10 Cruelest Animals in the World

Written by Kyle Glatz
Published: September 18, 2022
Image Credit iStock.com/Rainbohm
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When we watch programs about lions hunting baby zebras in the savannahs of Africa, the narrator often mentions how cruel the world can be. In one sense, yes, the lion is cruel since it’s killing a young creature. Then again, that’s often the alternative to starvation for these animals. Any way we slice it, survival often comes at the cost of others in this world, and some animals take advantage of that more than others. So, what are the cruelest animals in the world?

We’ll show you 10 different creatures that count for being the cruelest ones around! First, though, we have to determine what earns an animal a spot on this list.

What Qualifies One as Part of the Cruelest Animals in the World?

Although we could just populate this list with the deadliest animals, they’re not always trying to be cruel. Sometimes, they’re just trying to eat and survive. Instead, we are looking for animals that demonstrate an extraordinary level of cruelty.

We’re listing animals that are mean and harmful to others, and they may actually like it. You may think that quality is hard to find in the animal world, and you’d be mostly right. However, as we go through this list of the cruelest animals in the world, you’ll clearly see that some of these creatures are truly unpleasant.  

10. Cats

Egyptian Mau cat lying on the ground
Cats kill a number of animals for entertainment.

iStock.com/Tbowerman

No, we don’t mean lions, panthers, and cougars. We’re talking about the domestic animals that might be sitting on your lap as you read this. One of the cruelest things a creature can do is to take a life without needing to, right?

Domestic cats kill in huge numbers, upwards of 4 billion birds and 22 billion mammals around the world each year. While they certainly eat some of these creatures, they just catch and kill many of them. Those are the ones that your cat will leave on your kitchen floor in the morning. So, cats are one of the cruelest animals in the world because they kill vast numbers of animals for fun and entertainment.

By the way, if your cat was larger, it would almost certainly try to eat you.

9. Dolphins

dolphin smiling at the camera
Dolphins predate on their young so the female can get pregnant soon.

Although movies like Flipper endeared us to these creatures, dolphins aren’t all that kind. They are smart, though, so they know how to use violence as a tool for feeding or to pass the time.

Dolphins kill each other’s young so the females can become pregnant sooner. Several males will coerce a single female into reproducing, too. Their intelligence also apparently breeds boredom as they’ll torture and play with their prey before consuming it. That may be a defense mechanism, but other times they’re just having fun.  

8. Wild Dogs

Wild Dog Breeds: Dhole
Wild dogs are cruel.

Nimit Virdi/Shutterstock.com

Unlike lions, wild dogs can’t snap the neck of a zebra or wildebeest with a bite. So, when they hunt other animals, they essentially wear them down and start eating them alive.

They don’t have time to go for the kill because a lion or another one of the big cats that live in the same area could swoop in and take their prey.  So, these animals are cruel because they need to be, not necessarily because they’re especially mean.  

7. Tarantula Hawks

tarantula hawk on a flower
Tarantula hawks hunt large spiders.

iStock.com/Thom_Morris

Some creatures’ behaviors are so callous that they make you take a step back and wonder what series of events in their evolution made them so horrible. One of them is the tarantula hawk. This animal’s existence relies on its ability to kill other animals.

Specifically, the tarantula hawk will hunt large spiders, like tarantulas, and then use its powerful sting to paralyze them. Sounds bad, right? Well, it gets a lot worse because the female wasp will then lay an egg in the creature’s body and then take it back to a burrow.

Once that egg hatches, the baby wasp emerges and eats the creature while it’s still alive. That is a rather horrible way to die. For that reason, tarantula hawks are some of the cruelest animals in the world.

6. Crocodiles

Heaviest Animals: Saltwater Crocodile
When given the chance, crocodiles can eat each other.

PomInOz/Shutterstock.com

Crocodiles are large creatures with small, poorly developed brains. They tend to lash out at whatever comes into their area, including humans. It’s estimated that over 1,000 humans meet their end at the jaws of crocodiles every year.

The thing that makes them cruel is their willingness to turn on each other. If food is scarce or a group of them is caught in a feeding frenzy, they will gladly death roll the limbs off other crocodiles. It’s not malice that makes them cruel, though. They simply cannot differentiate between something that means them no harm and prey.

5. American Nursery Web Spiders

american nursery web spider
Male American nursery web spiders will tie females’ legs during mating to avoid being eaten afterward.

SDeming/Shutterstock.com

The Pisaurina mira is called the American nursery web spider, and they engage in rather cruel behaviors toward one another. This behavior is sexual cannibalism. That means the female will eat the male after copulating. While this is somewhat beneficial to the next generation, it’s a cruel act because males must risk their lives to take part in something that they are biologically inclined towards.

Males do have a certain type of defense. They’ll try to tie the female’s legs with silk before the act to escape certain death.  

4. Chimpanzees

Aggressive Animal: Chimpanzee
Cannibalism is common in chimpanzee communities.

Afandi Teguh Afriyanto/Shutterstock.com

Chimpanzees are incredible creatures. They’re intelligent and powerful. Like humans, they apparently have an innate sense of fairness and exhibit altruism. That combination of intelligence and a desire for fairness also makes them one of the cruelest animals in the world.

In 2005, a man delivered a birthday cake to his former chimp pet at an animal sanctuary. Two other chimps that saw this cake delivered did not receive any, and they attacked the man. The details of the attack are horrible, and they show how cruel these creatures can be over an imagined slight.

Chimps also engage in violent raids on other members of their species and engage in cannibalism. They have even fought a primitive sort of war over many years, the Gombe Chimpanzee War. All in all, chimps have an incredible capacity for violence and cruelty.

3. Lions

In a pride takeover, lions often commit infanticide.

Petr Ganaj/Shutterstock.com

Lions are just as cruel and unforgiving as the world around them. They often kill young, weak, or pregnant animals to obtain a meal. They’ll even turn on another, too. Males will commit infanticide when they take over new territory, making way for their young to be born.

2. Meerkat

Meerkats kill each other for dominance.

Millie Bond – Copyright A-Z Animals

They may look like cute furry critters, but meerkats have a violent streak. In fact, a study from 2016 tried to unlock the phylogenetic roots of human violence. While studying violence in mammals, the researchers found that meerkats often kill one another.

Roughly 20 percent of all meerkat deaths come at the hands of other meerkats. They’ll fight and kill each other for dominance. They’ll even kill off their young to maintain a level of dominance in their faction. Meerkats are also not above eating one another!

Some researchers believe that their sentinels may purposely try to encourage other meerkats to look for danger outside of their bolt-holes when danger is present. That provides the lookout with a better chance to escape.

1. Humans

Human (Homo sapiens) - diverse group of humans
Humans can be very cruel.

Rawpixel.com/Shutterstock.com

Was there really any question about this one? Humans have a great capacity for kindness and empathy. However, when you look at some of the things that people have done in the name of hurting others, it’d be foolish not to include us on this list.

Comedian George Carlin once joked about how humans took extreme behaviors seen in other animals and pushed them to their limits. Humans have engaged in massive wars that kill millions of people and keep making deadlier, more efficient weapons to kill others.

Humans have even actively pursued genocide against groups of people just within the last century. We’ve even fine-tuned torturing other humans in despicable ways. Humans have also offered ritual human sacrifices in the hundreds of thousands. Humans simply adore violence against other humans.

That’s just what we do to one another, though. That doesn’t include what we do to other animals. And to put all this in perspective, we’re the most enlightened sentient beings on the planet. We could behave better, but we often let our cruelty shine through and feel satisfied by it. All in all, humans are by far the cruelest animals in the world.

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tarantula hawk eating nectar
tarantula hawk eating nectar
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About the Author

I'm a freelance writer with 8 years of experience. I've written in a variety of niches such as video games, animals, and managed service providers. I graduated from Rowan University in 2014 with degrees in English and Education. When I'm not working, I enjoy playing video games, reading, and writing for fun.

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