The Hedgehog
Quite possibly the oldest living mammal on Earth.
By: Kirsten Brooker | May 29, 2025 | 809 Words

(Photo by Boston Herald/MediaNews Group/Boston Herald via Getty Images)
You have likely heard of Sonic the Hedgehog. You know, the little blue guy that collects coins and travels through different worlds? Well, the mammal is equally as interesting as the Sonic video game is fun. Known for their spiky spines that replace fur on the animal, hedgehogs are believed to be the oldest living mammals on Earth.
Ancestry and Evolution
Scientists believe that the hedgehog has roamed the Earth for more than 15 million years. A now-extinct species of hedgehog, the Mediterranean, was the size of a pig. Their spiky outer covering and their highly sensitive sense of smell could be why the mammal has survived for so long.
There are at least 17 species of hedgehog worldwide, primarily located in Europe, Asia, Africa, and New Zealand. They share distant ancestry with shrews (mole-like animals in the Soricidae family). Because of their pokey fur, they have few predators, so the animals are commonly considered to be an invasive species and troublesome pests.
In Asian and European folklore, hedgehogs are associated with intelligence and wisdom. In Africa, they are regarded as magical creatures.
Appearance
The animals are not large – typically only about one to four pounds. They have cone-shaped heads and short legs. The rest of their body is equipped with thousands of quills that act as a defense mechanism against predators. Touching the quills can cause pain. Oddly, this feature does not relate them to porcupines as one might think. Much like in the video game, hedgehogs will curl up into a little ball when they sense danger or are under attack.
Diet and Habitat
Hedgehogs are omnivorous, meaning they eat both plants and other animals or insects. As nocturnal animals, they do all their eating at night. They consume fruits that have fallen to the forest floor and nearly any invertebrate they can catch (frogs, rodents, carrion, baby birds, and eggs).
A strange fact about hedgehogs is that they are lactose intolerant, which means they cannot drink milk. For those in the wild, that is not a big deal. However, for domesticated hedgehogs, it is essential to provide them the right food. Many pet stores carry food specifically designed for hedgehogs.
While they spend their nights out and about foraging for food, hedgehogs spend their days at home. They prefer to build their nests in extremely wet and dense pine forests. They are mostly found in Britain and dwell on the edges of woodlands. They are also found in upland areas on mountainsides. Though they do not naturally exist in the wild in the United States, the hedgehog population there has grown due to the domestication of the animal.
Reproduction and Lifespan
There is not a particular time of year for hedgehogs to breed. They spend most of their lives alone until it is time to find a mate and have babies. When that time comes, a male hedgehog will put on quite a show for the female, snorting, puffing, and dancing in a rhythm.
Up to 11 babies can be in one litter, even though because of their natural roundness, it can be difficult to tell when a female is pregnant. Baby hedgehogs are known as hoglets. Each hoglet will stay with its mother until it reaches about four to seven weeks of age. It is important to not interfere with a hedgehog’s nest as the mother can sense a change in smell and potentially eat the babies if she feels threatened. Though some can live up to seven years old, the typical lifespan of a hedgehog is between two and five years.
Hedgehog Predators
The list of predators who hunt hedgehogs is rather short. Apparently, a mouthful of sharp spines is not a favored menu item. However, the spiny creatures do watch out for a few animals. The most concerning is humans. Deforestation of their habitats is the leading cause of the decline of the species. After humans come owls, wild dogs, mongooses, and mustelids that are predatory threats to the mammal. Foxes and wolves also will try to make a meal out of a hedgehog.
Interesting Things to Note About a Hedgehog
- They are great for reducing irritating insects and pests in your home and garden. That is why they are often kept and trained as pets.
- Be sure to check the rules in your area because they are illegal to own in many US states.
- They eat only at night.
- They will hibernate anywhere in the vicinity where they live.
- They will change their scent to something they prefer by licking the scent and then licking their quills.
- Hedgehogs are believed to be the oldest living mammals on Earth.
- The animals are not large – typically only about one to four pounds.
- There are at least 17 species of hedgehog worldwide, primarily located in Europe, Asia, Africa, and New Zealand.