Colour choices of naive bumble bees and their implications for colour perception

Abstract

The innate preferences of inexperienced bumble bees, Bombus terrestris, for floral colour stimuli were studied using artificial flowers. The artificial flowers provided a colour pattern and consisted of a star-shaped corolla and of central colour patches similar to the "nectar guide" of natural flowers. The innate choice behaviour was assessed in terms of the number of approach flights from some distance towards the artificial flowers and the percentage of approach flights terminating in antennal contact with the floral guide. The colours of the floral guide, the corolla and the background were varied. It was shown that the innate flower colour preference in bumble bees has two components. 1. The frequency of approaches from a distance is correlated with the colour difference between the corolla and the background against which it is presented. If the corolla colour was constant but its background colour varied, the relative attractiveness of the corolla increased with its colour difference to the background. The colour difference assessment underlying this behaviour on a perceptual basis can be attained by means of colour opponent coding, a system wellestablished in Hymenoptera. 2. The frequency of antennal contacts with the floral guides relative to that of approach flights cannot be accounted for by colour opponent coding alone. Whether the approach flights are interrupted, or whether they end in an antennal

Illumination preference, illumination constancy and colour discrimination by bumblebees in an environment with patchy light

“…In the colour hexagon, the angular position as defined from the centre defines hue, which is in turn determined by the relative receptor excitation signals -a position in the top part of the hexagon, for example, indicates a relative strong stimulation of the blue receptor. Distance from the centre defines spectral purity, so that colour loci further from the centre might be perceived as more saturated (Lunau et al, 1996). Colour loci are shown for the two types of artificial flowers, i.e.…”

Plantas, polinizadores e algumas articulações da biologia da polinização com a teoria ecológica

“…Esse pesquisador registrou que a pureza espectral da cor da corola é um fator crucial na atração à distância para as flores. Em experimentos semelhantes Lunau et al (1996) mostraram que a diferença de cor entre a corola e o centro da flor estão correlacionadas positivamente com a frequência de visitas, ou seja, quanto maior a distância entre essas cores, mais visitas. Quando se considerou apenas as visitas de abelhas que contactaram as antenas nas flores artificiais houve uma grande influência do sentido em que apontava a diferença de cor.…”

“…Quando se considerou apenas as visitas de abelhas que contactaram as antenas nas flores artificiais houve uma grande influência do sentido em que apontava a diferença de cor. Assim, a saturação foi o atributo mais importante e as flores com a cor do centro mais saturada foram as mais visitadas, indicando uma preferência inata a este padrão de cor floral (Lunau et al 1996).…”

Getting to the start line: how bumblebees and honeybees are visually guided towards their first floral contact

“…the degree to which there is one dominant vs. a mix of wavelengths (Lunau, 1990(Lunau, , 1992Papiorek et al, 2013;Rohde et al, 2013). Corollas with high spectral purity are approached from afar (Lunau et al, 1996). Flowers incite inspection (Bombus lucorum (L., 1761) and B. terrestris (L., 1758)) with a gradient of spectral purity: low in the background, high at the corolla and highest at floral guides such as stamens.…”