Is there an organism that's compilsively cannibalistic?

Question

Is there an organism that can only live by feeding on its own kind, and it does get any nourishment by feeding on anything else?

Thanks.

Is there an organism that can only live by feeding on its own kind, and it does get any nourishment by feeding on anything else?

If not, how about an organism that has preference to eating its own kind over any other food?

Answer 1

As you phrased it, yes, lots of. They're called fish. Almost all of them will eat their own young, at least in aquaria. If you dropped a word and meant 'does NOT get nourishment', then no. That would be impossible. Any creature that exclusively ate its own would violate the law of thermodynamics. A closed biological system is incapable of growth.

Answer 2

There are lots of creatures that eat their own kind. But it is impossible that all they eat is their own kind. If there was no energy coming from outside sources, they would eventually all die off. Think about if you put a bunch of crickets in a container and gave them no food. They would start eating each other very quickly (they are very cannibalistic when put together). There might even be enough crickets that they could breed and have babies. But because they can not use all the energy, and also because they are using it in a way that can't be recovered (to grow and move, etc), they will eventually run out of food. It just doesn't work.

Answer 3

Although I do not have a categoric answer - looking for it revealed an interesting side fact.

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Frogfish can be troublesome for the home aquarist. They are cannibals, which means they will eat their own kind. Putting two of them in a home aquarium together often results in one getting eaten by the other.
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It seems they cannot get on with another frogfish!!

That said I can find no organism that is exclusively cannibalistic, maybe someone has an example . . . . I would love to see it.

Answer 4

There are no exclusive cannibals. All animals will eat other things, some just happen to eat eachother, but they don't exclusively do that. If they did, then eventually they would all die out, so it's not productive to only eat it's own kind.

Answer 5

I do not think so. But few animals, including, some household pets, like cats, eat the new born, its own progeny, because of unbearable hunger.

Answer 6

Wolverines are known to be cannibalistic.

Answer 7

there was but it died out as the last one ate it's self

Answer 8

bacteria devours itself when there is no more room.