# Do any 2 animals regularly prey on each other? **URL:** \ **Category:** Factual Questions\ **Created:** [June 21, 2011, 5:44pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313 "2011-06-21T17:44:02Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![SmithCommaJohn](https://avatars.discourse-cdn.com/v4/letter/s/ecd19e/32.png) [@SmithCommaJohn](https://boards.straightdope.com/u/SmithCommaJohn)\ **Post date:** [June 21, 2011, 5:44pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/1 "2011-06-21T17:44:02Z")
Are there any two animals that regularly hunt, kill, and eat each other? Basically, are there two species which each have roughly a 50/50 chance of successfully hunting, or being hunted by, the other? For example, in the Florida Everglades, alligators and invasive Burmese pythons seem quite adept at killing one another. But that involves a non-native species. Has such a situation arisen naturally? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 21, 2011, 6:03pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/2 "2011-06-21T18:03:42Z")
Happens all the time, if you consider different life stages. For example, monitor lizards eat crocodile eggs and baby crocs, while being eaten by adult crocs. Likewise raccoons and alligators. When it comes to adults, a predator is generally not going to try to tackle a prey animal that has a 50% chance of winning! However, I would guess that occasional conflicts take place between adult crocs and anacondas, or adult crocs and jaguars - but it wouldn’t be a regular thing. ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [June 21, 2011, 6:42pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/3 "2011-06-21T18:42:15Z")
Predation is a gamble; a species that routinely makes bad bets (or even bets that aren’t heavily in its favor) is going to be at a severe disadvantage when it comes to surviving from generation to generation. In specific, a predator is betting that its caloric outlay in stalking and killing a specific prey animal is going to be repaid many, many times over when it kills and eats the animal, and that it isn’t going to lose a significant amount of calories and/or hunting or mating effectiveness due to injuries or illnesses sustained due to the hunt. It might be interesting to think about the worst bet routinely made in the animal kingdom; a cheetah hunting wildebeest, perhaps, or anything going after a hippo. (Both those are improved by the fact juveniles and the ill are most commonly targeted.) ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 21, 2011, 7:04pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/4 "2011-06-21T19:04:00Z")
Are we allowed to count humans as one of the species? Because armed humans often (though maybe not routinely) hunt, kill, and eat species which would easily kill and eat unarmed humans. > [@](#): > > It might be interesting to think about the worst bet routinely made in the animal kingdom; a cheetah hunting wildebeest, perhaps, or anything going after a hippo. (Both those are improved by the fact juveniles and the ill are most commonly targeted.) More interesting is when lions go after young elephants. The mother elephant has been known to respond by hunting down and killing the lioness and all of her cubs. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [June 21, 2011, 7:06pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/5 "2011-06-21T19:06:10Z")
> [@SmithCommaJohn](#): > > Basically, are there two species which each have roughly a 50/50 chance of successfully hunting, or being hunted by, the other? Black spies and white spies? ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [June 21, 2011, 7:15pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/6 "2011-06-21T19:15:42Z")
Would lions and hyenas fall into that group? Seems like whenever a pack of one kind finds a lone member of the other, it’s on. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 21, 2011, 7:23pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/7 "2011-06-21T19:23:03Z")
> [@lieu](#): > > Would lions and hyenas fall into that group? Seems like whenever a pack of one kind finds a lone member of the other, it’s on. Probably true. However, in this case it may be more a case of interspecific territoriality between competing predators than an intent to take the other as prey. ---
**Author:** ![Cryptic\_C62](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@Cryptic\_C62](https://boards.straightdope.com/u/Cryptic_C62)\ **Post date:** [June 21, 2011, 7:47pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/8 "2011-06-21T19:47:04Z")
I’m surprised that mongooses and snakes haven’t been mentioned yet. Mongooses hunt smaller snakes for food, but larger snakes can kill and eat mongooses too. There are videos of both results on YouTube. Also, [here](http://www.schweizerbart.de/papers/fal/detail/157/55504)’s a study of mutual predation (the technical term for the phenomenon being discussed) between various species of scuds. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 21, 2011, 7:51pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/9 "2011-06-21T19:51:11Z")
Of course, I’m sure that whichever one wins eats the other anyway, even if that wasn’t the original purpose of the confrontation. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [June 21, 2011, 8:22pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/10 "2011-06-21T20:22:46Z")
**Do any 2 animals regularly prey on each other?** Not for very long. Unless you’re talking about species and not just 2 animals. ---
**Author:** ![MysteryFellow63427](https://avatars.discourse-cdn.com/v4/letter/m/a88e4f/32.png) [@MysteryFellow63427](https://boards.straightdope.com/u/MysteryFellow63427)\ **Post date:** [June 21, 2011, 10:37pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/11 "2011-06-21T22:37:09Z")
> [@Chronos](#): > > More interesting is when lions go after young elephants. The mother elephant has been known to respond by hunting down and killing the lioness and all of her cubs. On the surface, this claim seems somewhat fantastic to me. Might you have a cite for it? ---
**Author:** ![Spoke](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@Spoke](https://boards.straightdope.com/u/Spoke)\ **Post date:** [June 21, 2011, 11:20pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/12 "2011-06-21T23:20:54Z")
Back in the day, humans and bears. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [June 21, 2011, 11:37pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/13 "2011-06-21T23:37:49Z")
> [@neuroman](#): > > On the surface, this claim seems somewhat fantastic to me. Might you have a cite for it? I don’t have the cite, but I believe it’s well established. Cape buffalo and other large cattle will intentionally trample lion cubs, though they don’t go very far to hunt them down, mostly just accidental encounters. Elephants have the intelligence and ability to hunt and kill lions, with malice aforethought. Lions and hyenas are also mortal enemies, hunting and killing each other when they can. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [June 22, 2011, 3:40am UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/14 "2011-06-22T03:40:37Z")
“some days the bull wins” ---
**Author:** ![bahimes](https://avatars.discourse-cdn.com/v4/letter/b/e36b37/32.png) [@bahimes](https://boards.straightdope.com/u/bahimes)\ **Post date:** [June 22, 2011, 5:50am UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/15 "2011-06-22T05:50:27Z")
Criadillos? ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [June 22, 2011, 8:42am UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/16 "2011-06-22T08:42:11Z")
> [@Cryptic\_C62](#): > > I’m surprised that mongooses and snakes haven’t been mentioned yet. Mongooses hunt smaller snakes for food, but larger snakes can kill and eat mongooses too. Yes, but is the snake the mongoose eats the same species as the snake that eats the mongoose? ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [June 22, 2011, 9:22am UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/17 "2011-06-22T09:22:27Z")
> [@TriPolar](#): > > I don’t have the cite, but I believe it’s well established. Cape buffalo and other large cattle will intentionally trample lion cubs, though they don’t go very far to hunt them down, mostly just accidental encounters. Elephants have the intelligence and ability to hunt and kill lions, with malice aforethought. I’ve seen footage of Buffalo chasing lion cubs. However, I’m very dubious about the concept of a vengeful Elephant on the hunt. A proper cite would be interesting. To answer the OP, the reason you don’t often see evenly matched animals **predating** on each other is that it would be a very poor evolutionary strategy. To survive and breed, a predator needs to kill many animals. If they only have a 50% chance of winning each encounter, their chances of survival are very slim. Predators have evolved to be opportunistic, they will typically pick off the weakest prey available. They usually only go after the strongest animals when they are desperate. However, you do often see evenly matched animals fighting for either mates or territory. Usually, this is combat between members of the same species. However, most fights are not to the death. ---
**Author:** ![Crazyhorse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crazyhorse/32/31_2.png) [@Crazyhorse](https://boards.straightdope.com/u/Crazyhorse)\ **Post date:** [June 22, 2011, 10:05am UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/18 "2011-06-22T10:05:07Z")
There are plenty of examples of lions attacking elephants and sometimes getting killed in the process, and sometimes getting an elephant for dinner. They try to make sure its better than a 50/50 chance by isolating a cub or weak member from the pack and hoping that the others just let it go in order to save themselves. Elephants are one of the animals that sometimes don’t just let it go and they can stomp or gore the lion to death successfully sometimes. It ain’t easy making a living out there even for lions or elephants. I can’t find any evidence, or anecdotal claims other than in this thread, that elephants are known to plot the demise of unknown lion enemies and go out with the intention of hunting them down and killing them. Not saying it’s not true but I’d love to see a cite on that too. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [June 22, 2011, 1:18pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/19 "2011-06-22T13:18:23Z")
I don’t know about vengefulness, but I believe it’s generally accepted that some herbivores will intentionally kill the young of their predator species when they can get away with it. This tendency was discussed as a possible behavior of dinosaurs in a program I saw, where it was extrapolated from known behaviors of modern animals. ---
**Author:** ![Koxinga](https://avatars.discourse-cdn.com/v4/letter/k/4af34b/32.png) [@Koxinga](https://boards.straightdope.com/u/Koxinga)\ **Post date:** [June 22, 2011, 1:52pm UTC](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313/20 "2011-06-22T13:52:41Z")
Don’t predator species make a lousy choice of meat for another predator (as opposed to a scavenger)? For humans at least, I’ve read that eating the liver of a lion or polar bear is a Very Bad Idea. [Next page](https://boards.straightdope.com/t/do-any-2-animals-regularly-prey-on-each-other/586313.md?page=2)