Courting males often perform different behavioural displays that demonstrate aspects of their quality. Male fiddler crabs, Uca sp., are well known for their repetitive claw-waving display during courtship. However, in some species, males produce an additional signal by rapidly stridulating their claw, creating a 'drumming' vibrational signal through the substrate as a female approaches, and eve...

surprise that a lowlevel sensorimotor manipulation systematically influences the behavior in a task only implicitly evoking the notion of number magnitude. However, sensory and motor processes, which have originally evolved for basic interactions with the environment, are reportedly exploited during abstract cognition [15]. Intriguingly, as head turning can influence one’s spontaneous spatial e...

When females search for mates and their perceived risk of predation increases, they less often express preferences for males that use conspicuous courtship signals, relaxing sexual selection on production of these signals. Here, we report an apparent exception to this general pattern. Courting male fiddler crabs Uca beebei sometimes build pillars of mud at the openings to their burrows in which...

Positive plant–animal interactions are important in community ecology, but relatively little attention has been paid to their eVect on the production of mangroves, dominant halophytic trees in tropical coastal marshes. Here, the role of Wddler crab (Uca spp.) burrowing on the growth and production of the white mangrove, Laguncularia racemosa (<2 years old), was examined in a restored marsh in T...

A number of studies have suggested that mangrove forests and their faunal components may be pre-adapted to the impact of organic waste discharge, making them possible natural wastewater treatment wetlands. However, the results from recent research are contradictory. Some studies have shown that negative effects, sometimes subtle and difficult to observe, can be detected on specific biotic compo...

Melatonin (N-acetyl-5-methoxytryptamine) is an indolamine hormone produced by the pineal gland that works to regulate sleep/wake cycles and activity rhythms. The effects of melatonin in metabolism are far from understood. Melatonin was injected into the fiddler crab, Uea pugilator, to investigate the effects of melatonin on hemolymph glucose and lactate levels. Following injection at t=O, hemol...