Fish eating their own fry/eggs

[rallysb1tch]

This might be a stupid question and the answer might be very obvious, but I've always wondered why there are fish (or any other animal for that matter--hamsters,etc.) that eat their offspring. It just seems counterproductive to me. Why would nature allow for wasting precious time and energy like this? Is it just in captivity or does this happen in the wild as well?

Heh, these are the questions I think of when I'm at work on a Friday with less than 30 minutes left in my work day.

 

[beblondie]

If they didn't you'd be butt high in hamsters,ffish and alligators its a form of natural population control

 

[rallysb1tch]

If they didn't you'd be butt high in hamsters,ffish and alligators its a form of natural population control

Very good point, but this raises another question with me.

I've often heard that some animals can delay or terminate a pregnancy if conditions are not favorable--why do fish not do this if competition for food and space is limited? I first thought that the eggs/fry would provide them with much needed nutrition but wouldn't the energy used to create the offspring be greater than the energy they gain from eating it?

 

[repair]

Wait untill you have teenagers.... you'll understand

 

[Nabbig2]

Very good point, but this raises another question with me.

I've often heard that some animals can delay or terminate a pregnancy if conditions are not favorable--why do fish not do this if competition for food and space is limited? I first thought that the eggs/fry would provide them with much needed nutrition but wouldn't the energy used to create the offspring be greater than the energy they gain from eating it?

Because if conditions are bad, the young will not thrive, and they will die, like if there is not enough food. They won't give birth just to eat; they would rather save the sperm until there are good resources.

 

[rallysb1tch]

Wait untill you have teenagers.... you'll understand

I'll never know because that's not going to happen

 

[ddyerfamily]

good questions......natural selection I think........
makes you think about what we do to save species.......that
might other wise be extinct. not natural at all.
but.....we caused some losses.

 

[ewurm]

Perhaps they know better.

 

[Wolf3101]

VERY few of any single fish spawn live long enough in nature to spawn themselves so theres no real reason for self regulation. The main reason it happens in aquaria is either the pairs inexpierance....compitition for space or there bieng something wrong with the eggs themselves.

 

[Nabbig2]

VERY few of any single fish spawn live long enough in nature to spawn themselves so theres no real reason for self regulation. The main reason it happens in aquaria is either the pairs inexpierance....compitition for space or there bieng something wrong with the eggs themselves.

Yup. For example, discus fish eat the unfertilized eggs to prevent the fungus from growing and spreading to the good eggs.