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
The Lion's Mane Jellyfish is the largest jellyfish in the world. They have been swimming in arctic waters since before the dinosaurs (over 650 million years ago).
12
It's possible to die from a broken heart; it's called Stress Cardiomyopathy.
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The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
If you have 1 billion dollars and spend $1,000 every day, it would take you 2,740 years to go broke.
31
Only about 2% of the world population has green eyes.
36
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81