When Australia separated from Gondwanaland, it was like a giant Noah's Ark adrift on the seas,
and the animals on it had to adapt in isolation from the rest.
The trees also adapted, particularly the eucalyptus tree, which quickly spread.
Some marsupials had no problems in squeezing the juice out of this situation.
The Koala bear managed the impossible: it adapted to the point where all it eats are eucalyptus leaves.
Eucalyptus leaves are poor quality food, indigestible and full of toxins,
but the koala has managed to survive on them.
Their digestive process is long, and the koalas go about their business without wasting any energy.
This is part of their metabolic strategy.
They can survive on only 16 ounces of leaves a day,
but of course they move very slowly to avoid wasting energy.
They are pretty clumsy on the ground and very vulnerable,
so they only go down to the ground in order to move over to another tree.
The koala is indifferent to the rhythm of the bustling world.
And even more so when it's raising its young.
Raising its young takes time.
The young koalas suckle in the marsupial bag until they are 6 months old.
When they are weaned, they are initiated into the art of leaf eating.
For this, their mother feeds them with her own feces,
a purée which provides them with the microorganisms they need to digest the toxic eucalyptus leaves.
After weaning, the young koalas leave their mothers to live on their own in these woodlands.