Life history evolution under climate change and its influence on the population dynamics of a long‐lived plant

Abstract

Summary 1.One of the key components of an organism's life history is the delay of reproduction until it reaches or returns to an optimal size. While we know climate can influence vital rates that shape life-history strategies, it is also critical to understand the effects of climate change on rapid life history evolution, which might modify the influence of climate change on population dynamics. 2. We asked how realistic changes in temperature and precipitation influence vital rates, costs of reproduction, and ultimately, evolutionarily stable (ES) flowering size in a long-lived perennial plant, Orchis purpurea. We also explored how evolution of flowering size could influence population persistence under changing climate. 3. Our approach combined model selection methods to characterize climate dependence in vital rates, stochastic integral projection models to integrate vital rates into an estimate of fitness, and adaptive dynamics to identify ES flowering sizes. 4. Vital rates responded uniquely to seasonal temperature and precipitation, with the largest response in the size-dependent probability of flowering. The predicted ES flowering size closely matched that observed, and responded strongly to adjusting the frequencies of extreme climate years. For example, increasing the frequency of extreme drought conditions was predicted to favour smaller reproductive sizes (and hence a shorter reproductive delay), despite observation that smaller plants were less likely to flower in dry years. This apparent discrepancy stems from a smaller payoff to delaying reproduction due to lower costs of reproduction in dry years. 5. The model of stochastic population dynamics predicted long-term persistence of the focal populations, even under the most extreme climate scenarios, while incorporating rapid life history evolution into predictions reduced the sensitivity of population growth to changing climate. 6. Synthesis. Our results illustrate that long-lived organisms can exhibit complex demographic responses to changing climate regimes. Additionally, they highlight that long-term evolutionary responses may be in opposing directions from short-term plastic responses to climate and emphasize the need for demographic models to integrate ecological and evolutionary influences of climate across the life cycle.

Low interannual precipitation has a greater negative effect than seedling herbivory on the population dynamics of a short‐lived shrub, Schiedea obovata

“…Increased precipitation also had a positive influence on S. obovata seedling establishment. The influence of precipitation on the probability of fruiting and reproductive output was also consistent with results from previous studies (Kadmon, ; Williams et al., ). For earlier life stages (i.e., seedling and small vegetative plants), however, increased wet season precipitation reduced subsequent survival.…”

The effect of demographic correlations on the stochastic population dynamics of perennial plants

“…Positive correlation of vital rates through time (e.g., years that are bad for reproduction are also bad for survival) is expected to increase the variability in population growth, making the effect of temporal variance on the long-term stochastic growth rate (λ s ) more negative than if vital rates varied independently. For example, costs of reproduction in plants could make years that are favorable for flowering unfavorable for growth, and vice versa (Williams et al 2015). On the other hand, negative correlation through time (e.g., years that are good for reproduction are bad for survival, and vice versa) is expected to decrease the variability of population growth, thereby buffering the negative effect of temporal variance on the long-term stochastic growth rate.…”

Predicting population viability of the narrow endemic Mediterranean plant Centaurea corymbosa under climate change

“…Compared to some other taxonomic groups, plants are more 29 vulnerable to climate change since they have relatively low migration capacity (Malcolm et al, 30 2006;Thomas et al, 2004). Gradual climate change and extreme events have already caused range 31 shifts for some plant species (Chen et al, 2011), including range contraction with long-term 32 population declines and extinctions (Lennartsson and Oostermeijer, 2001;Doak and Morris, 2010;33 Selwood et al, 2015, Wiens, 2016, or range expansion (Meer et al, 2016;Williams et al, 2015).…”

“…For instance, climate change proved beneficial to 44 populations of the widespread orchid species (Orchis purpurea) and is predicted to induce range 45 expansion in the near future (Meer et al, 2016;Williams et al, 2015). In contrast, several studies 46 have documented negative effects of summer temperature on growth rates for other plant species (Aragón-Gastélum et al, 2017;Riba et al, 2002;Shryock et al, 2014).…”

“…Based on the results of the GLM analyses 294 testing for the effects of climatic variables on asymptotic growth rates, we used the daily mean 295 temperature and the number of wet days to characterize warm and dry scenarios, respectively. Following Williams et al (2015), extreme years corresponded to years with climate values larger 297 than one standard deviation above the daily mean for temperature and lower than one standard 298 deviation below the mean for precipitation. In the warm scenario, warm years were represented by 299 pair-of-years with high daily mean temperature (2006-2007, 2013-2014, 2014-2015 and 2015-2016, 300 Fig.…”