No noseclip

Seals are incredible: they have muscles in their nostrils that can close the nose off completely, blood vessels in their middle ear to help compensate the pressure, and to improve streamlining, they can even retract their nipples -which is a pretty cool party-trick.



Photo found here: http://www.flickr.com/photos/immortal-thrill-seeker/3094977418/sizes/l/