100 Fun Facts About Animal Kingdom

Which bird has the greatest wingspan of any living species?

The wandering albatross has the largest wingspan of any living bird, averaging about 3 metres; it rides the ocean winds for hours without a single wingbeat, crossing vast distances on very little energy.

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

Zebra stripes are unique to each animal, and why they exist is still argued over; experiments with striped coats on horses point to confusing biting flies rather than camouflage.

The Komodo dragon, the world's largest lizard, is native to a handful of islands in which country?

Indonesia is the Komodo dragon's only wild home, on Komodo, Rinca, Flores and a few nearby islets; females kept apart from males in zoos have laid eggs that hatched without any mating.

Which of these animals is an insect rather than an arachnid?

The flea is an insect, with six legs in three pairs; ticks, scorpions and tarantulas are eight-legged arachnids, though a tick hatches with only six legs and gains the last pair after its first blood meal.

Which ocean creature has three hearts?

An octopus has three hearts: two pump blood through the gills and one drives it round the body; the main heart stops when it swims, one reason it prefers to crawl.

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 rated the fastest animal on Earth when diving?

The peregrine falcon's hunting dive, or stoop, is credited with more than 320 km/h; it strikes prey in mid-air with a clenched foot, then turns to catch it as it falls.

What is the only mammal capable of true sustained flight?

Bats are the only mammals with powered flight; flying squirrels, colugos and sugar gliders only glide. A bat's wing is a hand, skin stretched over long finger bones, so it can flex and reshape it in mid-air.

Which animal produces the loudest sound of any living creature?

The sperm whale's clicks reach about 236 decibels underwater, the loudest sound measured from any animal; it uses them as sonar to find prey on dives into total darkness.

What distinguishes amphibians from reptiles in their life cycle?

Amphibians undergo metamorphosis from gilled larvae: a tadpole breathes with gills before growing lungs and legs, while a reptile hatches as a miniature adult and never makes that switch.

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

The male platypus carries a venomous spur on each hind foot; the venom is not lethal to humans but causes pain that can last weeks, and is thought to be used against rival males in the breeding season.

Which filter-feeding giant, reliably measured at 18.8 metres, is the largest fish alive?

The whale shark is the largest living fish, with one individual reliably measured at 18.8 metres; despite its bulk it strains plankton through its gills and is harmless to the snorkellers who swim with it off Mexico and the Philippines.

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

The kiwi is about the size of a chicken, yet its egg fills 15 to 20 per cent of the female's body; while it grows she has to eat three times her usual amount of food.

Which of India's 'Big Four' venomous snakes warns enemies with a rasping sizzle made by rubbing its coils together?

The saw-scaled viper is named for the serrated ridges on its side scales; looped into coils, it rubs them together to sizzle like water on a hot plate. With the cobra, krait and Russell's viper it makes up India's 'Big Four'.

Flamingos get their pink colour from carotenoid pigments in which food?

Flamingos get their carotenoids from brine shrimp and the algae those shrimp eat, filtered from the water with upside-down bills; chicks hatch grey and turn pink only as the pigments build up.

Which mammal has the longest pregnancy, carrying its calf for about 22 months?

The African elephant's gestation lasts around 22 months, the longest of any mammal; the newborn can stand and walk within the hour, and its mother usually waits about four years before her next calf.

What startling defence does the Texas horned lizard use against coyotes and dogs?

The Texas horned lizard squirts blood from its eyes: it raises the pressure in its head until tiny vessels around the eyelids burst, firing a jet that tastes foul to dogs, coyotes and wolves.

Which ant farms an edible fungus in vast underground gardens?

Leafcutter ants don't eat the leaves they carry home: they chew them up to feed a fungus garden, and the fungus feeds the colony's young.

Chironex fleckeri, whose sting can kill a swimmer within minutes off northern Australia, is what kind of animal?

Chironex fleckeri is a box jellyfish, the most venomous jellyfish known; unlike its drifting cousins it has clusters of true eyes with lenses and swims with purpose, steering around obstacles.

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 whenever a back is turned.

How do dolphins sleep without drowning?

One brain hemisphere sleeps at a time in a dolphin, and the eye opposite the resting half closes while the other keeps watch, so the animal goes on surfacing to breathe and looking out for predators.

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

A planarian flatworm can regrow whole from a sliver as small as 1/279th of its body, head and brain included, because adult stem cells called neoblasts are spread all through it.

What is the fastest land animal over short distances?

The cheetah reaches around 100 km/h in bursts of a few hundred metres, thanks to a long, flexible spine that stretches its stride and blunt claws that stay out and grip like running spikes.

Along with the common chimpanzee, which primate is our closest living relative?

The bonobo and the chimpanzee are the two Pan species; they split from each other only after their shared line had split from ours, so neither is any closer to us than the other.

Lemurs evolved in isolation on Madagascar, an island lying off the coast of which continent?

Madagascar lies off the southeast coast of Africa; cut off there and shaped by its sharply seasonal climate, lemurs evolved into about a hundred species, from the mouse lemur to the indri.

Which deep-sea creature has the largest eyes in the animal kingdom?

The colossal squid has the largest eyes of any living animal, about 27 cm across, the size of a dinner plate; they seem built to catch the faint glow stirred up by a hunting whale in time to flee.

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 land animal, though relative to body size that egg is small.

Which tiny insect-eater, at about two grams, is usually ranked the world's lightest mammal?

The Etruscan shrew, at around 2 grams, is usually ranked the lightest of all mammals; the bumblebee bat of Thailand weighs about the same but is shorter, so the two share the 'smallest' title.

Which bird migrates the longest distance annually?

The Arctic tern flies from the Arctic to the Antarctic and back each year, a round trip tracked at 70,000 to 90,000 km and the longest known migration; its reward is two summers and more daylight than any other creature.

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

Glucose floods its tissues from the liver as the first ice forms, a sugary antifreeze that stops the wood frog's cells freezing inside; its heart and breathing then stop until the thaw.

Which mammal has the densest fur of any animal?

The sea otter has the densest fur of any animal, up to a million hairs per square inch; with no blubber to fall back on it relies on air trapped in that fur and spends hours grooming it.

Which venomous snake is the only one known to build a nest for its eggs?

The king cobra is the only snake known to build a nest: the female drags dead leaves into a mound with a loop of her body, lays her eggs inside and stays to guard them.

Which animal can shoot out a tongue longer than its own body to snag prey?

A chameleon's tongue, longer than its body in many species, is launched by elastic recoil at accelerations of hundreds of metres per second squared; the smaller the species, the proportionately longer its reach.

What percentage of all known animal species are invertebrates?

About 97 per cent of known animal species are invertebrates, most of them insects; only around 66,000 described vertebrate species stand against well over a million animals without backbones.

Which animal can survive in the vacuum of space?

Tardigrades, or water bears, dry out into a dormant 'tun'; in 2007 dried ones were exposed to open space outside the Russian FOTON-M3 capsule, and most of those shielded from the Sun's ultraviolet revived when rewetted.

Which great ape, studied by Dian Fossey, survives only in the Virunga volcanoes and Uganda's Bwindi forest?

The mountain gorilla climbed from about 680 animals in 2008 to more than 1,000 by 2018, thanks to anti-poaching patrols and vets who remove snares; that year it was moved off the critically endangered list.

Which amphibious fish uses its pectoral fins to crawl over tidal flats and climb mangrove roots?

Mudskippers breathe through their wet skin when out of water, much as a frog does, and through air held in their gill chambers, which is why they must stay damp and never stray far from the mud.

Which marsupial has fingerprints so like a human's that they could confuse a crime scene?

Koalas have ridged fingerprints almost indistinguishable from ours, even under a microscope; a marsupial and a primate evolved the same pads separately, probably because both grip and climb.

Which animal has bright blue blood because it carries oxygen with a copper-based protein?

Horseshoe crab blood is blue because it carries oxygen with copper-based hemocyanin; it also clots on contact with bacterial toxins, so the crabs are caught and bled each year to safety-test vaccines and injectable drugs.

What is the longest-living vertebrate on Earth?

The Greenland shark is the longest-lived vertebrate known: radiocarbon dating of eye-lens proteins put one female at roughly 400 years old; they grow less than a centimetre a year and may not breed until about 150.

Which insect skips the pupal stage, hatching as a wingless miniature of the adult?

Grasshoppers undergo incomplete metamorphosis: the young 'hopper' moults several times, looking more like the adult after each one, and never forms a pupa as butterflies, ladybirds and ants do.

Which bird can fly backwards?

Hummingbirds can fly backwards: their wings beat dozens of times a second and rotate at the shoulder, giving helicopter-like control in any direction, including in reverse.

What is the traditional collective noun for a group of crows?

A group of crows is a 'murder', a term from lists of hunting words drawn up in the late 1400s, which also gave larks their 'exaltation'; bird scientists simply call any group a flock.

What nickname has Turritopsis dohrnii earned by turning from adult back into a juvenile, potentially again and again?

Turritopsis dohrnii is the 'immortal jellyfish': stressed or injured adults collapse into a blob and regrow as a polyp colony, in effect starting life over, though in the wild most still end up eaten.

What do Shark Bay bottlenose dolphins wear on their snouts while rooting on the seabed?

Shark Bay dolphins wear a marine sponge on the snout to protect it while rooting in the seabed; 'sponging' is a learned tradition, handed down almost entirely from mother to daughter.

Which animal is believed to be the world's most trafficked wild mammal?

The pangolin is thought to be the most trafficked wild mammal: more than a million were poached in a decade for their meat and their scales, which are only keratin, the stuff of fingernails.

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

Clownfish groups have a strict size-based pecking order: when the female dies the breeding male becomes female and the biggest non-breeder steps up as the new male, which makes Finding Nemo's plot biologically awkward.

What does the red 'blood sweat' that hippos ooze actually do?

Hippo 'blood sweat' acts as a sunscreen: it comes out colourless and turns red-orange within minutes, and its two acidic pigments absorb ultraviolet light and inhibit bacteria on the skin.

What is the term for animals that are most active at dawn and dusk?

Crepuscular animals keep twilight hours: dawn specialists are called matutinal and dusk ones vespertine, and some animals loosely called nocturnal, the house cat among them, are really crepuscular.

Which animal can rotate its head nearly 270 degrees in each direction?

An owl's eyes are fixed tubes that cannot swivel, so 14 neck vertebrae and slack, reservoir-lined arteries let the head turn about 270 degrees each way instead.

Which burrowing Australian marsupial leaves distinctive cube-shaped droppings to mark its territory?

Wombat droppings are thought to be cubes so that they stack and don't roll away, and working out how the gut shapes them won an Ig Nobel Prize in 2019.

Which Arctic predator has black skin hidden beneath fur that is actually transparent, not white?

Polar bear fur only appears white because its pigment-free hairs scatter light, and the guard hairs are hollow too, which helps the animal trap heat and float.

In which fish does the male carry the eggs in a brood pouch and release the fully formed young?

Seahorse females place up to 1,500 eggs in the male's pouch, and he carries them for anything from 9 to 45 days before the tiny young swim out.

What do a camel's humps actually store, despite the common myth that they hold water?

Fat fills the humps, giving a camel a reserve of calories to draw on when food runs short on a long desert crossing.

Despite their name, fireflies are not flies at all; they belong to which group of insects?

Beetles of the family Lampyridae number more than 2,400 species, and many of them flash their light as a signal to attract mates.

Which tree-dwelling mammal of Central and South America climbs down about once a week to defecate?

Sloth fur is a small ecosystem of its own: green algae grow in its grooved hairs, tinting the coat and helping to hide the animal among the leaves.

Which Arctic animal, long linked to unicorn legends, has a spiral tusk that is really an overgrown tooth?

Narwhal tusks are the male's left canine, growing up to three metres long, and medieval Europeans believed they were the horns of unicorns.

Which popular household pet cannot taste sweetness because of a mutation in a taste receptor gene?

Cat taste buds cannot bind sugary molecules, a quirk shared with their wild relatives, and savoury umami seems to matter to them the way sweetness does to people.

Which is the only deer species in which females, as well as males, normally grow antlers?

Reindeer bulls start growing antlers in March or April and cows a couple of months later, though the share of females that carry them varies from herd to herd.

Laika, the first animal to orbit the Earth aboard Sputnik 2, was which kind of animal?

Laika was a stray dog picked up from the streets of Moscow, and she died of overheating only hours into the flight.

Which bird is notorious for laying its eggs in other species' nests and leaving them to raise its chick?

Cuckoo trickery gave English the word 'cuckold', yet most species in the family actually build their own nests and raise their own young.

Which bear lives almost entirely on bamboo despite having the digestive system of a meat-eater?

Giant panda meals are about 99% bamboo, yet with a carnivore's gut and genes the animal gets little energy and little protein out of it.

Which fish, served in Japan as the delicacy fugu, carries a potentially lethal toxin in its liver and skin?

Pufferfish may be served only by specially trained chefs, though Japan now farms some on a controlled diet that leaves the whole fish free of poison.

Which orange-and-black butterfly migrates thousands of miles from Canada to overwinter in Mexico?

Monarch migration is a relay: no single butterfly makes the whole round trip, and it takes several generations to work back north in spring.

Which insect performs a figure-eight 'waggle dance' to tell its nestmates the direction and distance of food?

Honey bee foragers angle each waggle run to match the food's bearing from the sun, a code first translated by the Nobel laureate Karl von Frisch.

Which Swedish naturalist formalised the two-part Latin names, such as Homo sapiens, used for every species?

Carl Linnaeus, known as the father of modern taxonomy, first published his Systema Naturae in 1735 while living in the Netherlands.

Which spiny, ant-eating mammal of Australia and New Guinea lays eggs instead of giving birth to live young?

Echidna species number four, and despite the nickname spiny anteater they are not closely related to the true anteaters or to hedgehogs.

Which predator of estuaries and coasts from India to northern Australia is the largest living reptile?

Saltwater crocodile males can reach 6 metres and more than a tonne, and the species has the strongest bite of any living animal.

Which Pacific archipelago, studied by Charles Darwin in the 1830s, helped inspire his theory of evolution?

Galápagos Islands wildlife gave the place its very name: galápagos is a Spanish word for the giant tortoises that live there.

What name is given to the biological sonar that dolphins and porpoises use to find prey in murky water?

Echolocation works by sending out a focused beam of high-frequency clicks in whichever direction the animal's head is pointing, then reading the echoes.

Which amphibian, native to lakes in the Valley of Mexico, can regrow lost limbs and even parts of its brain?

Axolotl DNA runs to 32 billion base pairs, the largest animal genome sequenced when it was published in 2018, and it is being searched for the secret of limb regrowth.

Which mammal of the Americas has a nine-banded species whose young are born as identical quadruplets?

Armadillo litters of this species start as one fertilised egg that splits into four identical embryos, and a frightened adult can leap about a metre straight up.

Which spotted predator, the only Panthera species native to the Americas, kills by biting through the skull?

Jaguar jaws are powerful enough to pierce the shells of turtles and tortoises, and the killing bite is aimed between the ears of its prey.

Which carnivorous marsupial is threatened by a contagious facial cancer passed on through bites?

Tasmanian devil jaws have the most powerful bite for body size of any living mammalian carnivore, strong enough to cut through thick metal wire.

Which sea creature can push its stomach out through its mouth and into a clam's shell to feed?

Starfish need a gap of only a fraction of a millimetre between the two halves of the shell to get the stomach inside.

Which noisy insects of eastern North America emerge from the ground in vast broods only every 13 or 17 years?

Cicadas may keep to prime-numbered cycles because predators with shorter breeding cycles can then rarely fall into step with an emergence.

Rhinoceros horn is made of which protein?

Keratin makes a rhino's horn grow much as a fingernail does, and there is no good evidence that it has any of the health benefits claimed for it.

Which migratory bird never settles on the ground by choice and can fly for ten months without landing?

Common swift legs are so short that they serve mainly for clinging to walls; away from the nest the bird drinks, feeds and often mates and sleeps on the wing.

Which lizards can climb smooth walls and even cross ceilings thanks to specialised adhesive toe pads?

Geckos mostly lack eyelids too, so they lick the clear membrane covering each eye to keep it clean and moist.

Which semi-aquatic South American mammal is the largest living rodent?

Capybara feet are slightly webbed, and the animal can hold its breath underwater for up to five minutes at a time.

Which South American fish, a knifefish despite its name, stuns prey with shocks of up to 860 volts?

Electric eel studies in the 1770s helped lead to the invention of the battery in 1800, and the fish has to keep surfacing because it breathes air.

Which flightless bird of Mauritius was wiped out within a century of Dutch sailors first recording it in 1598?

Dodo relatives are still flying: the bird belonged to the same family as doves, and it owes much of its fame to a part in Alice's Adventures in Wonderland.

Spiders, ticks and mites all belong to which class of arthropods, whose adults almost all have eight legs?

Arachnids share their name with Arachne, the boastful weaver of Greek myth who was turned into a spider.

Which venomous eight-legged predators glow a vivid blue-green when ultraviolet light is shone on them?

Scorpions glow so reliably that a hand-held ultraviolet lamp has long been the standard tool for finding them on night-time field surveys.

The Great Barrier Reef, the biggest single structure made by living things, was built by which tiny animals?

Corals in their billions, each one a tiny soft-bodied animal, built a reef so large that it can be seen from outer space.

Which Australian songbird has been recorded imitating chainsaws, car alarms and camera shutters?

Lyrebird song is mostly borrowed from other birds, though, and how often it really copies human-made noise is exaggerated.

What is the collective noun for a group of geese on the ground, as opposed to a flock in flight?

Gaggle applies only on the ground: in the air the same birds become a skein, a team or a wedge, and a plump when they fly close together.

In which deep-sea fish does the much smaller male attach to the female, sometimes fusing with her body?

Anglerfish are named for their fishing rod, a modified fin ray whose tip glows in the deep-sea species thanks to bioluminescent bacteria living inside it.

Which fish, thought extinct for 66 million years, turned up alive in a fisherman's catch in 1938?

Coelacanth number one was spotted by the museum curator Marjorie Courtenay-Latimer, and the living genus, Latimeria, is named after her.

Which snake of South and Southeast Asia, measured at more than 6 metres in the wild, is the world's longest?

Reticulated python records top the length table, but the species is only the third heaviest snake, behind the green anaconda and the Burmese python.

Which slow-moving lizard of the American Southwest has venom that gave rise to drugs for type 2 diabetes?

Gila monster venom contains exendin-4, the peptide copied to make exenatide, the first GLP-1 drug for diabetes, and the animal is the only venomous lizard native to the United States.

What is the term for the summer dormancy that some land snails enter to survive periods of heat and drought?

Aestivation takes its name from aestas, the Latin for summer, and it is a light sleep that the animal can snap out of quickly.

Which nocturnal, ground-dwelling bird of New Zealand is the world's only flightless parrot, and its heaviest?

Kakapo breeding is unique among parrots too: the males gather at display grounds, known as leks, to compete for the attention of females.

Which North American bird, once counted in billions, became extinct when Martha died at a zoo in 1914?

Passenger pigeon flocks were so vast that one seen over Ontario in 1866 was said to have taken 14 hours to pass overhead.

Which lizard-like New Zealand reptile is the sole survivor of an order that thrived in the age of dinosaurs?

Tuatara hatchlings have a visible 'third eye' on top of the head, more pronounced in this species than in any other living four-limbed animal.

What term describes a harmless animal, such as a hoverfly, evolving to look like a dangerous one?

Mimicry of this bluffing kind is called Batesian in honour of the naturalist who described it; when harmful species copy one another instead, it is Müllerian.

What term describes a partnership, like that of cleaner fish and their clients, in which both species benefit?

Mutualism can begin lopsidedly: some such partnerships are thought to have evolved from parasitism, in which only one side gains.

Which wading bird makes the longest known non-stop flight, crossing the Pacific from Alaska to New Zealand?

Bar-tailed godwit migrants shrink their own digestive organs before departure to carry more fuel, and one tagged bird flew 13,000 km without landing.

Which primate of Madagascar taps on tree trunks and hooks out grubs with a long, thin middle finger?

Aye-aye front teeth never stop growing, which led early naturalists to classify the animal as a rodent, and even as a kind of squirrel.

Which cephalopod with a coiled, chambered shell has barely changed in hundreds of millions of years?

Nautilus species are the last living members of their subclass, which parted long ago from the line leading to every other living cephalopod.