ADVERTISEMENT
Nautilus
Only 6 species of Nautilus remain today, out of hundreds that used to inhabit the oceans. Nautilus has an incredible shell that works as a submarine and has chambers that can be filled with water or gas when the creature needs to go deeper or ascend. Apart from ‘driving’ the very first ‘submarine’ that’s ever been invented, these creatures haven’t really changed at all during the past 500 million years or so.
