Marine Resources Center (MRC)
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The Marine Resources Center (MRC) is a highly advanced facility for maintaining, culturing, and providing aquatic organisms essential to advanced biological, biomedical, and ecological research. Research is partitioned into two programs: The Program in Sensory Biology and Neuroethology; and The Program in Scientific Aquaculture.
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Browsing Marine Resources Center (MRC) by Subject "Camouflage"
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DatasetDynamic masquerade with morphing 3D skin in cuttlefish( 2017-02-03) Panetta, Deanna ; Buresch, Kendra C. ; Hanlon, Roger T.Masquerade is a defence tactic in which a prey resembles an inedible or inanimate object thus causing predators to misclassify it. Most masquerade colour patterns are static although some species adopt postures or behaviours to enhance the effect. Dynamic masquerade in which the colour pattern can be changed is rare. Here we report a 2-step sensory process that enables an additional novel capability known only in cuttlefish and octopus: morphing 3D physical skin texture changes that further enhance the optical illusions created by the coloured skin patterns. Our experimental design incorporated sequential sensory processes: addition of a 3-dimensional rock to the testing arena, which attracted the cuttlefish to settle next to it; then visual processing by the cuttlefish of physical textures on the rock to guide expression of the skin papillae, which can range from fully relaxed (smooth skin) to fully expressed (bumpy skin). When uniformly white smooth rocks were presented, cuttlefish moved to the rock and deployed a uniform body pattern with mostly smooth skin. When a rock with small-scale fragments of contrasting shells was presented, the cuttlefish deployed mottled body patterns with strong expression of papillae. These robust and reversible responses indicate a sophisticated visual sensorimotor system for dynamic masquerade.
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ArticleTo be seen or to hide : visual characteristics of body patterns for camouflage and communication in the Australian giant cuttlefish Sepia apama(University of Chicago, 2011-04-06) Zylinski, S. ; How, M. J. ; Osorio, D. ; Hanlon, Roger T. ; Marshall, N. J.It might seem obvious that a camouflaged animal must generally match its background whereas to be conspicuous an organism must differ from the background. However, the image parameters (or statistics) that evaluate the conspicuousness of patterns and textures are seldom well defined, and animal coloration patterns are rarely compared quantitatively with their respective backgrounds. Here we examine this issue in the Australian giant cuttlefish Sepia apama. We confine our analysis to the best-known and simplest image statistic, the correlation in intensity between neighboring pixels. Sepia apama can rapidly change their body patterns from assumed conspicuous signaling to assumed camouflage, thus providing an excellent and unique opportunity to investigate how such patterns differ in a single visual habitat. We describe the intensity variance and spatial frequency power spectra of these differing body patterns and compare these patterns with the backgrounds against which they are viewed. The measured image statistics of camouflaged animals closely resemble their backgrounds, while signaling animals differ significantly from their backgrounds. Our findings may provide the basis for a set of general rules for crypsis and signals. Furthermore, our methods may be widely applicable to the quantitative study of animal coloration.