Avian Ultraviolet Vision And Frequency-Dependent Seed Preferences

It is well established that ultraviolet sensitivity plays an important role in the visually guided behaviour of birds. From a foraging perspective, evidence now exists that ultraviolet wavelengths are used by birds when foraging for insects, berries, seeds and mammals. Here, we present the results of two laboratory experiments that test the effect of removing […]

Is the ultraviolet waveband a special communication channel in avian mate choice?

There is growing evidence that ultraviolet (UV) wavelengths play an important role in avian mate choice. One of the first experiments to support this idea showed that female zebra finches (Taeniopygia guttata) prefer UV-reflecting males to males whose ultraviolet reflection has been removed. The effect was very strong despite little or no UV reflection from […]

Sensory Ecology of Feeding in the Hummingbird Hawkmoth Macroglossum stellatarum (Lepidoptera: Sphingidae)

The European hummingbird hawkmoth, Macroglossum stellatarum (Linnaeus 1758), drinks nectar while hovering in front of flowers of all colours, odours, sizes and shapes. Naive moths orient predominantly towards visual stimuli and prefer blue flowers with a radial pattern and a central contrasting spot. Hummingbird hawkmoths have trichromatic colour vision and can learn any colour and […]

Photoreceptor sectral sensitivities in terrestrial animals: adaptations for luminance and colour vision

This review outlines how eyes of terrestrial vertebrates and insects meet the competing requirements of coding both spatial and spectral information. There is no unique solution to this problem. Thus, mammals and honeybees use their long-wavelength receptors for both achromatic (luminance) and colour vision, whereas flies and birds probably use separate sets of photoreceptors for […]

Interspecific and intraspecific views of color signals in the strawberry poison frog Dendrobates pumilio

Poison frogs in the anuran family Dendrobatidae use bright colors on their bodies to advertise toxicity. The species Dendrobates pumilio Schmidt 1858, the strawberry poison frog, shows extreme polymorphism in color and pattern in Panama. It is known that females of D. pumilio preferentially choose mates of their own color morph. Nevertheless, potential predators must […]

The Intra-Ocular Colour Filters of Vertebrates

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The Ecology of Color Vision

Colour vision in man is well understood, but for obvious experimental reasons it is less so in the case of other animals. Some evidentally have a three-colour system similar to our own but based on different primary colours. In particular, some are sensitive to ultraviolet light, which the human eye is not.

Why Aye-Ayes See Blue

The capacity for cone-mediated color vision varies among nocturnal primates. Some species are colorblind, having lost the functionality of their short-wavelength-sensitive-1 (SWS1) opsin pigment gene. In other species, such as the aye-aye (Daubentonia madagascariensis), the SWS1 gene remains intact. Recent studies focused on aye-ayes indicate that this gene has been maintained by natural selection and […]

A Review of the Evolution of Animal Colour Vision and Visual Communication Signals

The visual displays of animals and plants are often colourful, and colour vision allows animals to respond to these signals as they forage for food, choose mates and so-forth. This article discusses the evolutionary relationship between photoreceptor spectral sensitivities of four groups of land animals–birds, butterflies, primates and hymenopteran insects (bees and wasps)–, the colour […]