Browse
Submit Data
Databases
API
Help

Dataset Information

17 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Not what it looks like: mate-searching behaviour, mate preferences and clutch production in wandering and territory-holding female fiddler crabs.

ABSTRACT: Risks inherent in mate-searching have led to the assumption that females moving sequentially through populations of courting males are sexually receptive, but this may not be true. We examined two types of fiddler crab females: wanderers moving through the population of courting males and residents that were occupying and defending their own territories. Sometimes residents leave territories to look for new burrows and we simulated this by displacing wanderers and residents and observing their behaviour while wandering. We predicted that the displaced wanderers would exhibit more mate-searching behaviours than resident females. However, wandering and resident females behaved nearly identically, displaying mate-searching behaviours and demonstrating matching mate preferences. Also, males behaved the same way towards both female types and similar proportions of wanderers and residents stayed in a male's burrow to mate. But more wanderers than residents produced egg clutches when choosing a burrow containing a male, suggesting females should be categorized as receptive and non-receptive. Visiting and rejecting several males is not the defining feature of female mate choice. Moving across the mudflat by approaching and leaving a succession of burrows (mostly occupied by males) is an adaptive anti-predator behaviour that is useful in the contexts of mate-searching and territory-searching.

SUBMITTER: Peso M

PROVIDER: S-EPMC5108965 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Robotic crabs reveal that female fiddler crabs are sensitive to changes in male display rate.

Project description:Males often produce dynamic, repetitive courtship displays that can be demanding to perform and might advertise male quality to females. A key feature of demanding displays is that they can change in intensity: escalating as a male increases his signalling effort, but de-escalating as a signaller becomes fatigued. Here, we investigated whether female fiddler crabs, Uca mjoebergi, are sensitive to changes in male courtship wave rate. We performed playback experiments using robotic male crabs that had the same mean wave rate, but either escalated, de-escalated or remained constant. Females demonstrated a strong preference for escalating robots, but showed mixed responses to robots that de-escalated ('fast' to 'slow') compared to those that waved at a constant 'medium' rate. These findings demonstrate that females can discern changes in male display rate, and prefer males that escalate, but that females are also sensitive to past display rates indicative of prior vigour.

| S-EPMC5803598 | biostudies-literature

Multimodal communication in courting fiddler crabs reveals male performance capacities.

Project description: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 even continue to drum once inside their burrow. Here, we show that the switch from waving to drumming might provide additional information to the female about the quality of a male, and the properties of his burrow (multiple message hypothesis). Across males there was, however, a strong positive relationship between aspects of their waving and drumming displays, suggesting that drumming adheres to some predictions of the redundant signal hypothesis for multimodal signalling. In field experiments, we show that recent courtship is associated with a significant reduction in male sprint speed, which is commensurate with an oxygen debt. Even so, males that wave and drum more vigorously than their counterparts have a higher sprint speed. Drumming appears to be an energetically costly multimodal display of quality that females should attend to when making their mate choice decisions.

| S-EPMC5383853 | biostudies-literature

Does male reproductive effort increase with age? Courtship in fiddler crabs.

Project description:Theory suggests that reproductive effort generally increases with age, but life-history models indicate that other outcomes are possible. Empirical data are needed to quantify variation in actual age-dependence. Data are readily attainable for females (e.g. clutch per egg size), but not for males (e.g. courtship effort). To quantify male effort one must: (i) experimentally control for potential age-dependent changes in female presence; and, crucially, (ii) distinguish between the likelihood of courtship being initiated, the display rate, and the total time invested in courting before stopping ('courtship persistence'). We provide a simple experimental protocol, suitable for many taxa, to illustrate how to obtain this information. We studied courtship waving by male fiddler crabs, Uca annulipes. Given indeterminate growth, body size is correlated with age. Larger males were more likely to wave at females and waved more persistently. They did not, however, have a higher courtship rate (waves per second). A known female preference for males with higher display rates explains why, once waving is initiated, all males display at the same rate.

| S-EPMC3639757 | biostudies-literature

Phylogenetic patterns and the adaptive evolution of osmoregulation in fiddler crabs (Brachyura, Uca).

Project description:Salinity is the primary driver of osmoregulatory evolution in decapods, and may have influenced their diversification into different osmotic niches. In semi-terrestrial crabs, hyper-osmoregulatory ability favors sojourns into burrows and dilute media, and provides a safeguard against hemolymph dilution; hypo-osmoregulatory ability underlies emersion capability and a life more removed from water sources. However, most comparative studies have neglected the roles of the phylogenetic and environmental components of inter-specific physiological variation, hindering evaluation of phylogenetic patterns and the adaptive nature of osmoregulatory evolution. Semi-terrestrial fiddler crabs (Uca) inhabit fresh to hyper-saline waters, with species from the Americas occupying higher intertidal habitats than Indo-west Pacific species mainly found in the low intertidal zone. Here, we characterize numerous osmoregulatory traits in all ten fiddler crabs found along the Atlantic coast of Brazil, and we employ phylogenetic comparative methods using 24 species to test for: (i) similarities of osmoregulatory ability among closely related species; (ii) salinity as a driver of osmoregulatory evolution; (iii) correlation between salt uptake and secretion; and (iv) adaptive peaks in osmoregulatory ability in the high intertidal American lineages. Our findings reveal that osmoregulation in Uca exhibits strong phylogenetic patterns in salt uptake traits. Salinity does not correlate with hyper/hypo-regulatory abilities, but drives hemolymph osmolality at ambient salinities. Osmoregulatory traits have evolved towards three adaptive peaks, revealing a significant contribution of hyper/hypo-regulatory ability in the American clades. Thus, during the evolutionary history of fiddler crabs, salinity has driven some of the osmoregulatory transformations that underpin habitat diversification, although others are apparently constrained phylogenetically.

| S-EPMC5300755 | biostudies-literature

Interaction between path integration and visual orientation during the homing run of fiddler crabs.

Project description:Foraging fiddler crabs form a strict spatial relationship between their current positions and burrows, allowing them to run directly back to their burrows when startled even without visual contacts. Path integration (PI), the underlying mechanism, is a universal navigation strategy through which animals continuously integrate directions and distances of their movements. However, we report that fiddler crabs also use visual orientation during homing runs using burrow entrances as cues, with the prioritised mechanism (i.e. PI or visual) determined by the distance (which has a threshold value) between the goal, indicated by PI, and the visual cue. When we imposed homing errors using fake entrances (visual cue) and masking their true burrows (goal of PI), we found that frightened fiddler crabs initially ran towards the true burrow following PI, then altered their behaviour depending on the distance between the fake entrance and masked true burrow: if the distance was large, they kept running until they reached the true burrow, ignoring the visual cue; however, if the distance was small, they altered the homing path and ran until they reached the fake entrance. This suggests that PI and visual mechanism in fiddler crabs are mutually mediated to achieve their homing behaviour.

| S-EPMC5627127 | biostudies-literature

Reproducing on time when temperature varies: shifts in the timing of courtship by fiddler crabs.

Project description:Many species reproduce when conditions are most favorable for the survival of young. Numerous intertidal fish and invertebrates release eggs or larvae during semilunar, large amplitude, nocturnal tides when these early life stages are best able to escape predation by fish that feed near the shore during the day. Remarkably, some species, including the fiddler crabs Uca terpsichores and Uca deichmanni, maintain this timing throughout the year as temperature, and thus the rate of embryonic development, vary. The mechanisms that allow such precision in the timing of the production of young are poorly known. A preliminary study suggested that when temperature decreases, U. terpsichores mate earlier in the tidal amplitude cycle such that larvae are released at the appropriate time. We tested this idea by studying the timing of courtship in U. terpsichores and U. deichmanni as temperature varied annually during two years, at 5 locations that differed in the temperature of the sediment where females incubate their eggs. Uca terpsichores courted earlier at locations where sediment temperature declined seasonally but not where sediment temperature remained elevated throughout the year. In contrast, clear shifts in courtship timing were not observed for U. deichmanni despite variation in sediment temperature. We discuss other mechanisms by which this species may maintain reproductive timing. These two species are likely to be affected differently by changes in the frequency and intensity of cold periods that are expected to accompany climate change.

| S-EPMC4022618 | biostudies-literature

An illustrated key to the fiddler crabs (Crustacea, Decapoda, Ocypodidae) from the Atlantic coast of Brazil.

Project description:Fiddler crabs are one of the most notable animal groups in Brazilian estuarine environments, due to their high density and characteristic waving of males. An illustrated key to the ten species recorded as far in the country is provided using only clearly visible characters of males. Furthermore, additional recognition characters, information about geographic distribution and biology of each species are presented. Most examined crabs were collected in Guaratuba Bay, southern Brazil.

| S-EPMC7324410 | biostudies-literature

A disparity between locomotor economy and territory-holding ability in male house mice.

Project description:Both economical locomotion and physical fighting are important performance traits to many species because of their direct influence on components of Darwinian fitness. Locomotion represents a substantial portion of the total daily energy budget of many animals. Fighting performance often determines individual reproductive fitness through the means of resource control, social dominance and access to mates. However, phenotypic traits that improve either locomotor economy or fighting ability may diminish performance in the other. Here, we tested for a predicted disparity between locomotor economy and competitive ability in wild-derived house mice (Mus musculus). We used 8 week social competition trials in semi-natural enclosures to directly measure male competitive ability through territorial control and female occupancy within territories. We also measured oxygen consumption during locomotion for each mouse using running trials in an enclosed treadmill and open-flow respirometry. Our results show that territory-holding males have higher absolute and mass-specific oxygen consumption when running (i.e. reduced locomotor economy) compared with males that do not control territories. This relationship was present both before and after 8 week competition trials in semi-natural enclosures. This disparity between physical competitive ability and economical locomotion may impose viability costs on males in species for which competition over mates is common and may constrain the evolution of behavioral and phenotypic diversity, particularly in natural settings with environmental and resource variability.

| S-EPMC5536892 | biostudies-literature

Sensory regulation of C. elegans male mate-searching behavior.

Project description:How do animals integrate internal drives and external environmental cues to coordinate behaviors? We address this question by studying mate-searching behavior in C. elegans. C. elegans males explore their environment in search of mates (hermaphrodites) and will leave food if mating partners are absent. However, when mates and food coincide, male exploratory behavior is suppressed and males are retained on the food source. We show that the drive to explore is stimulated by male-specific neurons in the tail, the ray neurons. Periodic contact with the hermaphrodite detected through ray neurons changes the male's behavior during periods of no contact and prevents the male from leaving the food source. The hermaphrodite signal is conveyed by male-specific interneurons that are postsynaptic to the rays and that send processes to the major integrative center in the head. This study identifies key parts of the neural circuit that regulates a sexual appetitive behavior in C. elegans.

| S-EPMC2652568 | biostudies-literature

Claw Waving for Sex: An Inquiry-Based Lab to Teach Sexual Dimorphism and Behavior in Fiddler Crabs.

Project description: Not available

| S-EPMC6022774 | biostudies-literature