94 Fun Facts About Animals

What is the largest living species of lizard?

The Komodo dragon is the largest living lizard: males can reach 3 m and about 150 kg, and a 1926 collecting expedition to its islands helped inspire the film King Kong.

Which bird is known for its ability to mimic human speech?

The African grey parrot is the best-known mimic of human speech; Alex, the African grey studied by Irene Pepperberg for 30 years, used about 100 words.

What type of animal is a seahorse?

A seahorse is a fish: all 46 species belong to the genus Hippocampus, and they are highly modified pipefish that swim upright.

Which mammal is known for having the longest gestation period?

The African elephant has the longest gestation of any mammal, about 22 months; a cow then usually waits four years or more before giving birth again.

What is a group of wolves called?

A group of wolves is a pack, typically a breeding pair and their offspring from the last few years; packs cooperate to bring down prey as large as moose.

Which ocean creature has three hearts?

Octopuses have three hearts: two branchial hearts that pump blood to the gills, and one systemic heart that pumps oxygenated blood to the rest of the body.

What is the fastest land animal?

The cheetah is the fastest land animal, capable of reaching speeds up to 70 mph in short bursts. Their flexible spine, large nasal passages, and semi-retractable claws all contribute to their speed.

Which animal produces the loudest sound in the animal kingdom?

The sperm whale produces the loudest sound of any animal, with clicks reaching up to 230 decibels. These clicks are used for echolocation when hunting in deep ocean waters.

What is the primary diet of a koala?

Koalas feed almost entirely on eucalyptus leaves, which are low in nutrients and toxic to most animals; of more than 600 eucalyptus species they favour only around 30.

Which is the only penguin species found north of the equator?

The Galápagos penguin lives only on the Galápagos Islands, which straddle the equator; most of the population is on Fernandina and western Isabela, whose northern tip lies in the Northern Hemisphere.

What is the name for a baby kangaroo?

A baby kangaroo is a joey; it is only about 2 cm long at birth and crawls unaided into the pouch, where it stays for months before venturing out.

What is a salmon's hatch-in-fresh-water, mature-at-sea, return-to-spawn life pattern called?

Anadromy is the pattern of hatching in fresh water, maturing at sea and returning to spawn; most salmon come back to their natal stream, though some stray into other rivers.

Along with the bonobo, which primate is one of humankind's two closest living relatives?

The chimpanzee and the bonobo, the two Pan species, are our closest living relatives; the chimpanzee draft genome published in 2005 was about 99% identical to the human genome in aligned sequence.

What is the largest species of bear?

The polar bear is generally considered the largest bear species. Adult males can weigh up to 1,500 pounds and stand over 10 feet tall on their hind legs. The Kodiak bear is a close rival in size.

What is the only mammal capable of true sustained flight?

Bats are the only mammals capable of true sustained flight. Flying squirrels, sugar gliders, and colugos can only glide — bats actively flap their wings to generate lift and thrust.

What is the largest animal known to have ever existed?

The blue whale is the largest animal known to have existed: confirmed specimens reach about 30 m and up to 200 tonnes, heavier than any dinosaur.

What is the largest living fish in the world?

The whale shark is the largest living fish, growing up to 40 feet or more in length. Despite their enormous size, whale sharks are filter feeders that eat plankton, fish eggs, and small fish.

Koalas, on their low-energy diet, sleep up to how many hours a day?

Koalas sleep about 20 hours a day, often eating and sleeping in the same tree, because eucalyptus leaves yield so little energy; wild three-toed sloths sleep under ten.

Where are a cricket's ears located?

Crickets have their hearing organs (tympanal organs) located on their front legs, just below the knee joint. These flat, oval membranes detect the sound vibrations of other crickets' calls.

Which seabird's yearly round trip from the far north to waters around the South Pole is the longest migration known?

One tagged bird from the Farne Islands covered 96,000 km in ten months, dipping halfway across the South Pacific before heading home.

What is a group of flamingos called?

A group of flamingos is a flamboyance (a 'stand' is also used); the birds feed with their heads upside down, filtering small prey from the water through their bills.

What is the largest species of penguin?

The emperor penguin is the largest penguin, standing about 100 cm and weighing up to 45 kg; males fast for over two months through the Antarctic winter while incubating a single egg on their feet.

Sharks sense hidden prey through the ampullae of Lorenzini, organs of which sense?

Electroreception lets sharks detect the faint electric fields every living animal produces; the jelly-filled pores called ampullae of Lorenzini can sense a fish buried beneath sand.

Which animal can rotate its head almost 270 degrees?

Owls can rotate their heads up to 270 degrees in either direction. They have 14 neck vertebrae (twice as many as humans) and specialized blood vessels that prevent loss of blood flow during rotation.

Which species of whale is known for its complex, haunting songs?

Humpback whales are famous for their long, structured songs; only the males sing, and a song can last up to about 30 minutes and be repeated for hours.

What structure do birds have instead of teeth for grinding food?

Birds use a muscular organ called the gizzard to grind food, often aided by small stones or grit they swallow. Since birds lack teeth, the gizzard serves as a mechanical stomach that crushes hard foods.

Which endangered great ape is found only on the islands of Borneo and Sumatra?

Orangutans are found only on the Southeast Asian islands of Borneo and Sumatra. They are the largest arboreal mammals and are critically endangered due to habitat loss from deforestation and palm oil plantations.

What is the hard outer covering of insects called?

Insects have an exoskeleton made of chitin, a tough polysaccharide. This external skeleton provides structural support, protection from predators, and prevents water loss. Insects must molt to grow.

What is the primary reason flamingos are pink?

Carotenoids in the animal and plant plankton they eat are broken down into pigments by liver enzymes; a bird deprived of them fades to pale.

Which Australian bird incubates its eggs in a large mound of rotting leaf litter?

The malleefowl, a megapode, buries its eggs in a mound of sand and decomposing leaf litter; the male tests the temperature with its bill and adds or removes material to hold it near 33 °C.

Which deep-sea creature produces its own light through bioluminescence?

The deep-sea anglerfish dangles a glowing lure, the esca, on a modified dorsal-fin ray; its light comes from bioluminescent bacteria living inside the lure.

Which animal has the thickest fur of any mammal?

Sea otters have the densest fur of any mammal, with up to one million hair follicles per square inch. Unlike most marine mammals, they have no blubber layer and rely entirely on their fur for insulation in cold ocean waters.

What is the name for the phenomenon where certain species of cuckoo lay their eggs in other birds' nests?

Brood parasitism is a reproductive strategy where the cuckoo lays its eggs in the nests of other bird species, tricking them into raising the cuckoo's young. The cuckoo chick often pushes the host's eggs out of the nest.

What is a baby dog called?

A baby dog is a puppy, a term generally used until about a year old; 'pup' is also used loosely for the young of wolves, seals, rats and sharks.

How many legs does a spider have?

A spider has 8 legs, each built from seven segments; four pairs of walking legs and no antennae are defining features of arachnids.

Which of these animals is the tallest?

Giraffes stand 4.3 to 5.7 m, and the heart has to generate about double a human's blood pressure to push blood up to the brain.

Which crustacean strikes with club-like appendages that accelerate at around 10,000 g?

The mantis shrimp's blow is so fast it creates cavitation bubbles in the water, reaching 23 metres per second from a standing start.

Which bird has the greatest wingspan of any living bird?

The wandering albatross has the greatest wingspan of any living bird, up to about 3.5 m; some individuals circle the Southern Ocean three times in a single year.

What is the term for the organ in pit vipers that detects infrared radiation from prey?

The loreal pit, one between eye and nostril on each side of a pit viper's head, is a heat-sensing organ that picks up infrared radiation from warm-blooded prey.

Which insect was the first animal shown to orient itself by the Milky Way?

Dung beetles were shown in 2013 to steer by the Milky Way; an African species was also the first animal known to navigate by the polarisation pattern of moonlight, rolling its ball in a straight line.

Which marine animal stores the stinging cells of the Portuguese man o' war it eats for its own defence?

The blue dragon sea slug, Glaucus atlanticus, keeps the most venomous nematocysts of the man o' war in cnidosacs at the tips of its cerata, a process called kleptocnidy.

Which vertebrate has the longest known lifespan, estimated at 272 to 510 years, and only reaches maturity at around 150?

The Greenland shark is thought to mature at around 150 years old, and its pups are born after a gestation estimated at 8 to 18 years.

Which bird has been shown to build compound tools by slotting together two to four short branches?

New Caledonian crows, in a 2018 Max Planck and Oxford experiment, slotted two to four short pieces into one long tool to reach food, a feat previously seen only in great apes.

Which deep-sea fish has a transparent head and looks upward through its skull?

The barreleye, Macropinna microstoma, has tubular eyes inside a transparent fluid-filled dome; they normally point upward but can swivel forward, and the dome may shield them from siphonophore stings.

Which animal's stripes are thought mainly to deter biting flies rather than to camouflage?

Zebra stripes are unique to each individual, like a fingerprint; the strongest evidence for why they exist points to confusing biting flies rather than to camouflage.

The Komodo dragon is native to a handful of islands in which country?

Komodo dragons live only on Komodo, Rinca, Flores and a few neighbouring islands of Indonesia, most of them inside Komodo National Park, established in 1980.

How many legs does an insect have?

An insect has six legs, three pairs all attached to the thorax; a body in three segments — head, thorax and abdomen — is the other defining feature.

What is a group of lions called?

A group of lions is a pride, built around related females and their cubs, with one or a few adult males who must fight to keep their place.

Which bird is the fastest animal on the planet when diving?

The peregrine falcon's hunting stoop exceeds 320 km/h, making it the fastest animal on Earth; a trained peregrine named Frightful was clocked at about 390 km/h in 2005.

Which life-cycle feature do amphibians have that reptiles lack?

Metamorphosis from gilled larvae: tadpoles breathe with gills before growing lungs and legs, a switch a reptile never makes.

Which egg-laying mammal delivers a painful venom through a spur on the male's hind foot?

The male platypus has a spur on each hind foot linked to a venom gland; the venom is not lethal to humans but causes pain that can last weeks, and is thought to serve in fights between rival males.

What is the largest living species of reptile?

The saltwater crocodile is the largest living reptile: big males exceed 5 m and 1,000 kg, and the species ranges from eastern India through Southeast Asia to northern Australia.

Which flightless bird lays an egg that can weigh a fifth of the mother's body weight?

The kiwi, a chicken-sized bird, lays an egg about six times the size of a hen's, roughly a fifth of its own body weight; the female barely eats in the final days because there is no room.

Which of India's 'Big Four' snakes makes a sizzling warning by rubbing its keeled scales together?

The saw-scaled viper coils and rubs its serrated, keeled scales together to produce a sizzling rasp — the habit that gives the genus Echis its common name — and it bites readily when disturbed.

How many compartments does a cow's stomach have?

A cow's stomach has four compartments — rumen, reticulum, omasum and abomasum; microbes in the rumen ferment grass, and the abomasum is the true acid-secreting stomach.

What unique defense mechanism does the Texas horned lizard use?

The Texas horned lizard squirts blood from its eyes: it raises blood pressure in its head until vessels around the eyelids burst, and the foul-tasting spray, reaching up to 1.5 m, deters dogs and coyotes.

Which ant carries vegetation up to 50 times its own body weight home to feed the fungus it farms?

Leafcutter ants never eat the leaves themselves; they feed them to a fungus in underground gardens and eat the fungus, a partnership that has lasted tens of millions of years.

Chironex fleckeri, blamed for dozens of deaths in Australian waters, is what kind of animal?

Chironex fleckeri is a box jellyfish whose tentacles can stop a heart within minutes; northern Australian beaches close in 'stinger season' and keep vinegar on hand to neutralise unfired stinging cells.

Adélie penguins build their rough nests out of what material?

Adélie penguins build nests of small stones; good ones are scarce on the bare Antarctic shore, so neighbours steal from each other constantly, and a well-chosen stone is a courtship gift.

How do dolphins sleep without drowning?

One eye stays open, opposite the resting hemisphere, so the animal keeps surfacing to breathe and watching for sharks.

Which animal can regenerate its entire body from a tiny fragment?

A planarian flatworm can regrow a whole worm within weeks from a piece as small as 1/279th of the original, which led one naturalist to call it 'immortal under the edge of a knife'.

Which is the only primate known to be venomous?

The slow loris is the only venomous primate: it licks a gland on its upper arm and mixes the secretion with saliva, giving a bite that can send a human into anaphylactic shock.

Lemurs live wild only on Madagascar, an island lying off the coast of which continent?

Madagascar lies in the Indian Ocean about 400 km off the east coast of Africa; its long isolation let more than a hundred lemur species evolve, from the mouse lemur to the indri.

Sharks have no swim bladder; which oil-rich organ gives them buoyancy instead?

A shark's large oil-rich liver, up to a quarter of its body weight in some species, lowers its density in place of a swim bladder; lift from the pectoral fins does the rest.

Able to sprint at about 70 km/h, which is the fastest bird on land?

The ostrich sprints at about 70 km/h, the fastest of any bird on land; it is also the heaviest living bird and lays the largest egg of any living bird, though relative to body size that egg is the smallest.

What is the world's smallest mammal by weight?

The Etruscan shrew weighs about 1.8 grams, roughly a paperclip, the lightest of all mammals; the bumblebee bat claims the title by skull size and body length instead.

Which bird is the only one whose bill is longer than its body?

The sword-billed hummingbird of the Andes carries a bill up to about 12 cm, longer than the rest of its body, to reach nectar in long-tubed flowers; it has to preen with its feet.

What adaptation allows the wood frog to survive being frozen solid?

Urea and glucose act as cryoprotectants that keep ice from forming inside its cells; up to about two thirds of its body water can freeze and the heart stops until spring.

What is the only snake that builds a nest for its eggs?

The king cobra is the only snake known to build a nest: the female rakes dry leaf litter into a mound, lays inside it and guards it through incubation, leaving just before the eggs hatch.

Which animal has horizontal, rectangular pupils?

Goats have horizontal, rectangular pupils that give a grazing animal a wide panoramic view and stay level with the horizon as the head tilts down; cats and crocodiles have vertical slits.

What percentage of all known animal species are invertebrates?

Roughly 97% of known animal species are invertebrates; insects alone number about a million described species, while all vertebrates together total only around 66,000.

Which animal can survive in the vacuum of space?

Tardigrades, or water bears, curl into a dehydrated 'tun' and ride out vacuum, radiation and extreme temperatures; in 2007 dehydrated specimens spent ten days in open space on the FOTON-M3 mission and revived.

Which great ape did Dian Fossey study in the Virunga mountains for 18 years?

Dian Fossey studied mountain gorillas at Karisoke in Rwanda's Virunga mountains from 1967 until her murder in 1985; the 1989 census found about 620, and the 2018 census counted 1,063.

Which amphibious goby uses its pectoral fins to skip across mudflats and even clamber onto low branches?

Mudskippers, amphibious gobies, breathe through their skin and the lining of the mouth and throat when out of water, much as a frog does, and some dig burrows that hold a pocket of air.

Which animal's fingerprints are so like a human's that even experts struggle to tell them apart?

Koalas have ridged fingerprints nearly indistinguishable from a human's even under a microscope — convergent evolution in a marsupial and a primate that both grip branches.

Which crustacean has the greatest leg span of any arthropod, up to about 3.7 m?

The Japanese spider crab, living off Japan at depths of about 50 to 600 m, spans up to 3.7 m from claw to claw, the widest of any arthropod, though its body is only around 40 cm across.

Which is the longest-lived mammal, with individuals estimated at over 200 years?

The bowhead whale is the longest-lived mammal: amino-acid dating of eye lenses put one at about 211 years, and a bowhead killed in 2007 carried a harpoon fragment made in the 1880s.

Which insect undergoes incomplete metamorphosis, skipping the pupal stage?

The grasshopper hatches as a wingless nymph or 'hopper' and moults about five times, each instar a little more adult with growing wing buds; there is no pupal stage.

Which bird can fly backwards?

The hummingbird is the only bird that truly flies backwards: its wings rotate at the shoulder and beat around 50 to 80 times a second, giving helicopter-like control in any direction.

What is the name for a group of crows?

A group of crows is a murder; most such collective nouns come from fanciful 15th-century lists of hunting terms, notably the Book of St Albans of 1486.

What is Turritopsis dohrnii, a hydrozoan that can revert to its juvenile polyp stage, nicknamed?

Turritopsis dohrnii, the immortal jellyfish, can collapse as a stressed or injured adult into a blob that regrows as a polyp colony, in effect starting life over, though most get eaten in the wild anyway.

Bottlenose dolphins in Shark Bay, Western Australia, wear what on their snouts while rooting for food?

The dolphins carry a marine sponge over the snout to protect it while rooting in the seabed; 'sponging' passes from mother to calf, one of the clearest cases of culture in a non-human animal.

What is the most trafficked mammal in the world?

Pangolins are the most trafficked mammals, with an estimated 100,000 a year taken for China and Vietnam, prized for scales that are only keratin, the stuff of fingernails.

In which reef fish does the breeding male turn female when the dominant female of the group disappears?

Clownfish are protandrous hermaphrodites: when the dominant female dies the breeding male turns female and the largest non-breeder becomes the new male, which makes the plot of Finding Nemo biologically awkward.

Hippos ooze a red fluid nicknamed 'blood sweat'. What does it actually do?

It comes out colourless and turns red-orange within minutes; the two acidic pigments in it absorb ultraviolet light and inhibit bacteria on their skin.

What is the term for animals that are most active during twilight hours (dawn and dusk)?

Crepuscular animals such as deer, rabbits and many cats are most active at dawn and dusk, dodging both daytime and night-time hunters; dawn specialists are matutinal, dusk ones vespertine.

Which group of mammals are the closest living relatives of the hippopotamus?

Molecular studies place hippos and whales together in the clade Whippomorpha; the two lines shared a common ancestor more than 50 million years ago, well after their split from pigs.

The narwhal's spiralled tusk, up to three metres long, is actually what?

The tusk is a protruding left canine tooth that grows through the upper lip in a spiral; it is thought to serve as a weapon, a mating display and, with its millions of nerve endings, a sensor of water salinity.

Which South American semiaquatic herbivore is the largest living rodent?

The capybara grazes on grasses and aquatic plants near fresh water, and lives in every South American country except Chile.

How does the archerfish catch insects perched on overhanging leaves?

It spits jets of water to knock them down from a specialised mouth; most of the ten species live in freshwater streams and wetlands, a few tolerating brackish water.

Up to roughly how many volts can an electric eel deliver in a shock?

Electrophorus voltai, described in 2019, was recorded discharging 860 volts, the strongest of any animal; eighteenth-century studies of electric fish helped inspire Volta's 1800 battery, and despite the name it is a knifefish, not a true eel.

The aye-aye of Madagascar taps on wood and then extracts grubs using which unusual feature?

The aye-aye's long, thin middle finger taps the wood and then hooks grubs out of the hole its ever-growing rodent-like incisors have gnawed; it is the world's largest nocturnal primate.

The bombardier beetle defends itself by ejecting a chemical spray heated to nearly what temperature?

Hydroquinone and hydrogen peroxide react explosively in the beetle's glands, heating the spray to about 100 °C — the boiling point of water — with a popping sound; the blast can kill attacking insects.

Which burrowing African mammal is almost cold-blooded, feels no pain in its skin and resists cancer?

The naked mole-rat is also eusocial, living in colonies with a single breeding queen much like ants or bees, and it can live past 30 years, far longer than any other rodent of its size.