Re: Are there any animals that have more than one functioning mouth?

Hi Kristin.

That's a very interesting question. In answer to your question I should say that I don't know. There might be some rare exotic animals with more than one mouth (frogfish?) but I haven't got a source. The problem with this question is that first we have to define what mouth is. If you say mouth is simply a hole through which things enter and not exit (like the anus), then I know of some animal that has many mouths. Of course, it's the sponge. Through the pores (hence the names porifera), the water and nutrients enter the cells. The digestion is intracellular and the water leaves the organism through the osculum (a large opening). Here's a website on sponges. http://www.animalnetwork.com/fish/aqfm/1998/jan/wb/default.asp

If you look at the themes in evolution, you will notice that having one mouth has been favored. I can not think of any great advantages to having more than one mouth. Of course the animal can 'ingest' the food faster, but the digestion rate would remain the same (unless the animal has as many stomachs and digestive glands as well). We haven't even looked at the possible problems with having many mouths for the process of swallowing. Is all the food going to go down simultaneously or from one mouth then the next. If the animal has sharp teeth (if mammal) or a radula (snail), then the mouths could be somewhat useful for defense. Then there is the question of necessity. Someone recently asked me why do we have five fingers and not six. I think the answer to this person's question is the same to the question at hand. Maybe the evolution doesn't like to have the animal go through big changes (having many mouths requires different nervous system specialization for example) which will result in not that big of a difference in animal's success.

Think about it!

A very good question you asked indeed!

A.E.

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