RT Journal Article
SR Electronic
T1 Environmental and hormonal factors controlling reversible colour change in crab spiders
JF The Journal of Experimental Biology
JO J. Exp. Biol.
FD The Company of Biologists Ltd
SP 3886
OP 3895
DO 10.1242/jeb.086470
VO 216
IS 20
A1 Llandres, Ana L.
A1 Figon, Florent
A1 Christidès, Jean-Philippe
A1 Mandon, Nicole
A1 Casas, Jérôme
YR 2013
UL http://jeb.biologists.org/content/216/20/3886.abstract
AB Habitat heterogeneity that occurs within an individual's lifetime may favour the evolution of reversible plasticity. Colour reversibility has many different functions in animals, such as thermoregulation, crypsis through background matching and social interactions. However, the mechanisms underlying reversible colour changes are yet to be thoroughly investigated. This study aims to determine the environmental and hormonal factors underlying morphological colour changes in Thomisus onustus crab spiders and the biochemical metabolites produced during these changes. We quantified the dynamics of colour changes over time: spiders were kept in yellow and white containers under natural light conditions and their colour was measured over 15 days using a spectrophotometer. We also characterised the chemical metabolites of spiders changing to a yellow colour using HPLC. Hormonal control of colour change was investigated by injecting 20-hydroxyecdysone (20E) into spiders. We found that background colouration was a major environmental factor responsible for colour change in crab spiders: individuals presented with white and yellow backgrounds changed to white and yellow colours, respectively. An ommochrome precursor, 3-OH-kynurenine, was the main pigment responsible for yellow colour. Spiders injected with 20E displayed a similar rate of change towards yellow colouration as spiders kept in yellow containers and exposed to natural sunlight. This study demonstrates novel hormonal manipulations that are capable of inducing reversible colour change.