Spookfish Sees Things Like Nobody Else Ever Has

Of all the animals in the world, the lowly spookfish has the oddest eyes — compound mechanisms that bear more than a passing resemblance to rearview mirrors.

The bottom half of its eyes point upwards. The upper half point downwards, and are backed with a layer of reflective guanine crystals that bounce a focused image into the retina.

The titular disclaimer comes from reading this:

Researchers tested the eyes by taking flash photographs from above and below a live spookfish, then dissecting its eyes.

(there’s also this article)