Male koalas mark their territory by rubbing their chests on a tree. Male koalas have a dark scent gland in the middle of their chest.

The system of democracy was introduced 2 500 years ago in Athens, Greece. The oldest existing governing body operates in Althing in Iceland. It was established in 930 AD.

Pain is measured in units of "dols". The instrument used to measure pain is a "dolorimeter".

AMAZING FACTS