Squid eyes are the size of dinner plates

The colossal squid lives in total darkness, so it evolved eyes the size of standard soccer balls. Measuring up to 11 inches across, these are the largest eyes ever documented in the animal kingdom.

These massive orbs aren't for seeing detail; they are designed to detect light. Specifically, they are tuned to spot the movement of bioluminescent organisms disturbed by a nearby sperm whale.

By detecting the faint glow of plankton as a whale swims through them, the squid can see the silhouette of its only predator from over 400 feet away in the pitch black.

A lens the size of an orange helps focus every stray photon of light into the retina. This gives the squid a massive advantage in the abyssal depths where light is practically nonexistent.

Interestingly, the squid's brain is shaped like a donut, and its esophagus passes directly through the center. If it swallows a meal that is too large, it can actually cause permanent brain damage.