All facts — Page 83

We have as many bacteria as human cells.

The body hosts trillions of microorganisms (microbiome) that coexist in symbiosis, vital for immunity and digestion.

The eyes can distinguish 10 million colors.

Cones in the retina allow us to perceive a vast chromatic spectrum, processed uniquely by each brain.

The heart beats about 100,000 times a day.

This results in pumping approximately 7,500 liters of blood daily throughout the body.

Our skin renews itself almost completely every 28 days.

Dead cells from the upper layer of skin (epidermis) are replaced by new cells generated in the lower layers.

Humans are the only animals that blush.

Facial blushing is a complex emotional response associated with self-awareness, dilating facial blood vessels.

The stomach renews its lining every 3 or 4 days.

It produces a new layer of mucus and tissue to protect itself from the extreme acidity of gastric juices.

Tooth enamel is the strongest substance in the body.

It is composed mostly of minerals, making it stronger and more resistant than any bone.

Oysters can change sex.

Many species are sequential hermaphrodites, changing sex depending on water temperature and reproduction needs.

Penguins can drink salt water.

They have a supraorbital gland that filters excess salt from the blood, which is expelled through the beak.

Butterflies taste with their feet.

They have chemoreceptors on their tarsi that allow them to "taste" plants to know where to lay eggs.

Dogs have fingerprints on their noses.

The texture of a dog's nose skin is unique, just like human fingerprints, and can be used for ID.

Cats sleep 70% of their lives.

This behavior is due to their instinct to conserve energy for hunting.

Flamingos are born gray.

Their pink color develops due to carotenoid pigments in their diet rich in algae and shrimp.

Flies taste their food with their feet.

They have taste receptors on their legs, allowing them to know if something is edible as soon as they land.

Giraffes sleep very little.

In the wild, they sleep 30 minutes to 2 hours a day in short naps to stay vigilant against predators.

Sharks are older than trees.

Sharks have swum in the oceans for 400 million years, while the first trees appeared 350 million years ago.

Crocodiles cannot stick out their tongues.

Their tongue is firmly attached to the bottom of the mouth by a membrane, preventing free movement.

Platypuses have no stomach.

The esophagus connects directly to the intestines. Also, females "sweat" milk through their skin.

Bees can recognize and memorize human faces.

They can process complex facial patterns and associate them with previous experiences.

The human body produces about 25 million new cells per second.

Most are red blood cells, which live about 120 days. Over a lifetime, the body produces trillions of cells.

Earth receives 430 quintillion joules from the Sun every hour.

This energy is enough to power human civilization for thousands of years — if we could capture it all.

Dolphins sleep with half their brain shut off.

It's called "unihemispheric sleep". Half the brain rests while the other keeps the dolphin breathing and alert.

The human body contains about 37.2 trillion cells.

This estimate was calculated in 2013 by Israeli researchers. Most are red blood cells.

Hot water freezes faster than cold — Mpemba Effect.

Discovered by a Tanzanian student in the 1960s, the phenomenon is still not fully explained by science.