Density-dependent competition and selection on immune function in genetic lizard morphs

Svensson, Erik I.; Sinervo, Barry; Comendant, Tosha

doi:10.1073/pnas.211071298

Cited by 180 publications

(229 citation statements)

References 37 publications

Supporting

Mentioning

211

Contrasting

Unclassified

Order By: Relevance

“…The two heritable female throat colour morphs in this species (orange and yellow) differ in their sensitivity to these changing social conditions and throat colour is genetically correlated with several fitness-related traits such as clutch size, egg mass (Sinervo et al 2000), and immune function (Svensson et al 2001). …”

Section: Female Sexual Polymorphisms In Natural Populationsmentioning

confidence: 99%

Female polymorphisms, sexual conflict and limits to speciation processes in animals

et al. 2007

View full text Add to dashboard Cite

Heritable and visually detectable polymorphisms, such as trophic polymorphisms, ecotypes, or colour morphs, have become classical model systems among ecological geneticists and evolutionary biologists. The relatively simple genetic basis of many such polymorphisms (one or a few loci) makes such species well-suited to study evolutionary processes in natural settings. More recently, polymorphic systems have become popular when studying the early stages of the speciation process and mechanisms facilitating or constraining the evolution of reproductive isolation. Although colour polymorphisms have been studied extensively in the past, we argue that they have been underutilized as model systems of constraints on speciation processes. Colouration traits may function as signalling characters in sexual selection contexts, and the maintenance of colour polymorphisms is often due to frequency-dependent selection.One important issue is why there are so few described cases of female polymorphisms. Here we present a synthetic overview of female sexual polymorphisms, drawing from our previous work on female colour polymorphisms in lizards and damselflies. We argue that female sexual polymorphisms have probably been overlooked in the past, since workers have mainly focused on male-male competition over mates and have not realized the ecological sources of genetic variation in female fitness. Recent experimental evolution studies on fruit flies (Drosophila melanogaster) have demonstrated significant heritable variation among female genotypes in the fitness costs of resistance or tolerance to male mating harassment. In addition, femalefemale competition over resources could also generate genetic variation in female fitness and promote the maintenance of female sexual polymorphisms. Female sexual polymorphisms could subsequently either be maintained as intrapopulational polymorphisms or provide the raw material for the formation of new species.

show abstract

Section: Female Sexual Polymorphisms In Natural Populationsmentioning

confidence: 99%

Female polymorphisms, sexual conflict and limits to speciation processes in animals

et al. 2007

View full text Add to dashboard Cite

show abstract

“…In contrast, at high densities, yellow-throated females, that have high levels of corticosterone, and that produce fewer, larger eggs, have a fitness advantage. Moreover, the female morphs were found to exhibit different fitness consequences with respect to immunocompetence responses associated with an increase in corticosterone (orange females had lower survivorship than yellow females) [204]. As a consequence of changing thermal conditions it is possible to imagine that given unpredictable climatic events, variation in the stress response between morphs initiates differences in rising corticosterone levels that may induce or exacerbate similar population cycles in a context-dependent fashion [205].…”

Section: Hormonally Mediated Maternal Effects On Dispersal and Populamentioning

confidence: 99%

Hormonally mediated maternal effects, individual strategy and global change

Meylan¹,

Miles

Clobert

2012

Phil. Trans. R. Soc. B

101

108

View full text Add to dashboard Cite

A challenge to ecologists and evolutionary biologists is predicting organismal responses to the anticipated changes to global ecosystems through climate change. Most evidence suggests that short-term global change may involve increasing occurrences of extreme events, therefore the immediate response of individuals will be determined by physiological capacities and life-history adaptations to cope with extreme environmental conditions. Here, we consider the role of hormones and maternal effects in determining the persistence of species in altered environments. Hormones, specifically steroids, are critical for patterning the behaviour and morphology of parents and their offspring. Hence, steroids have a pervasive influence on multiple aspects of the offspring phenotype over its lifespan. Stress hormones, e.g. glucocorticoids, modulate and perturb phenotypes both early in development and later into adulthood. Females exposed to abiotic stressors during reproduction may alter the phenotypes by manipulation of hormones to the embryos. Thus, hormone-mediated maternal effects, which generate phenotypic plasticity, may be one avenue for coping with global change. Variation in exposure to hormones during development influences both the propensity to disperse, which alters metapopulation dynamics, and population dynamics, by affecting either recruitment to the population or subsequent life-history characteristics of the offspring. We suggest that hormones may be an informative index to the potential for populations to adapt to changing environments.

show abstract

“…Examples of such traits that are correlated with colour come from studies of colour polymorphic insects and reptiles, in which differences between morphs in traits as diverse as developmental timing, fecundity, and disease resistance have been documented (Fahmy & Fahmy, 1959;Cook & Jacobs, 1983;Wilson et al, 2001;Svensson et al, 2001a;Svensson et al, 2001b;Svensson et al, 2002;True, 2003). When colour morphs are genetically correlated with other traits, as in the cases cited above, selection on such other traits can potentially result in a correlated response in morph frequencies.…”

Section: Introductionmentioning

confidence: 99%

Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly

Abbott¹,

Svensson²

2005

J Evolution Biol

View full text Add to dashboard Cite

Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly Ischnura elegans in the field and by raising larvae in a common laboratory environment. In the field, the three different female morphs emerged at different times. Among laboratory-raised families, we found evidence of a significant correlation between maternal morph and larval development time in both sexes. This suggests that the phenotypic correlation between morph and emergence time in the field has a parallel in a genetic correlation between maternal colour and offspring development time. Maternal colour morph frequencies could thus potentially change as correlated responses to selection on larval emergence dates. The similar genetic correlation in male offspring suggests that sex-limitation in this system is incomplete, which may lead to an ontogenetic sexual conflict between selection for early male emergence (protandry) and emergence times associated with maternal morph.

show abstract

Density-dependent competition and selection on immune function in genetic lizard morphs

Cited by 180 publications

References 37 publications

Female polymorphisms, sexual conflict and limits to speciation processes in animals

Female polymorphisms, sexual conflict and limits to speciation processes in animals

Hormonally mediated maternal effects, individual strategy and global change

Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly

Contact Info

Product

Resources

About