Cows sleep almost as long as humans.
When a man blows his nose, the air speed that comes out under pressure reaches 160 km per hour.
In Africa poachers kill about a hundred elephants every day.
Every 30.000 years riverbeds are deepened by a meter.
In the year 1900, the number of human population was 1.5 million, of whom a quarter lived in Europe.
Geese were the first birds domesticated by man.
