Consuming Costly Prey: Optimal Foraging and the Role of Compensatory Growth

Frontiers in Ecology and Evolution, Год журнала: 2021, Номер 8

Опубликована: Март 18, 2021

Some prey are exceptionally difficult to digest, and yet even non-specialized animals may consume them—why? Durophagy, the consumption of hard-shelled prey, is thought require special adaptations for crushing or digesting hard shells avoid many potential costs this type. But lacking specializations nevertheless include hard-bodied in their diets. We describe several non-mutually exclusive adaptive mechanisms that could explain such a pattern, point optimal foraging compensatory growth as potentially having widespread importance explaining costly-prey consumption. first conducted literature survey quantify regularity with which teleost fishes prey: stomach-content data from 325 fish species spanning 82 families (57,233 stomach samples) demonstrated comprise ~75% total exhibiting durophagy, commonly consuming at low moderate levels (~10–40% much specialists). then performed diet assess frequency molluscivory across native latitudinal range small livebearing fish, Gambusia holbrooki , durophagy specializations. Molluscivory was regionally widespread, entire (>14° latitude). Third, we tested higher under conditions intraspecific resource competition Bahamian mosquitofish ( spp.). Examining over 5,300 individuals, found more common populations population density, suggesting food limitation important eliciting molluscivory. Finally, experimentally G. whether reduces rate follows period gastropods results significantly reduced rate, but following prior snail can quickly mitigate costs. Our suggest phenomenon be partially explained by its relative benefits when few alternative options exist, combined alleviates temporary

Язык: Английский

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Rapid, parallel evolution of field mustard ( Brassica rapa ) under experimental drought

Evolution, Год журнала: 2021, Номер 76(2), С. 262 - 274

Опубликована: Дек. 8, 2021

Climate change is driving evolutionary and plastic responses in populations, but predicting these remains challenging. Studies that combine experimental evolution with ancestor-descendant comparisons allow assessment of the causes, parallelism, adaptive nature responses, although such studies remain rare, particularly a climate context. Here, we created populations Brassica rapa derived from same natural population exposed replicated to drought or watered conditions for four generations. We then grew ancestors descendants concurrently, following resurrection approach. Experimental under showed rapid earlier flowering time increased specific leaf area, consistent escape strategy observations populations. Evolutionary shifts followed direction selection fitness drought, indicative evolution. Evolution also occurred largely parallel among replicate Further, traits phenotypic plasticity effect size varied. Our results demonstrate suggesting strong, may be predictable. Broadly, our study demonstrates utility combining approach investigate change.

Язык: Английский

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Population history and the selective landscape shape patterns of osmoregulatory trait divergence in tidal marsh Savannah sparrows (Passerculus sandwichensis)

Evolution, Год журнала: 2019, Номер 74(1), С. 57 - 72

Опубликована: Ноя. 21, 2019

A persistent challenge in making associations between phenotypic and environmental variation is understanding how ecological factors demographic history interact to shape adaptive outcomes. Evaluating the degree which conspecific populations exposed similar pressures respond parallel provides a powerful framework for addressing this challenge. We took comparative approach with multiple of Savannah sparrows (Passerculus sandwichensis) found tidal marshes along Pacific coast North America. The high salinities characterizing select increased osmoregulatory performance salinity tolerance. collected data on physiological traits associated from 10 marsh three freshwater-adapted interior evaluate divergence across populations. All showed differences magnitude divergence, but only total evaporative water loss (TEWL) direction divergence. drivers these both varied among traits. For kidney morphology TEWL, patterns were best explained by immigration rate Maximum temperature was predictor urine excretion ability, gene flow contributed plasma osmolality. Finally, analysis multitrait indicated that population genetic structure, whereas differences. Together results show influences demography selective landscape can manifest themselves differently functionally integrated

Язык: Английский

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Effects of predation risk on egg steroid profiles across multiple populations of threespine stickleback

Scientific Reports, Год журнала: 2020, Номер 10(1)

Опубликована: Март 23, 2020

Predation often has consistent effects on prey behavior and morphology, but whether the physiological mechanisms underlying these show similarly patterns across different populations remains an open question. In vertebrates, predation risk activates hypothalamic-pituitary-adrenal (HPA) axis, there is growing evidence that activation of maternal HPA axis can have intergenerational consequences via, for example, maternally-derived steroids in eggs. Here, we investigated how affects a suite threespine stickleback eggs nine Alaskan lakes vary predatory trout are absent, native, or been stocked within last 25 years. Using liquid chromatography coupled with mass spectroscopy (LC-MS/MS), detected 20 unfertilized Factor analysis suggests covary steroid classes (i.e. glucocorticoids, progestogens, sex steroids), emphasizing modularity interconnectedness endocrine response. Surprisingly, egg profiles were not significantly associated predator regime, although they more variable when predators absent compared to present, either native trout. Despite being most abundant steroid, cortisol was consistently regime. Thus, while affect adults, including mothers, link between stress embryonic development complex than simple one-to-one relationship population-level experienced by mothers transfer their

Язык: Английский

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Predation shapes behavioral lateralization: insights from an adaptive radiation of livebearing fish

Behavioral Ecology, Год журнала: 2021, Номер 32(6), С. 1321 - 1329

Опубликована: Авг. 5, 2021

Abstract Hemispheric brain lateralization can drive the expression of behavioral asymmetry, or laterality, which varies notably both within and among species. To explain these left–right asymmetries in animals, predator-mediated selection is often invoked. Recent studies have revealed that a relatively high degree correlates positively with traits known to confer survival benefits against predators, including escape performance, multitasking abilities, group coordination. Yet, we still know comparatively little about 1) how consistently predators shape lateralization, 2) importance sex-specific variation, 3) heritable. Here, take advantage model system radiation Bahamas mosquitofish (Gambusia hubbsi) measure hundreds wild fish originating from multiple blue holes differ natural predation pressure. Moreover, estimated heritability this trait using laboratory-born one focal population. We found but not particular direction (left right) differed significantly across low risk environments. Fish high-predation environments were more strongly lateralized, especially females. further confirmed genetic basis species, significant additive variation population examined. Our results reveal represents key ecological factor has likely shaped origin maintenance widespread phenomenon, even potentially explaining some patterns laterality recently described animals.

Язык: Английский

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