# Guppy populations self limiting



## Endler Guy (Aug 19, 2007)

I've often wondered why some people's guppies eat their own young while others don't. I've just come across this study. An interesting read.


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## mistergreen (Mar 3, 2007)

it makes sense.. You see over population drive animals to infanticide not just guppies. This could drive people too but it's much more complicated.


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## aquabillpers (Apr 13, 2006)

Overcrowded populations stress the inhabitants and that stress leads to sickness and death. In a natural environment, the excess population migrates to a less populated area if it can. Lemmings are a good example of that.

I don't think that animals attempt to limit their numbers by infanticide. Guppies eat their young if they are not fed enough, whether they are crowded or not. Kribs, on the other hand, will attempt to raise a brood of 50 in a 10 gallon aquarium and defend the fry to the death, even though the aquarium is grossly overcrowded.

Bill


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## Endler Guy (Aug 19, 2007)

I suppose that's the difference between guppies and kribs. In the study, when minnows were added to the mix, the guppies ate fewer young. Also, water changes with water form aquariums containing other species, ramped up guppy production. They seem to be able to sense the competition. So, it's highly unlikely that water quality was controlling the population but that the guppies were. I wish I could read the rest of that article.


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