We describe the first robot designed to emulate specific perceptual and motor capabilities of the fiddler crab. An omnidirectional robot platform uses onboard computation to process images from a 360◦ camera view, filtering it through a biological model of the crab’s ommatidia layout, extracting potential ‘predator’ cues, and executing an evasion response that also depends on contextual informa...

Fiddler crabs inhabit intertidal sand- and mudflats, where they live in dense colonies and are active on the surface during low tide. They exhibit a rich behavioural repertoire, with frequent interactions between animals in the context of territorial and mating activities. Male fiddler crabs have one massively enlarged and conspicuously coloured claw, which they use in waving displays and in fi...

8 The polarisation of light is used by many species of cephalopods and crustaceans to discriminate 9 objects or to communicate. Most visual systems with this ability, such as that of the fiddler crab, 10 include receptors with photopigments that are oriented horizontally and vertically relative to the 11 outside world. Photoreceptors in such an orthogonal array are maximally sensitive to polari...

We are constantly surprised by the ability of relatively simple animals to perform precise visually guided movements within complex visual scenes, often using eyes with limited resolution. Exceptional examples include the capture of airborne prey by dragonflies, the learning flights of bees and wasps, and the tracking of conspecifics by crabs on intertidal mudflats. Most studies have focused on...

The fiddler crabs, Uca lactea, which live on intertidal mudflats, exhibit a remarkable ability to return to its burrow. It has been reported that the species usually use path integration, an ideothetic mechanism for short-range homing. During the mating season, however, the accumulation error of the process increases due to vigorous courtship movement. To compensate for this, most courting male...

Salt marshes in northern Barataria Bay, Louisiana, USA were oiled, sometimes heavily, in the aftermath of the Deepwater Horizon oil spill. Previous studies indicate that fiddler crabs (in the genus Uca) and the salt marsh periwinkle (Littoraria irrorata) were negatively impacted in the short term by the spill. Here, we detail longer-term effects and recovery from moderate and heavy oiling over ...

The polarisation of light is used by many species of cephalopods and crustaceans to discriminate objects or to communicate. Most visual systems with this ability, such as that of the fiddler crab, include receptors with photopigments that are oriented horizontally and vertically relative to the outside world. Photoreceptors in such an orthogonal array are maximally sensitive to polarised light ...

Fiddler crabs have compound eyes that are structurally fairly well understood. However, there has been much debate regarding their spectral sensitivity and capacity to enable colour discrimination. We examined the visual pigments of two North-American species (Uca pugnax and U. pugilator), one species from the Indo-West Pacific (U. vomeris) and the only Eastern-Atlantic species (U. tangeri) of ...

Cyber-taxonomy of name usage has focused primarily on producing authoritative lists of names or cross-linking names and data across disparate databases. A feature missing from much of this work is the recording and analysis of the context in which a name was used--context which can be critical for understanding not only what name an author used, but to which currently recognized species they ac...