The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Blue eyes are a genetic mutation. Before the mutation occured, all humans had brown eyes.
89
Yawns are more contagious among people with closer relationships.
163
We forget why we have entered a room because passing through doors creates an ‘event boundary’ causing the brain to file away what we were just thinking about.
26
If Earth's life was compressed into 1 year, then humans would have been around for only 2 seconds.
15
Cats have a weak sense of taste. They have only 473 tastebuds, humans have 9,000.
307
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Our Right Lungs takes more air than our left lung.
194