Animal Facts

Cows are thought to contribute 20% of the world's methane emissions.

Dairy cows can belch 400 to 500 litres (88 to 110 gallons) of methane gas per day. That is 200 times more than a person.

In a year they emit 9 kilograms (20 pounds) of smog, forming gases known as volatile organic compounds (VOCs). That is more than a car or a light truck.

Sparrows know how to protect themselves from disease.

When an outbreak of Malaria hit Calcutta, in India, the sparrows started lining their nests with leaves from the Krishnachura tree.

They then ate the leaves, which contained quinine, which killed the malaria parasite.

Male Canaries can drive females wild with their singing.

The birds can produce a spectacular rapid-fire trilling, in which they vibrate notes 16 times per second.

Such is the power of the canary's virtuoso voice, females who hear it immediately adopt a posture that signals they are ready for sex.

Being bald is not a total disadvantage in the lion world.

Male lions that live in Tsavo National Park in Kenya are unusual in that they have sparse blond hair, a beard, hairy chest and sideburns - but no mane.

Despite this, they have shown they have an active sex life and tend to have an entire pride of females to themselves. Lions with manes often have to share their mates with one to three males in the pride.

This has led some to wonder whether, rather like in the human world, thinning on top may in fact be a symbol of virility.