'Rod-like cones' discovered in the eye of a deep-sea fish
It is known that the retina of most vertebrate animals, including humans, contain two photoreceptor types: rods for vision in dim light, and cones for daytime vision. However, Australia-based researchers have observed that deep-sea pearlside fish, which is active mostly in twilight, combine aspects of both cells into a single and more efficient photoreceptor type, dubbed as "rod-like cones".