Cannibalism is the act of eating one’s own species. So this can apply to any species from humans to mammals to insects. While this may sound gruesome, there are plenty of reasons why cannibalistic animals exist. The reason they are driven to eat members of their own species are typically linked to survival, but can still be quite surprising to learn about. This article will cover 14 cannibalistic animals and explain why they’ve chosen to engage in this act.
14 cannibalistic animals
Here is a list of 14 animals that participate in cannibalism. While some you might have heard about, there may be a few on this list that comes as a surprise.
Scientific subfamily: Cricetinae
Yes, these cute popular pets are known to eat each other! Scientists have found that a restricted diet of all-corn can cause cannibalism in hamsters. So to avoid mothers from eating their young, it’s best to feed your hamsters a varied diet of roots, grains, and insects.
Interestingly enough, hamsters have also been observed killing and eating each other for space and territory reasons. Mothers will eat their young if she feels there are too many babies to take care of in a limited space, especially if they are weak or sick. This increases the chances of the other, stronger babies surviving.
2. North American red squirrels
Scientific name: Tamiasciurus hudsonicus
When it comes to red squirrels, males will often kill and eat nearby pups that were fathered by other red squirrels. Different from other species on this list, this act of cannibalism occurs even when there is plenty of food available. Theories explaining why are linked to female squirrels’ having multiple partners and second litters during years with abundant food. So, to ensure the second litter only perpetuates his genes, the male will kill off the pups in the first litter.
3. Tiger salamanders
Scientific name: Ambystoma tigrinum
Tiger salamanders start eating each other young, at around 4 weeks old. This occurs when some morph to have wider heads and bigger teeth, making it easy to eat other salamanders. The teeth of these cannibalistic tiger salamanders can grow three times bigger than their siblings! They eat each other to stay fed and to keep their population low enough so they won’t have any food shortage issues.
Scientific name: Pan troglodytes
Chimpanzees may be a close relative to humans, however, they don’t necessarily treat their young the same way we do. Biologists have observed these great apes eating their young for various reasons, including for nutrition, survival, dominance issues, and to prevent overcrowding.
5. African pygmy hedgehogs
Scientific name: Atelerix albiventris
Another popular pet on this list that will cannibalize their young is the African pygmy hedgehog. These animals look cute, but when the mother feels frightened, they will eat their newborn. It’s best to stay away from your birthing pet to keep her calm and separate the young after birth.
6. Sand tiger shark
Scientific name: Carcharias taurus
The highly unique species on this list is the sand tiger shark, where cannabilism occurs before they are even born. While many shark species have embryos that eat unfertilized eggs, the largest embryo of a sand tiger shark will eat all smaller developed embryos!
This biggest embryo will consume all its potential siblings until it’s the last one standing. Scientists believe it’s a process towards producing the strongest offspring as well as increasing the baby’s size, so they have a higher chance of surviving after born.
7. European praying mantis
Scientific name: Mantis religiosa
The praying mantis female can be extremely aggressive during the mating ritual. Males will often play dead to avoid being eaten since the female is known to tear off the male’s head and eat it. She does this after mating to provide nourishment for herself so she can produce healthy offspring.
Researchers have some evidence to show that the females can lay more eggs when they eat their partner. This doesn’t happen all the time however, any may be linked to how healthy or starved the female is at the time of mating. For reasons unknown, sometimes the male will eat the female after mating.
Scientific family: Coccinellidae
Identifiable by their red color and dark spots, ladybugs aren’t only a pest control species that kill aphids, rootworms, and other insects. These beetles also eat other unhatched members of their own species. It has been proven that larvae eating their unhatched siblings develop faster than the non-cannibalistic larvae.
9. Crab spider
Scientific family: Thomisidae
The crab spider displays a backward case of cannibalism where it’s not the parent eating the offspring. Instead, the mother will give her newly hatched young unfertilized eggs and her own body to eat so she can ensure their survival.
10. Black widow spider
Scientific genus: Latrodectus
While a widow generally refers to a female that has lost her partner due to death, the black widow spider is typically the one doing the killing. These spiders will consume the male moments after mating, possibly to nourish herself and the 500 or more babies she will rear. Sometimes females will eat her own babies after they hatch, and newly hatched spiders are known to eat their siblings.
Scientific order: Scorpiones
Scorpions are generally very protective of their young, even carrying them around on their backs. However, they can also resort to cannibalism when there isn’t enough food to go around. Since scorpions have around 100 young at a time, the mother will sometimes sacrifice a few of her own as food to survive.
Scientific genus: Perca
Perch are fish that live in groups in various waters around the world, depending on the species. They are known to be invasive species and aggressive, sometimes biting the cameras of underwater photographers. These fish also engage in cannibalism, where they eat their species from different groups. However, sometimes parents or siblings will even eat their younger relatives.
Scientific name: Hippopotamus amphibius
What’s probably most surprising about cannibalistic hippos is the fact that these animals are herbivores. Meaning they naturally only feed on plants. These large animals need around 88 pounds of grass each day to survive, so during times of drought and food scarcity, they resort to getting nutrients wherever they can, including each other.
A rare moment of a hippo eating the carcass of another hippo has been seen in South Africa’s Kruger National Park.
14. Polar bear
Scientific name: Ursus maritimus
While the white polar bear from the Arctic typically wouldn’t be on this list, they have shown signs of cannibalism in recent years. Most people believe that climate change has reduced ice blocks they can hunt seals from, forcing them to eat each other to survive. They have been photographed eating smaller members of their own when food resources are scarce.