Your thumb is about the same size as your nose.
124
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
The oldest glowing lightbulb was first switched on in 1901 and lives in fire stations in Livermore, CA. It is known as the Centennial Light.
118
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
There are so many kinds of apples that if you ate a new one everyday, it would take over 20 years to try them all.
34
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14