Polyorchis: the lower rim of the bell of this hydrozoan jellyfish is lined with ocelli, patches of pigment and photoreceptor cells. The ocelli sense light and shadows. When night falls, they sense the darkness and move to the surface to feed. Polyorchis in a darkened jar, will automatically move up to the top of the jar, mimicking their nocturnal reaction to ocean light cycles.
	Garden Spider: Spiders generally have anywhere from 2-8 eyes that surround their head. Unlike most arthropods, their eyes are 'simple' rather than compound, as in most other arthropods. Two front-facing lens eyes act as their main image-forming apparatus. The other smaller simple eyes act as motion detectors and to extend the spider's field of view. Hunting spiders (as opposed to weaving spiders) depend more on accurate vision. To find out more: click here.
	Short-eared Owl: The eyes of owls take up such a large proportion of their skull, that their brain size is limited. As a nocturnal and flying bird, vision is essential for the hunting owl. Their large eyes allow increased light reception and larger, sharper images. Binocularity and precise accommodation give them good depth perception and acuity.
	Mosquito: like other flying insects, the mosquito has compound eyes. Compound eyes are made up of many tiny lense-lets that act like distinct eyes. The images from all the lense-lets (called ommatidia) are put together to make a large mosaic image of the mosquito's surroundings. This visual system allows for excellent motion detection, essential to any flying insect.
	A butterfly fish. Many species of fish use colouration to avoid predators. This fish hides its true eye with a strip of black and also has a false eyespot on its tail. When, a predator attempts to attack this false head, they find their prey swimming away in the opposite direction. To find out more about animals that hide their eyes, click here.
	Trumpet Fish: In order to streamline their eyes (for faster swimming), many fish have elliptical eyes that produces the least distortional friction and pressure. Many species also develop vertical lids — thin transparent tissue that covers the cornea to reduce, not only friction, but eddies that form around the eyes at high speeds. For more about underwater eye adaptations, click here
	Unknown tropical fish.Light does not penetrate water as it does air. Varying wavelengths of light are absorbed at different depths, the reds first, then yellows. At a depth of around 250m all that remains is a narrow band of blue-green (510nm-540nm). It makes good sense then that fish eyes have maximum sensitivity at 520nm. For more about underwater eye adaptations, click here

Back to our gallery about eye diversity and evolution - Who's Eye Is It Anyway?