Blog topic
Animals & Nature articles
How birds navigate, why bees make honey, how camouflage and venom work, how whales talk and fish breathe. Most of these pieces start with a question a child would ask and end with the mechanism biologists actually found, which is usually stranger than the guess.
29 explainers, newest first. Each one ends with real questions from the unit that teaches it, so you can read the explanation and then check whether it stuck.
These are the readable companion to the Animals & Nature track, which holds 18 units and 2,028 practice questions. If you are starting the subject rather than looking something up, the study guide is the better place to begin.
How Do Snakes Move? Four Gaits Without a Single Leg
A snake has no legs and can outpace a person, climb a tree, cross loose sand and swim. The four ways it moves, and the scales and muscles that make them work.
September 15, 20265 min readWhat Is Plankton? The Drifting Life That Makes Half the World's Oxygen
Plankton is every organism that drifts in water rather than swimming against it, from bacteria to jellyfish. Why it feeds the ocean and what it does to the air.
September 15, 20264 min readWhy Are Frogs Disappearing? A Fungus, a Trade and the Animals That Breathe Through Their Skin
Amphibians are vanishing faster than any other group of animals, with two fifths of species threatened. The fungus behind it, and what is being tried.
September 15, 20264 min readHow Do Elephants Communicate? Rumbles Below Hearing, Feet That Listen and Names
Elephants talk in rumbles too low for people to hear, felt through the ground kilometres away, and they appear to use names. What the calls carry.
September 15, 20264 min readHow Do Sharks Sense Their Prey? Smell, Electricity and a Line Along the Body
Sharks find prey with senses humans lack, including detectors of the electric fields all animals give off. How each sense works, and what the myths got wrong.
September 15, 20265 min readWhat Was the Dodo? An Extinction Within a Century of Discovery
The dodo was a large flightless pigeon on Mauritius that sailors first saw in 1598 and last saw about 1662. Why it could not survive people.
September 15, 20265 min readHow Do Bees Communicate? The Waggle Dance Explained
A honeybee that finds flowers tells the hive where they are with a dance. How the waggle code works, how it was cracked, and what else bees say.
September 14, 20265 min readHow Do Salmon Find Their Way Home? Smell, Magnetism and Memory
After years at sea, a salmon returns to the stream it hatched in. The magnetic map to the coast, the smell that leads upriver, and why it bothers.
September 14, 20264 min readWhy Do Birds Sing? Territory, Mates and a Learned Skill
Birdsong claims ground, attracts a mate and, in songbirds, has to be learned from adults like a language.
September 14, 20265 min readHow Do Animals See Colour? Dogs, Bees, Birds and the Mantis Shrimp
Colour vision depends on how many kinds of light-sensing cell an eye has. Why dogs see fewer colours than we do, why birds and bees see more.
September 14, 20264 min readWhy Do Zebras Have Stripes? Four Theories and the Experiments That Tested Them
Zebra stripes have been explained as camouflage, confusion, cooling and fly repellent. What each theory predicts, and why the biting-fly explanation has won.
September 14, 20264 min readHow Does an Octopus Change Colour? Skin That Thinks for Itself
An octopus can match a rock in under a second without seeing colour. The pigment sacs in its skin, the nerves that drive them, and the puzzle of how it chooses.
September 14, 20264 min readHow Does a Caterpillar Become a Butterfly? What Happens Inside the Chrysalis
A caterpillar does not sprout wings; it dissolves most of itself and rebuilds from cells it carried since the egg. The stages, the hormones and what survives.
September 14, 20264 min readHow Do Wolf Packs Work? The Family Behind the Myth of the Alpha
A wolf pack is a family, two parents and their young, not a hierarchy won by fighting. Where the alpha idea came from, and how packs really hunt.
September 14, 20264 min readHow Do Penguins Survive the Antarctic Winter? Feathers, Fat and the Huddle
Emperor penguins breed in the coldest winter on Earth, the males fasting on the ice for two months. The insulation, the huddle and the physiology behind it.
September 14, 20265 min readHow Echolocation Works: Seeing With Sound
Bats, dolphins and a few blind humans build a picture of the world from echoes. The physics of the calls, how the brain reads them, and the moths that jam them.
September 9, 20264 min readWhy Do Cats Purr? What the Sound Means and How It Is Made
Cats purr when content, but also when injured, frightened or giving birth. How the sound is produced, what it signals, and the evidence on whether it heals.
September 9, 20264 min readHow Do Birds Know Where to Migrate?
The sun, the stars, Earth's magnetic field and inherited instinct all play a part in one of nature's great feats.
August 28, 20266 min readHow Does Camouflage Work in Animals?
The main strategies, from blending in to disruptive patterns and mimicry, and how some species change colour at will.
August 28, 20266 min readWhy Do Bees Make Honey?
Why do bees make honey? It is winter food storage, not a gift. Here is how nectar becomes honey and why the process makes it last almost forever.
August 28, 20265 min readWhat Is Hibernation?
How animals survive winter by slowing their bodies almost to a stop, and why bears are not textbook hibernators.
August 28, 20266 min readHow Do Whales Communicate?
Songs, clicks and calls that travel for hundreds of kilometres, and what researchers have worked out about their meaning.
August 28, 20266 min readWhy Are Some Animals Venomous?
The difference between venom and poison, what venom actually does to a body, and why it evolved so many times.
August 28, 20265 min readHow Do Spiders Make Webs?
Where silk comes from, how an orb web is built step by step, and why spiders do not stick to their own threads.
August 28, 20266 min readWhat Is an Apex Predator?
What sits at the top of a food chain, why removing one can reshape an entire ecosystem, and the famous wolf example.
August 28, 20266 min readHow Do Fish Breathe Underwater?
How gills pull oxygen from water, why the countercurrent system is so efficient, and how some fish breathe air.
August 28, 20265 min readWhy Do Leaves Change Colour in Autumn?
The pigments that were always there, why trees shut leaves down, and what makes some years more spectacular.
August 28, 20265 min readWhat Is a Keystone Species?
Why some animals matter far more than their numbers suggest, with the sea otter and beaver examples explained.
August 28, 20266 min readHow Do Ant Colonies Organise Themselves?
How do ant colonies organise themselves without a leader? Chemical trails, simple rules and the surprising truth about what the queen actually does.
August 28, 20266 min read