Mars had an oxygen-rich atmosphere around 4 billion years ago
13
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
If aliens located 60-65 million light years away from us, looked at earth through a really powerful telescope today, they would see dinosaurs!
18
Cows can sleep standing up, but they can only dream lying down.
745
The 409 escalators in the London subway cover a distance every week which is approximately equivalent to several trips around the globe!
94
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14