping
Leaves per day
1 lbeucalyptus leaves and buds
Weight at birth
0,2 ozabout three quarters of an inch long

Ten fun facts

  1. it almost never drinks water and gets all the hydration it needs directly from the eucalyptus leaves it eats.

  2. it chews its food so thoroughly that it only swallows the leaves after grinding them into a fine paste.

  3. its cecum is enormous and functions as a fermentation chamber where microscopic organisms digest plant cellulose.

  4. young joey koalas eat a soft stool from the mother to gain the gut bacteria needed to digest eucalyptus.

  5. there are only two teats inside the pouch, which is why almost every litter consists of a single joey.

  6. its pouch opens downward, unlike those of other marsupials, yet the tiny joey never falls out.

  7. it climbs down to the ground occasionally to swallow soil, bark, and small stones that assist with digestion.

  8. essential oils from eucalyptus soak its fur and act as a natural shield against harmful parasites.

  9. giant koalas lived in southern Australia until fifty thousand years ago and are known today only through fossils.

  10. in 2019 the Australian population was estimated at eighty thousand individuals, declining due to forest loss.

The quiz answers

The first one is the question printed in your book: here is the answer. The other four are extra.

Question 1 of 5★ this one is in your book

How many hours a day does the koala stay motionless?

Question 2 of 5

What does it feed on almost exclusively?

Question 3 of 5

How does the joey become able to digest eucalyptus?

Question 4 of 5

How much does a newborn koala weigh?

Question 5 of 5

Which trait does it share with primates?

Try it yourself

Experiment 1

Weigh one pound of salad leaves on a kitchen scale to see how many leaves a koala eats in a single day.

Experiment 2

Time nineteen hours on a wall clock and list how many different activities you finish while a koala stays completely still.

Experiment 3

Place a fifth of an ounce of rice on a plate and measure three quarters of an inch with a ruler to see a newborn koala.

Data from Wikidata (Q36101) and Wikipedia (Koala).