“Here in the Pacific, 200 metres down, we enter an alien world… This is barreleye a fish with a transparent head filled with jelly so that it can look up through its skull.” – Sir David Attenborough
Blue Planet II
most fish just grow their eyes on the sides of they head but okay
They do that because it lets them look up and spot fish that are silhouetted against the light coming from above, and because it gives them a really wide field of vision, but keeps their eyes tucked inside and protected.