The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Your thumb is about the same size as your nose.
124
In the last 7 years, humanity has discovered 43 potentially habitable planets.
14
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
Cows can sleep standing up, but they can only dream lying down.
745
If Earth's history was condensed into twenty-four hours, life would've appeared at around 4am, land plants at 10:24pm, dinosaur extinction at 11:41pm, and human history would’ve began at 11:58:43pm.
21