▽ The bodies of hermit crabs do not have a hard, protective carapace. ▽ These crabs have stalked eyes and a very good vision. They also have two pairs of antennae, one of which is used for feeling, while the other is used for smelling and tasting.

However, their size and prominence don’t mean that hermit crabs have perfect vision. Hermit crab eye anatomy enables them to see all around. Compound eyes mounted on stalks give hermit crabs 360-degree vision. This eyesight is restricted, though.

A reconstruction of what a female crab may see of a displaying male when her lenses are off. Female blue crabs (Callinectes sapidus) are literally blind when they choose their mates, according to new research from Duke biologists Jamie Baldwin and Sönke Johnsen.

Hermit crabs have corneal lenses in their eyes that reflect light. These are replaced during every molt. Hermit crabs regenerate eyestalks, though this can take 2-3 molts. Whether the eye itself also regenerates depends on the severity of the ocular damage during separation.

These results demonstrate that complete crab claws can regenerate from the eye sockets by autotransplantation of live limb tissue and that the regeneration is not due to the traumatic effect of transplantation.

Each time a crab molts it has the ability to regenerate the lost appendage. Regeneration in adult crabs takes one year due to the seasonal molting of adult females in fall and adult males in winter. The regenerated claws start out smaller than the original and will continue to grow through subsequent molts.

Vending Machines kill more people per year than sharks While the thought of a Coke machine probably doesn’t fill anyone normal with the same sense of dread as a Great White, vending machines are responsible for an average of 13 deaths a year.