Thermal adaptation and phenotypic plasticity in a warming world: Insights from common garden experiments on Alaskan sockeye salmon

Understanding how populations adapt to heterogeneous thermal regimes is essential for comprehending how latitudinal gradients in species diversification are formed, and how taxa will respond to ongoing climate change. Adaptation can occur by innate genetic factors, by phenotypic plasticity, or by a combination of both mechanisms. Yet, the relative contribution of such mechanisms to large-scale latitudinal gradients of thermal tolerance across conspecific populations remains unclear. We examine thermal performance in 11 populations of the intertidal copepod Tigriopus californicus , ranging from Baja California Sur (Mexico) to British Columbia (Canada). Common garden experiments show that survivorship to acute heat-stress differs between populations (by up to 3.8°C in LD 50 values), reflecting a strong genetic thermal adaptation. Using a split-brood experiment with two rearing temperatures, we also show that developmental phenotypic plasticity is beneficial to thermal tolerance (by up to 1.3°C), and that this effect differs across populations. Although genetic divergence in heat tolerance strongly correlates with latitude and temperature, differences in the plastic response do not. In the context of climate warming, our results confirm the general prediction that low-latitude populations are most susceptible to local extinction because genetic adaptation has placed physiological limits closer to current environmental maxima, but our results also contradict the prediction that phenotypic plasticity is constrained at lower latitudes.

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Complex interactions between local adaptation, phenotypic plasticity and sex affect vulnerability to warming in a widespread marine copepod

Royal Society Open Science ◽

10.1098/rsos.182115 ◽

2019 ◽

Vol 6 (3) ◽

pp. 182115 ◽

Cited By ~ 3

Author(s):

Matthew Sasaki ◽

Sydney Hedberg ◽

Kailin Richardson ◽

Hans G. Dam

Keyword(s):

Phenotypic Plasticity ◽

Local Adaptation ◽

Thermal Performance ◽

Thermal Tolerance ◽

Population Decline ◽

Common Garden ◽

Population Level ◽

Marine Copepod ◽

Complex Interactions ◽

Common Garden Experiments

Predicting the response of populations to climate change requires an understanding of how various factors affect thermal performance. Genetic differentiation is well known to affect thermal performance, but the effects of sex and developmental phenotypic plasticity often go uncharacterized. We used common garden experiments to test for effects of local adaptation, developmental phenotypic plasticity and individual sex on thermal performance of the ubiquitous copepod,Acartia tonsa(Calanoida, Crustacea) from two populations strongly differing in thermal regimes (Florida and Connecticut, USA). Females had higher thermal tolerance than males in both populations, while the Florida population had higher thermal tolerance compared with the Connecticut population. An effect of developmental phenotypic plasticity on thermal tolerance was observed only in the Connecticut population. Our results show clearly that thermal performance is affected by complex interactions of the three tested variables. Ignoring sex-specific differences in thermal performance may result in a severe underestimation of population-level impacts of warming because of population decline due to sperm limitation. Furthermore, despite having a higher thermal tolerance, low-latitude populations may be more vulnerable to warming as they lack the ability to respond to increases in temperature through phenotypic plasticity.

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Phenotypic Plasticity in the Invasion of Crofton Weed (Eupatorium adenophorum) in China

Weed Science ◽

10.1614/ws-d-11-00198.1 ◽

2012 ◽

Vol 60 (3) ◽

pp. 431-439 ◽

Cited By ~ 13

Author(s):

Yujie Zhao ◽

Xuejun Yang ◽

Xinqiang Xi ◽

Xianming Gao ◽

Shucun Sun

Keyword(s):

Genetic Variation ◽

Phenotypic Plasticity ◽

Leaf Area ◽

Functional Traits ◽

Common Garden ◽

Similar Reaction ◽

Crofton Weed ◽

Wide Range ◽

Population Origin ◽

Common Garden Experiments

Phenotypic plasticity and rapid evolution are two important strategies by which invasive species adapt to a wide range of environments and consequently are closely associated with plant invasion. To test their importance in invasion success of Crofton weed, we examined the phenotypic response and genetic variation of the weed by conducting a field investigation, common garden experiments, and intersimple sequence repeat (ISSR) marker analysis on 16 populations in China. Molecular markers revealed low genetic variation among and within the sampled populations. There were significant differences in leaf area (LA), specific leaf area (SLA), and seed number (SN) among field populations, and plasticity index (PIv) for LA, SLA, and SN were 0.62, 0.46 and 0.85, respectively. Regression analyses revealed a significant quadratic effect of latitude of population origin on LA, SLA, and SN based on field data but not on traits in the common garden experiments (greenhouse and open air). Plants from different populations showed similar reaction norms across the two common gardens for functional traits. LA, SLA, aboveground biomass, plant height at harvest, first flowering day, and life span were higher in the greenhouse than in the open-air garden, whereas SN was lower. Growth conditions (greenhouse vs. open air) and the interactions between growth condition and population origin significantly affect plant traits. The combined evidence suggests high phenotypic plasticity but low genetically based variation for functional traits of Crofton weed in the invaded range. Therefore, we suggest that phenotypic plasticity is the primary strategy for Crofton weed as an aggressive invader that can adapt to diverse environments in China.

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Complex interactions between local adaptation, plasticity, and sex affect vulnerability to warming in a widespread marine copepod

10.1101/423624 ◽

2018 ◽

Author(s):

Matthew Sasaki ◽

Sydney Hedberg ◽

Kailin Richardson ◽

Hans G. Dam

Keyword(s):

Phenotypic Plasticity ◽

Local Adaptation ◽

Thermal Performance ◽

Thermal Tolerance ◽

Population Decline ◽

Common Garden ◽

Population Level ◽

Marine Copepod ◽

Complex Interactions ◽

Common Garden Experiments

AbstractPredicting the response of populations to climate change requires knowledge of thermal performance. Genetic differentiation and phenotypic plasticity affect thermal performance, but the effects of sex and developmental temperatures often go uncharacterized. We used common garden experiments to test for effects of local adaptation, developmental phenotypic plasticity, and individual sex on thermal performance of the ubiquitous copepod, Acartia tonsa. Females had higher thermal tolerance than males in both populations, while the Florida population had higher thermal tolerance compared to the Connecticut population. An effect of developmental phenotypic plasticity on thermal tolerance was observed only in the Connecticut population. Ignoring sex-specific differences may result in a severe underestimation of population-level impacts of warming (i.e. - population decline due to sperm limitation). Further, despite having a higher thermal tolerance, southern populations may be more vulnerable to warming as they lack the ability to respond to increases in temperature through phenotypic plasticity.

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Sex ratio and life history traits at reaching sexual maturity in the dioecious shrub Fuchsia parviflora: field and common garden experiments

Journal of Tropical Ecology ◽

10.1017/s0266467421000043 ◽

2021 ◽

pp. 1-6

Author(s):

Jessica S. Ambriz ◽

Clementina González ◽

Eduardo Cuevas

Keyword(s):

Natural Population ◽

Sexual Maturity ◽

Sex Ratios ◽

Natural Populations ◽

Common Garden ◽

Common Garden Experiment ◽

Trade Offs ◽

Reproductive Biomass ◽

Common Garden Experiments ◽

Growth And Reproduction

Abstract Fuchsia parviflora is a dioecious shrub that depends on biotic pollination for reproduction. Previous studies suggest that the male plants produce more flowers, and male-biased sex ratios have been found in some natural populations. To assess whether the biased sex ratios found between genders in natural populations are present at the point at which plants reach sexual maturity, and to identify possible trade-offs between growth and reproduction, we performed a common garden experiment. Finally, to complement the information of the common garden experiment, we estimated the reproductive biomass allocation between genders in one natural population. Sex ratios at reaching sexual maturity in F. parviflora did not differ from 0.5, except in one population, which was the smallest seedling population. We found no differences between genders in terms of the probability of germination or flowering. When flowering began, female plants were taller than males and the tallest plants of both genders required more time to reach sexual maturity. Males produced significantly more flowers than females, and the number of flowers increased with plant height in both genders. Finally, in the natural population studied, the investment in reproductive biomass was seven-fold greater in female plants than in male plants. Our results showed no evidence of possible trade-offs between growth and reproduction. Despite the fact that female plants invest more in reproductive biomass, they were taller than the males after flowering, possibly at the expense of herbivory defence.

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Variation in regrowth ability in relation to land-use intensity in three common grassland herbs

Journal of Plant Ecology ◽

10.1093/jpe/rtab001 ◽

2021 ◽

Author(s):

Anna Kirschbaum ◽

Oliver Bossdorf ◽

J F Scheepens

Keyword(s):

Land Use ◽

Phenotypic Plasticity ◽

Temporal Variation ◽

Temporal Stability ◽

Common Garden ◽

Grassland Management ◽

Land Use Intensity ◽

Evolutionary Changes ◽

Biomass Removal ◽

Reproductive Biomass

Abstract Aims Plant populations in managed grasslands are subject to strong selection exerted by grazing, mowing and fertilization. Many previous studies showed that this can cause evolutionary changes in mean trait values, but little is known about the evolution of phenotypic plasticity in response to land use. In this study, we aimed to elucidate the relationships between phenotypic plasticity – specifically, regrowth ability after biomass removal – and the intensity of grassland management and levels of temporal variation therein. Methods We conducted an outdoor common garden experiment to test if plants from more intensively mown and grazed sites showed an increased ability to regrow after biomass removal. We used three common plant species from temperate European grasslands, with seed material from 58 – 68 populations along gradients of land-use intensity, ranging from extensive (only light grazing) to very intensive management (up to four cuts per year). Important findings In two out of three species, we found significant population differentiation in regrowth ability after clipping. While variation in regrowth ability was unrelated to the mean land-use intensity of populations of origin, we found a relationship with its temporal variation in P. lanceolata, where plants experiencing less variable environmental conditions over the last 11 years showed stronger regrowth in reproductive biomass after clipping. Therefore, while mean grazing and mowing intensity may not select for regrowth ability, the temporal stability of the environmental heterogeneity created by land use may have caused its evolution in some species.

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Adaptation of Mediterranean forest species to climate: lessons from common garden experiments

Journal of Ecology ◽

10.1111/1365-2745.13730 ◽

2021 ◽

Author(s):

JA Ramírez‐Valiente ◽

L Santos del Blanco ◽

R Alía ◽

JJ Robledo‐Arnuncio ◽

J Climent

Keyword(s):

Common Garden ◽

Mediterranean Forest ◽

Forest Species ◽

Common Garden Experiments

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The role of waterlogging and sand accretion in modulating the morphology of the dune slack plant Scirpus americanus

Canadian Journal of Botany ◽

10.1139/b90-230 ◽

1990 ◽

Vol 68 (8) ◽

pp. 1780-1787 ◽

Cited By ~ 12

Author(s):

Denise M. Seliskar

Keyword(s):

Sand Dune ◽

Plant Morphology ◽

Common Garden ◽

Stem Growth ◽

Reciprocal Transplant ◽

Dune Slack ◽

Coastal Sand Dune ◽

Scirpus Americanus ◽

Common Garden Experiments

Scirpus americanus Pers., a major dune slack plant in coastal sand dune ecosystems, differs in height along transects ranging between the lowest and highest elevational areas of slacks located along the coast of Delaware, U.S.A. Using reciprocal transplant and common garden experiments, results suggest that environmental factors rather than hereditary traits are more important in accounting for the differences in plant morphology expressed in the field. Dune slack plants are exposed to stresses of waterlogging and sand accretion in their natural environment. In controlled greenhouse experiments waterlogging was shown to inhibit stem growth and cause an increase in aerenchymatous tissue, whereas periodic sand deposition caused an increase in the plant height of Scirpus.

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