Earth is home to more than 1 million known animal species, each one representing an ancient tome of biological trivia. Much of this random knowledge gets lost in the ether, leaving us to speculate about things like dinosaur divorce rates or amphibian dance moves. But we still catch an awful lot, providing us with plenty of interesting — if not always actionable — facts about our fellow fauna.
The list below is a tribute to such trivia. From extinct penguins to newly identified wasps, these tidbits reflect the depth of our own species' curiosity about nature — and our skill in shedding new light on it. As you peruse these facts, imagine all that went into discovering each one. We embrace their randomness here, but most hail from a robust body of knowledge about the animal in question.
So without further ado, here are 36 random animal facts that may interest you:
1. A type of "immortal" jellyfish is capable of cheating death indefinitely.
2. Octopuses have three hearts.
3. Butterflies can taste with their feet.
4. Cats and horses are highly susceptible to black widow venom, but dogs are relatively resistant. Sheep and rabbits are apparently immune.
5. Sharks kill fewer than 10 people per year. Humans kill about 100 million sharks per year.
6. Wild dolphins call each other by name.
7. Young goats pick up accents from each other.
8. Humpback whale songs spread like "cultural ripples from one population to another."
9. Tardigrades are extremely durable microscopic animals that exist all over Earth. They can survive any of the following: 300 degrees Fahrenheit (149 Celsius), -458 degrees F (-272 C), the vacuum of space, pressure six times stronger than the ocean floor and more than a decade without food.
10. Horses use facial expressions to communicate with each other.
11. Elephants have a specific alarm call that means "human."
12. Squirrels can't burp or vomit.
13. Less time separates the existence of humans and the tyrannosaurus rex than the T-rex and the stegosaurus.
14. There's a place on Earth where seagulls prey on right whales.
15. Owls don't have eyeballs. They have eye tubes.
16. Animals with smaller bodies and faster metabolism see in slow motion.
17. Dogs' sense of smell is about 100,000 times stronger than humans', but they have just one-sixth our number of taste buds.
18. The extinct colossus penguin stood as tall as LeBron James.
19. Male gentoo and Adelie penguins "propose" to females by giving them a pebble.
20. Azara's owl monkeys are more monogamous than humans.
21. Barn owls are normally monogamous, but about 25 percent of mated pairs "divorce."
22. A group of parrots is known as a pandemonium.
23. Polar bears have black skin.
24. Reindeer eyeballs turn blue in winter to help them see at lower light levels.
25. A human brain operates on about 15 watts.
26. Warmer weather causes more turtles to be born female than male.
27. African buffalo herds display voting behavior, in which individuals register their travel preference by standing up, looking in one direction and then lying back down. Only adult females can vote.
29. Honeybees can flap their wings 200 times every second.
30. The claws of a mantis shrimp can accelerate as quickly as a .22-caliber bullet.
33. The recently discovered bone-house wasp stuffs the walls of its nest with dead ants.
34. By eating pest insects, bats save the U.S. agriculture industry an estimated $3 billion per year.
35. Fourteen new species of dancing frogs were discovered in 2014, raising the global number of known dancing-frog species to 24.
36. A sea lion is the first nonhuman mammal with a proven ability to keep a beat.
Illustrations by Russell McLendon/MNN