Humans are colour-blind at night, and it has been assumed that this is true of all animals.
But colour vision is as useful for discriminating objects at night as it is during the day. Here …

AT night all cats are grey, but with the approach of dawn they take on colour. By starlight, a
single class of photoreceptors, the rods, function, whereas by daylight, three classes, the …

Most mammals, with the exception of primates, have dichromatic vision and correspondingly
limited colour perception. Ultraviolet vision was discovered in mammals only a decade ago …

The ability to see colour at night is known only from a handful of animals. First discovered in
the elephant hawk moth Deilephila elpenor, nocturnal colour vision is now known from two …

Light can be described by its intensity, spectral distribution and polarization, and normally a
visual system analyses these independently to extract the maximum amount of information …

Light discrimination according to colour can confer survival advantages by guiding animals
towards food and shelter and away from potentially harmful situations,. Such colour …

AFTER exposure to light, the rhabdomeres1, 2 and cytoplasmic components3, 4 of the visual
cells of invertebrates undergo structural changes. These changes are important, for they …

Sm-Most human observers enjoy trichromatic v1s10n: a three-dimensional colour space
represents all the light that they can discriminate1• Two per cent of the male population are …

The dual retina of humans and most vertebrates consists of multiple types of cone for colour
vision in bright light and one single type of rod, leaving these animals colour-blind at night …

Abstract BEHAVIOURAL1, 2 and electrophysiological3 experiments have shown that the
insect eye responds to ultraviolet irradiation. In the eye of the honeybee there is only a small …