I was seeing this yewtube video showcasing SGI Irix's 3D demos: https://www.youtube.com/watch?v=aqcc2lm0L9Q

And when i spotted those sharks on the aquarium demo, i immediately recognized them: they are the same (or so i think, they are very similar) 3D model used in the desktop cube aquarium for the Compiz Fusion window manager.

Here's a screenshot of my desktop from 2009 or 2010. At that time, i was using Ubuntu with the Compiz Fusion compositing window manager. I was using the desktop cube with the aquarium plugin (i think it was called “atlantis”, from what i could search on the webz). The aquarium features fishes and crabs and algae while rotating the cube to change the current desktop.