It was pretty good not the bestcould use better graphics.
The lung volume starts rising again when the whale stays at 500 m depth, that's not physiologically correct imho. It would be nice to add the lungs themselves to the whale as well, so you can show them being pressed together by the water pressure on the body. Or add a balloon, you can easily model it's volume in function of the depth. That illustrates nicely what goes on. It's nice to add weights as well, symbolizing the pressureby the water column.
Interesting. As an informational tool, I suggest that adding some text to the two info tabs might help explain the process, i.e., giving an easily digestible explanation of the process, its effects, and the reasons such effects occur. Also, highlight effects on the buttons might be good to show if the animation is stopped, at slow speed, normal, playing, etc. Just a recommendation. But other than, it's pretty straightforward for what it's geared to. Other than a little white border I'm seeing at the right and bottom edges, it all looks pretty solid.
If people give really negative reviews, well, they forget it's just to teach about how whales are affected by deep pressure. Not provide a transcendent gaming experience. =p
Waaaaay to go mate - for example:
Those teense bits of info in those two tabs? They would've easily fitted into one. There's also nothing telling one why the lungvolume is shrinking (compression due to pressure), how high such a pressure is, an easy to get comparison (like 1m of water over a squaremeter equals 1t), biological background etc.
If you're telling that all "by the way" while showing this rather . . . simple . . . piece, you might as well leave the animation out. This way no one will be distracted by another thing (I've allways been drawing swords while in school).