How many hearts does an octopus have?
Three — two pump blood through the gills, one to the rest of the body. Their blood is blue, based on copper instead of iron.
Just know.
12 facts — science, space, the body, the world. No fluff.Does honey spoil?
Archaeologists have tasted 3,000-year-old honey from Egyptian tombs and found it edible. Low water and high acidity make it hostile to microbes.
Is a tongue print unique?
Like fingerprints, tongue prints are considered unique. unlike fingerprints, nobody has built a tongue scanner — the tongue is too mobile and impolite to press on glass.
Are sharks older than trees?
Yes — sharks appeared about 450 million years ago, trees around 390 million. Sharks also predate Saturn's rings, which may be only 100–400 million years old.
Are bananas radioactive?
Mildly — bananas are rich in potassium, and a tiny fraction of natural potassium is radioactive. The dose is harmless; the "banana equivalent dose" is a physics joke unit.
Why are flamingos pink?
They're born grey and turn pink from carotenoids in the brine shrimp and algae they eat. Zoo flamingos fade without supplements.
Where does a woodpecker's tongue go?
It's so long it wraps around the skull and anchors over the eyes — acting as a shock absorber for a bird that hammers up to 20 times a second.
What is the oldest living tree?
A Great Basin bristlecone pine named Methuselah — about 4,850 years old, older than the Egyptian pyramids. Its exact location in California is kept secret.
What is the heaviest living thing?
Pando, a quaking aspen grove in Utah — 47,000 stems but one root system and one genetic individual, weighing about 6,000 tonnes and possibly 14,000 years old.
Why do cats purr?
Not only contentment — cats also purr when injured or stressed, and the 25–150 Hz vibration may promote bone and tissue healing. It's a signal and self-repair tool.
Why do koalas sleep so much?
Eucalyptus leaves are low-calorie and mildly toxic, so koalas sleep up to 22 hours a day to budget energy. Their digestive system takes days per meal.
How many ants are there?
A 2022 estimate put ants at about 20 quadrillion (2×10^16) — outweighing all wild birds and mammals combined.