Population Dynamics and Adaptive Sexual Strategies in a Brackish Water Crustacean, Gammarus duebeni

Naylor, Caroline; Adams, Jonathan; Greenwood, Paul J.

doi:10.2307/4920

Cited by 69 publications

(35 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Conover 1984, Conover & Heins 1987, the amphipod Gammarus duebeni (cf. Naylor et al 1988, McCabe & Dunn 1997) and now the copepod Pachypygus gibber (cf. Becheikh et al 1998 and the present study).…”

Section: Resultsmentioning

confidence: 99%

Environmental sex determination in a parasitic copepod: checking heterogeneity and unpredictability of the environment

Michaud

Meeûs²,

Renaud³

2004

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

For some organisms, sex is not fixed by genotype at conception but determined later by environmental conditions encountered during development (environmental sex determination, ESD). According to theoretical models, selection should favour ESD when the environment experienced by offspring is patchy and unpredictable and affects the relative fitness of males and females differentially. In a field study, we analysed the environmental heterogeneity displayed among individuals of the sea squirt Ciona intestinalis, a host for the copepod Pachypygus gibber, which is characterised by ESD. Consistent with theoretical predictions, environmental parameters that affect sex-specifically the fitness of the parasite (food and sexual partners) vary significantly in space and time. The spatial genetic structure of populations of P. gibber in the Thau lagoon, France, was investigated from allozyme data. No differentiation was found between distant populations, indicating that the larvae disperse intensively in the lagoon. Since their environment has been shown to be heterogeneous in space, and since the mothers cannot leave the host in which they developed, we conclude that both parent and offspring have little control over the quality of the environment the offspring enters. All the conditions are thus validated to support the adaptive nature of ESD in P. gibber.

show abstract

Section: Resultsmentioning

confidence: 99%

Environmental sex determination in a parasitic copepod: checking heterogeneity and unpredictability of the environment

Michaud

Meeûs²,

Renaud³

2004

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

show abstract

“…In nature, sex ratio fluctuations are frequently observed in amphipod populations, including E. marinus (Vlasblom, 1969), which seems to be regulated by some environmental factors such as temperature and photoperiod (Watt and Adams, 1993;Naylor et al, 1988;Dunn et al, 2005).…”

Section: Discussionmentioning

confidence: 99%

Intersexuality incidence, sex ratio fluctuations and intersex reproductive output as factors affecting the temporal variation of intersexed populations of the marine amphipod Echinogammarus marinus

Martins¹,

Ford²,

Fernandes³

2009

Marine Environmental Research

View full text Add to dashboard Cite

“…Several authors have reported seasonal changes in the size-speci®c fecundity of brackish amphipods (Sheader 1978(Sheader , 1983Fish and Mills 1979;Naylor et al 1988). Environmental factors such as temperature, salinity, photoperiod, oxygen concentration and food availability may be important in determining brood size (Kinne 1959;Vlasblom 1969;Fish 1975;Van Dolah and Bird 1980;Sheader 1983).…”

Section: Fecundity Intramarsupial Loss and Parental Carementioning

confidence: 99%

The amphipod Corophium multisetosum (Corophiidae) in Ria de Aveiro (NW Portugal). I. Life history and aspects of reproductive biology

2000

View full text Add to dashboard Cite

The population of Corophium multisetosum Stock, 1952 in AreaÄ o displayed a semiannual, iteroparous life history. Mean longevity was 6 mo, with the estimated life span longer for overwintering individuals born in autumn than for individuals born in spring. Length-frequency data indicated that the length increment per moult is probably higher in males than females; however females moulted more frequently and achieved a larger body size. Preliminary growth rates were 100 lm d )1 for juveniles and 19 to 29 lm d )1 for mature females, with the lower values occurring during the winter. It was estimated that under favourable conditions females may attain reproductive size and mature within 1 mo. Although incubating females were present all year round, recruitment occurred in spring, almost ceased during the summer, peaked in autumn, and decreased again during the winter. Extreme temperatures and very low salinities during winter and summer may have deterred breeding, while moderate temperatures (15 to 20°C) and salinities >1 psu in spring and autumn were apparently favourable for reproduction. The unfavourable summer conditions constrained breeding and synchronised the timing of reproduction. In late-autumn and during the winter, as temperature decreased and brooding time increased, synchrony was progressively lost. Brood size varied as a function of embryonic developmental stage, size of incubating females, and season. The life-history pattern and reproductive features of C. multisetosum in AreaÄ o are closely related to temperature and salinity; other environmental conditions such as oxygen content of the water and food availability may also be relevant.

show abstract

Population Dynamics and Adaptive Sexual Strategies in a Brackish Water Crustacean, Gammarus duebeni

Cited by 69 publications

References 9 publications

Environmental sex determination in a parasitic copepod: checking heterogeneity and unpredictability of the environment

Environmental sex determination in a parasitic copepod: checking heterogeneity and unpredictability of the environment

Intersexuality incidence, sex ratio fluctuations and intersex reproductive output as factors affecting the temporal variation of intersexed populations of the marine amphipod Echinogammarus marinus

The amphipod Corophium multisetosum (Corophiidae) in Ria de Aveiro (NW Portugal). I. Life history and aspects of reproductive biology

Contact Info

Product

Resources

About