Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

When I checked it seemed trivial to answer: yes, all mammals can swim. But research on the internet provided different information. I found:

Of each hit, I found other hits that claimed the reverse, sometimes with proof. Common sense tells me all mammals can swim, but is this true?

share|improve this question
There are over 5,000 species of named, extant mammals. So to show that all can (or cannot) swim would be a monumental task. –  kmm Apr 15 '12 at 19:09
@Kevin: fair enough. Yet, to prove that all mammals can swim may require research on each of the species, but to prove the opposite only requires proof that one species really can't swim. –  Abel Apr 15 '12 at 21:50
Well, what is your definition of swimming? That needs to be cleared before getting any further. –  CHM Apr 15 '12 at 22:50
@CHM: the way I see it, moving through the water without drowning and without walking on the bottom of the river/lake. –  Abel Apr 15 '12 at 23:02

2 Answers 2

up vote 6 down vote accepted

With respect to the giraffe claim, this article seems relevant:

D. M. Henderson, D. Naish, Predicting the buoyancy, equilibrium and potential swimming ability of giraffes by computational analysis, J Theoretical Biology 265 (2010) 151-159.

It cites several non-"random person on the internet" claims that giraffes cannot swim:

It is generally thought that giraffes cannot swim, but relevant observations are few. Shortridge (1934) and Goodwin (1954) state that giraffes were poor waders and unable to swim. Crandall (1964) discussed a case where a captive giraffe escaped from a carrying crate, ran to the end of a jetty, and fell into the water. The animal reportedly sank without making any attempt to swim. MacClintock (1973, p. 54) stated ‘Giraffes cannot swim. Rivers are barriers they do not cross’. Wood (1982, p. 20) noted that ‘Because of its extraordinarily anatomical shape the giraffe is one of the very few mammals that cannot swim – even in an emergency! Deep rivers are an impassable barrier to them, and they will avoid large expanses of water like the plague’.

They then go on to show that a model giraffe could plausibly swim, writing: "For practical and ethical reasons we are unable to use live giraffes..."

They conclude:

In summary, the results and speculations of this study show that it is not impossible that a giraffe could propel itself in water, but in terms of energy efficiency relative to that of the horse, it would appear that the costs of aquatic locomotion might be too high. It is reasonable to expect that giraffes would be hesitant to enter water knowing that they would be at a decided disadvantage compared to being on solid ground.

share|improve this answer
+1 Interesting, nice find! I just found out that hippos can't swim either, because they're too dense and would sink. They "walk" across the bottom. –  Abel Apr 16 '12 at 13:29

I have found videos of porcupines, armadillos, anteaters.. all swimming. The porcupine seemed to have no trouble at all.

As for apes - quite well it seems. http://newswatch.nationalgeographic.com/2013/08/20/new-surprising-video-shows-apes-swimming/

Rhinos: www.youtube.com/watch?v=DbqF4AA0Z8U The water looks deeper than it's head at times, for sure. But whether it is actually swimming or can just/almost reach the bottom is unclear.

Giraffes: http://www.arkive.org/giraffe/giraffa-camelopardalis/video-ti06.html

It seems to me that if these animals couldn't manage at all in the water, that they wouldn't likely do so, from an evolutionary standpoint.

I'm sure not all manage terribly well, but the videos seem to show that they managed at least.

Pretty cool. :)

share|improve this answer
The video of the giraffes shows that they don't swim, as the moment that they consider it too deep, they instantly return to shore. And indeed, the rhino walks across the bottom of the riverbed. –  Abel Jan 29 '14 at 15:38

protected by WYSIWYG yesterday

Thank you for your interest in this question. Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.