Author: Charlie Arreza YparraguirrePublisher:
ISBN:
Category : Fiddler crabs
Languages : en
Pages : 248
Book Description
Sexual Selection in the Fiddler Crab, Uca Vocans (Linnaeus)
Author: Charlie Arreza YparraguirrePublisher:
ISBN:
Category : Fiddler crabs
Languages : en
Pages : 248
Book Description
The Effects of Sexual Selection on the Interaction of Foraging and Social Behavior in the Gulf Coast Fiddler Crab, Uca Panacea
Author: Halina Elizabeth CaravelloPublisher:
ISBN:
Category : Fiddler crabs
Languages : en
Pages : 184
Book Description
Reproductive Success and Factors Effecting Sexual Selection in a Fiddler Crab, Uca Mjoebergi
Author: Huon ClarkPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Producing offspring is the most important aspect of an animal's life. Reproductive success is the cornerstone of evolution, but successful mating is a complex process that we are only starting to understand. This thesis examines five aspects of reproductive success in a fiddler crab, Uca mjoebergi. This is an ideal study species since the crabs are tractable, abundant and amenable to manipulation. In the first chapter, I examine the natural mate-searching behaviour of females and show, for the first time in any species, that there is a mosaic of preferences: females prefer males of different sizes depending on where they are in the tidal zone, and when they are mate-searching in the tidal cycle. This level of complexity in female preferences can partly explain the 'lek paradox'.In the second chapter, I examine assortative mating and show that there is a strong correlation between the size of males and females in mated pairs. I show that neither mate availability nor mating constraints can explain the pattern. Since both males and females preferentially mate with larger partners, sexual selection explains the high level of size-assortative mating. In chapter three, I revisit earlier work on this species showing that claw loss and subsequent regeneration strongly disadvantages males in terms of reproductive success. By substantially increasing the sample size, I show that males with regenerated claws are not at a mating disadvantage. This study highlights the importance of large sample sizes in behavioural studies. In chapter four, I examine the effect of temperature on mating success. Males can live in the sun or shade. There are advantages to living in the shade: males can be active for longer periods and they are less likely to dehydrate or overheat. Females that chose to mate with males living in the shade, however, would incubate their eggs at approximately 3'C lower than females incubating in sunny territories. I show that this difference in temperature does not affect the timing of crucial reproductive events and does not prevent the females from releasing their fully-formed larvae at the optimal time.In chapter five, I examine the potential consequence of habitat loss and subsequent overlap between species distributions. We can already observe this: a larger, lower-living fiddler crab is invading the habitat of Uca mjoebergi, increasing the competition between these species. I show that the disadvantages experienced by male U. mjoebergi from having a heterospecific neighbour is not necessarily as severe as common sense may suggest.
Conflict Over Male Searching in Fiddler Crabs
Author: Catherine Elaine deRiveraPublisher:
ISBN:
Category :
Languages : en
Pages : 314
Book Description
Reproductive Success and Factors Affecting Sexual Selection in a Fiddler Crab, Uca Mjoebergi
Author: Huon Lyndon ClarkPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Producing offspring is the most important aspect of an animal's life. Reproductive success is the cornerstone of evolution, but successful mating is a complex process that we are only starting to understand. This thesis examines five aspects of reproductive success in a fiddler crab, Uca mjoebergi. This is an ideal study species since the crabs are tractable, abundant and amenable to manipulation. In the first chapter, I examine the natural mate-searching behaviour of females and show, for the first time in any species, that there is a mosaic of preferences: females prefer males of different sizes depending on where they are in the tidal zone, and when they are mate-searching in the tidal cycle. This level of complexity in female preferences can partly explain the 'lek paradox'. In the second chapter, I examine assortative mating and show that there is a strong correlation between the size of males and females in mated pairs. I show that neither mate availability nor mating constraints can explain the pattern. Since both males and females preferentially mate with larger partners, sexual selection explains the high level of size-assortative mating. In chapter three, I revisit earlier work on this species showing that claw loss and subsequent regeneration strongly disadvantages males in terms of reproductive success. By substantially increasing the sample size, I show that males with regenerated claws are not at a mating disadvantage. This study highlights the importance of large sample sizes in behavioural studies. In chapter four, I examine the effect of temperature on mating success. Males can live in the sun or shade. There are advantages to living in the shade: males can be active for longer periods and they are less likely to dehydrate or overheat. Females that chose to mate with males living in the shade, however, would incubate their eggs at approximately 3°C lower than females incubating in sunny territories. I show that this difference in temperature does not affect the timing of crucial reproductive events and does not prevent the females from releasing their fully-formed larvae at the optimal time. In chapter five, I examine the potential consequence of habitat loss and subsequent overlap between species distributions. We can already observe this: a larger, lower-living fiddler crab is invading the habitat of Uca mjoebergi, increasing the competition between these species. I show that the disadvantages experienced by male U. mjoebergi from having a heterospecific neighbour is not necessarily as severe as common sense may suggest.
Selection for Sexually Dimorphic Traits and Signal Diversity in Fiddler Crabs
Author: Daniela PerezPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The evolution of diverse sexual signals and traits in animals is a promising yet challenging field in behavioural ecology. Sexual features are under the influence of a multitude, and often cryptic, mechanisms. In addition, the composition and strength of selection varies for each study species. Fiddler crabs are ideal subjects for investigating the evolution of diverse sexual traits. Males possess one sexually dimorphic enlarged claw. The structure is used as a weapon in conflicts over territory and signaled in the form of wave displays as courtship to females and warning to intruders. The displays are diverse on the interspecific level, characterized by species-specific movement patterns. In this thesis, I explore the forces behind the evolution of sexually dimorphic claws and the great diversification of fiddler crab signals. In the first two chapters of my thesis I search for a clearer understanding of sexual selection in shaping the species-specific diversity of wave displays in fiddler crabs. First, I investigate if wave displays are cues for species identity in sympatric populations. I use robotic crabs in my experiments and verify that females are able to choose the conspecific over a heterospecific wave movement. In chapter II, I direct my focus to female natural choices and identify their preferences on wave displays and claw size. This final approach allows me to reveal other selective mechanisms, such as constraints from natural selection in male signaling effort. In the second part of my thesis, I expand my approach to the level of social context and its effects on fiddler crab sexual traits. In chapter III, I look into the laterality of the sexually dimorphic claw and examine the different fight endurances when opponents are same- or different-handed. I point out how distinct handedness ratios in fiddler crab populations set contrasting selective pressures in male-male coalitions. In chapter IV, I explore differential social situations in the production of wave signals, and take a step further to explore the social contexts that stimulate the emergence of a rare signal phenomenon, the synchronous waving. Finally, in chapter V, I look into signal diversity from a wider perspective by applying comparative approach to understand the evolution of the wave displays. I gather structural and temporal information of the wave displays of 28 species to predict the likelihood and evolutionary paths of presenting waves in synchrony. Lastly, I indicate how the phenomenon may stem from the particularities of a species mating systems and ecological adaptations.
Costs of Sexual Selection in the Sand Fiddler Crab, Uca Pugilator
Author: Sexual Selection and the Evolution of Exaggerated Traits in Fiddler Crabs
Author: Ofer EitanPublisher:
ISBN:
Category : Fiddler crabs
Languages : en
Pages : 82
Book Description
The Mating System of the Sand Fiddler Crab, Uca Pugilator
Author: John Harold ChristyPublisher:
ISBN:
Category : Courtship in animals
Languages : en
Pages : 686
Book Description
The Life of Fiddler Crabs
Author: Richard Norman Crothers MilnerPublisher:
ISBN:
Category : Animal communication
Languages : en
Pages : 398
Book Description
From violence to romance, fiddler crabs are an ideal study system to explore questions and predictions important to behavioural ecology and sexual selection. Fiddler crabs of the genus Uca are members of the Ocypodid family of brachyuran crabs. These highly social crabs occur in dense mixed sex colonies, and display pronounced sexual dimorphism. Males are endowed with one greatly enlarged claw that is used during courtship, as well as a weapon during aggressive interactions. Females lack this claw and instead have two small feeding claws. Fiddler crabs are highly territorial and display both male contest competition and female mate choice. The following nine chapters of this thesis explore the behavioural ecology of fiddler crabs.