Each eye is about the same volume as the animal's brain. Trilobites lived between 521 and ... these horsefly males have two different sized ommatidia (the photoreceptor units that form insects' ...

The presence of the tapetum can be observed at night when a pair of glowing eyes reflects back a flashlight or some other light source. (Interestingly, different animals have different color ...

We call this kind of eye a compound eye, and because all the little lenses point in different directions, animals that have them are very good at detecting movement – especially of big things ...

For many animals, the sound of a youngling causes quite a stir. Alligators are no different in this sense. In fact, a simple ...