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ScienceReptiles Grr

A gecko holds on with physics, not glue

A gecko can hang from a pane of glass by one toe — and there isn't a drop of glue involved.

Look closely at the underside of those feet and you'll see ridges, like fingerprints. Each ridge is covered in millions of microscopic hairs called setae, and each seta splits again into…

ScienceBirds Grr

Your budgie sees a colour you don't — and it glows

Hold a budgie under a UV lamp and parts of its face light up like a highlighter. The yellow feathers on the crown and cheeks fluoresce — they absorb ultraviolet light and throw it back as a glow.

To us, that's a party trick. To another budgie, it's part of the picture. Birds hav…

ScienceReptiles Grr

Your tortoise can't leave its shell — it's wearing its own spine

A tortoise doesn't live in its shell the way a hermit crab lives in a borrowed one. It can't climb out. The shell is part of its skeleton.

Over evolutionary time, the ribs and vertebrae of early turtles flattened and fused into a bony dome, with the shoulder blades ending up ins…

ScienceFarm animals Grr

Pigs learned to play video games — with a joystick

Scientists handed a pig a joystick, and the pig played.

The work began decades ago at an American agricultural university, where researchers wanted to know how much a pig could really understand. They modified an arcade-style setup: snout on the joystick, cursor on the screen, h…

ScienceSmall rodents Grr

Scientists tickled rats — and found laughter

A neuroscientist spent years tickling rats in a lab, and the rats kept coming back for more.

In the 1990s, Jaak Panksepp noticed that young rats at play made a particular chirp at around 50 kilohertz — far above human hearing. When he tickled them, especially on the nape and bel…

ScienceRabbits Grr

Your rabbit can't see the treat under its nose

Hold a piece of parsley right in front of your rabbit's face and watch it fumble. Not because it's clumsy — because that exact spot is invisible.

Rabbit eyes sit high on the sides of the skull, giving a field of view close to all the way around. Brilliant for spotting a buzzard.…

ScienceReptiles Grr

Your bearded dragon has a third eye — and it's watching the ceiling

Look closely at the top of a bearded dragon's head, between the eyes and slightly back. There's a small pale scale, a little like a freckle. That's a parietal eye — a genuine third eye, wired to the brain.

It doesn't form pictures. No lens worth speaking of, no colour, no detail…

ScienceBirds Grr

The parrot who asked what colour he was

A grey parrot once looked in a mirror and asked a question nobody had taught him: what colour am I?

His name was Alex, bought from a pet shop in the late 1970s by the scientist Irene Pepperberg. At the time, most researchers assumed birds could only mimic. Pepperberg spent three…

ScienceHorses Grr

Your horse sleeps standing up — but not the sleep that counts

A horse can doze on its feet without falling over. Tendons and ligaments in the legs lock the joints into place — the stay apparatus — so the body rests while the frame holds itself up. It costs almost no effort.

It's a prey animal's bargain: stay upright, stay ready to run.

Bu…

ScienceFish Grr

Your goldfish hears you — with its swim bladder

The goldfish in the corner of your living room is listening. Not metaphorically. It has a better sense of hearing than most fish in the sea.

Goldfish, carp, tetras, catfish and their relatives share an unusual piece of anatomy: a chain of tiny bones linking the swim bladder to t…

ScienceRabbits Grr

A rabbit cannot be sick — and that changes everything

Your rabbit will never throw up. Not from a bad meal, not from a swallowed clump of fur, not ever.

The anatomy is simply built the other way. A rabbit's stomach sits behind a powerful one-way valve, and the muscular reflex that lets dogs, cats and people vomit just isn't there.…

ScienceFerrets Grr

The jill who cannot stop waiting

A female ferret can, quite literally, die of waiting.

Ferrets are induced ovulators. A jill releases eggs only in response to mating. Come into season in spring, with no male and no veterinary intervention, and she simply stays in season — sometimes for months, oestrogen high th…

ScienceBirds Grr

The canary that rewrote neuroscience

For most of the 20th century, scientists were sure of one thing: the adult brain does not make new neurons. You get what you're born with, and after that it's downhill.

Then researchers started looking closely at canaries.

Male canaries learn and revise their songs, and the bra…

ScienceCats Grr

Your cat cannot taste sweetness — and never could

Offer a cat a spoonful of ice cream and it may well lick it. But not for the sugar. Cats are the one group of mammals known to be effectively blind to sweet taste.

The reason sits in their DNA. Sweet taste in mammals depends on a receptor built from two proteins. In cats, the ge…

ScienceRabbits Grr

Your rabbit eats dinner twice — and you've likely never seen it

Somewhere around dawn, while you were asleep, your rabbit ate a meal you have never served.

Rabbits are hindgut fermenters. Grass and hay are tough stuff, so the fibre is sorted in the gut: the indigestible bits become the round, dry pellets you sweep up, while finer material is…

ScienceBirds Grr

Your budgie sees a colour you never will

Hold a budgie under a UV lamp and parts of it glow. The yellow feathers on the crown and cheeks fluoresce — a soft, lantern-like shine that is completely invisible to us.

Budgies, like many birds, have four types of colour-sensing cone in the eye instead of our three. The extra…

ScienceFarm animals Grr

The goat in your garden has panoramic vision — literally

Look a goat in the eye and something odd looks back: the pupil isn't round, it's a horizontal slot, like a letterbox.

Sheep have them too. So do horses, cattle and deer. It isn't decoration. That wide slit lets in light from a very broad strip of the world, giving grazing animal…