Crows and ravens can recognize human faces, remember them for years, and even pass this knowledge to their offspring.

#animals

The Roman Empire at its peak stretched across three continents, ruling over about 60 million people — nearly a fifth of the world’s population at the time.

#history

The “placebo effect” is so strong that even when people know they are taking a placebo, they can still experience real improvements in health.

#psychology

The average adult human body contains about 37 trillion cells, all working together to keep us alive.

#science

If two pieces of the same type of metal touch in space, they will fuse together permanently in a process called “cold welding.”

#space

Laughter releases endorphins, lowers blood pressure, and reduces stress hormones — it’s a natural medicine for the body.

#psychology

People who sleep less than 6 hours a night have a higher risk of developing heart disease, diabetes, and weakened immune function.

#psychology

The fingerprints of a koala are so similar to humans that even forensic experts can confuse them.

#animals