Search results
Results from the WOW.Com Content Network
In humans, the pupil is circular, but its shape varies between species; some cats, reptiles, and foxes have vertical slit pupils, goats and sheep have horizontally oriented pupils, and some catfish have annular types. [3] In optical terms, the anatomical pupil is the eye's aperture and the iris is the aperture stop.
Cephalopods, as active marine predators, possess sensory organs specialized for use in aquatic conditions. [1] They have a camera-type eye which consists of an iris, a circular lens, vitreous cavity (eye gel), pigment cells, and photoreceptor cells that translate light from the light-sensitive retina into nerve signals which travel along the optic nerve to the brain. [2]
The arroyo toad is a stocky, blunt-nosed, warty-skinned species of toad, 5 to 7.5 cm (2.0 to 3.0 in) long.It has horizontal pupils, and is greenish, grey or salmon on the dorsum with a light-colored stripe across the head and eyelids.
Unlike other toads which have horizontal pupils, spadefoot toads have vertical pupils. On the underside of the hind foot is a hard, dark "spade" that gives spadefoot toads their name. These creatures can grow to be 3.5" in length. These "spades" are used by the toads to burrow into the ground to prevent water loss and hide from predators.
Last but not least, the position of the eyes on an octopus' head and its horizontal pupils mean that the animals have 360° vision with no "blind spots". Who can beat that? Nikon D800, Tokina 3.5 ...
It has a white or cream dorsal stripe, and is dusky gray or greenish dorsally with skin glands concentrated within the dark blotches. Its parotoid glands are oval, widely separated, and larger than the upper eyelids. It has a mottled venter and horizontal pupils but lacks cranial crests.
The last common ancestor of animals possessed the biochemical toolkit necessary for vision, and more advanced eyes have evolved in 96% of animal species in six of the ~35 [a] main phyla. [1] In most vertebrates and some molluscs , the eye allows light to enter and project onto a light-sensitive layer of cells known as the retina .
The tapetum lucidum, in animals that have it, can produce eyeshine, for example as seen in cat eyes at night. Red-eye effect, a reflection of red blood vessels, appears in the eyes of humans and other animals that have no tapetum lucidum, hence no eyeshine, and rarely in animals that have a tapetum lucidum. The red-eye effect is a photographic ...