|MadSci Network: Zoology|
Is it true that gorillas can't swim? I've actually heard this claim before; I also heard it regarding chimpanzees. Still, having heard the statement does not make it true. I've checked several sources, and I can find no reference to gorillas and swimming. There are some mentions in the monographs on gorilla behavior that these animals will avoid crossing streams -- but this includes streams that they could easily wade across. Clearly, swimming is not the issue, but rather that gorillas simply do not like to go into the water. As far as I know, no one has ever thrown a gorilla into the water and watched what happened. So, the only correct answer I give to your question is: I don't know. If you will allow me to indulge in some speculation, I may be able to come up with a reasonable guess as to basis of this idea. Every animal can float, simply because we have large air filled cavities in our bodies (the lungs). For most quadrupedal (four footed) animals, the act of swimming involves the same basic activities as the act of walking or running. Think about the "dog paddle." This means that the animal does not need to "learn" how to swim. It's basically moving about in the same fashion that it always does. Add to that, the fact that the basic quadrupedal body plan positions the nose and mouth so that they point forward, a quadrupedal animal can breath and swim at the same time. Now consider humans. For us, swimming involves the use of all four limbs in a way that is completely different to how they are used during walking. None of our walking and running skills translate well to swimming. In addition, our mouth and nose faces in the same direction as our belly, so that the mouth and nose are in the water when we swim. Without taking special actions (such as turning our head to the side) we cannot breath and swim at the same time. This means that for humans, swimming is basically a learned activity. It is not a natural extension of our normal behavior. Back to gorillas. A gorilla has a body structure that is sort of half way between that of humans and the basic quadruped. Its mouth and nose do not face toward its belly, but they do not exactly face forward either. Although the gorilla is a quadrupedal animal, it is also partially erect. This means that its normal walking pattern would not necessarily be completely effective as a swimming stroke. So, my best guess for an answer to your question is that gorillas can swim, but they are not very good at it. Given the choice, they will go to great lengths to avoid putting themselves in a position where they would need to swim. Still, I suspect that a gorilla could learn how to swim so as to be as good or better than most human swimmers.
Try the links in the MadSci Library for more information on Zoology.