Does Cockroach Have Eyes?
WouterYou may be wondering if cockroaches have eyes. They are not obligate nocturnal creatures, but they do like to stay indoors during the day, and they see through 2,000 individual lenses. Cockroaches are able to detect light in different wavelengths, and their eyes are sensitive to both red light and daylight. Besides their eyes, cockroaches have antennae that move and are made of thin segments. The segments are thicker near the head and thinner at the tip. Cockroaches also have two sets of lips, called labrum and labium. Two mandibles have cutting surfaces and two maxillae are used for manipulating food.
Cockroaches’ compound eyes are composed of around 2,000 hexagonal lenses. This is much more than human eyes have, and it gives them superb vision. They have an excellent peripheral vision and can perceive more than one object at a time. In contrast, humans can only see one huge image.
Cockroaches have excellent vision, though their lenses tend to become increasingly distorted near the outer edge of the eye. However, there is very little cause for concern about this condition. Though roaches are blind in red light, they see fairly well in green light. Cockroaches can also live without a head for extended periods of time without any visual impairment.
In addition to detecting light, the ocelli of the American cockroach can be influenced by ambient light intensity. The output from the ocelli can modulate the behavioural responses of the animal.
