Spiky scales
There are many ways to protect yourself from being eaten. Animals can be poisonous, taste disgusting, look dangerous or be camouflaged so as not to be visible. Some animals have developed a protective covering of sharp skin flaps or spines and thorns, making them difficult or dangerous to put in the mouth.
The thorny devil's body is covered in sharp, scary thorns.
Photo: Annette-Teng-CC-BY
The spiny-tailed lizard rolls itself to a spiky ball when it feels threatened.
Photo: Daniel-Heuclin-naturepl.com
The thorny devil looks more dangerous than it is
The thorny devil is a lizard that has its upper body covered in hard, spiny skin flaps. The thorny body makes it difficult for predators to eat it. In addition, it is sand-coloured and difficult to spot. The thorny devil is native to Australia. It looks dangerous, and can inflate itself to look bigger. But it’s really only dangerous to ants. It can eat thousands of ants in a day.
The thorny devil is long-lived and can live for over 20 years. That’s not bad for a creature that inhabits the desert. Another thorny lizard is the East African spiny-tailed lizard. Like the thorny devil, it lives in desert areas, but in Africa and Madagascar. There are 40 different species and they can grow from 20 to 70 centimetres in length.
The hedgehog uses its spines as a defense.
Photo: I-Jorg-Hempel-CC-BY-SA
Close-up of the hedgehog's spines.
Photo: BS-Thurner-Hof-CC-BY-SA
The hedgehog's spines keeps many predators away, but the Eurasian eagle-owl doesn't get intimidated.
Photo: Piotr_J-CC-BY-SA
A spiny celebrity
The spiny hedgehog is familiar to most people. Hedgehogs are found in Europe, Asia and Africa in 15 different species. In Sweden, the hedgehog is found everywhere except in the far north. It is common in our gardens and also thrives in city parks. The spines of the hedgehog are actually hairs – developed through evolution into sharp spines. If the hedgehog feels threatened, it curls up and erects its spines. An adult hedgehog can have up to 7,500 spines. The spines protect them from being eaten. But foxes, martens and birds of prey all feed on hedgehogs. The hedgehog itself usually eats insects and worms, but it also likes to eat pancakes or dog food that people place in their gardens.
The African crested porcupine also uses its spines as a defense, just like...
Photo: Von-Drew-Avery-CC-BY
...the North American porcupine.
Spiny rodents
Another animal that uses spines for protection is the porcupine. The porcupine is a rodent larger than hedgehogs and is found in southern Europe and Africa. They can reach lengths of up to 70 centimetres and weigh as much as 30 kilograms. In South America and Mexico, the New World porcupines are a spiny relative of the guinea pig. They use their tails to climb trees where they look for food in the winter.