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Understanding the processes regulating population temporal stability is important to infer species coexistence and ecosystem stability patterns. It has been hypothesized that population temporal stability could be driven by functional trade-offs in resource acquisition and growth rate strategies. We tested this hypothesis by analyzing a 13-year data set from a mown grassland community in a factorial experiment with fertilization and dominant removal as the main treatment effects. Population temporal stability, measured as a coefficient of variation of species' biomass over time, was related to plant traits covering different functional trade-offs. These included plant height, leaf dry matter content (LDMC), specific leaf area, seed mass, leaf δ 13 C, and rooting depth. Three of the traits (LDMC, rooting depth, and leaf δ 13 C) had significant relationships with population temporal stability, even after accounting for species' phylogenetic relatedness. Higher values of LDMC, the best predictor, were consistently associated with greater population temporal stability across all experimental conditions. This suggests a functional trade-off along the leaf economics spectrum, with more conservative, slow-growing species being more stable over time. Incorporating functional trade-offs into the assessment of population temporal dynamics will allow for a more comprehensive understanding of the processes that sustain the stability of ecosystems and species coexistence.

Background Sexual selection theory is a multifaceted area of evolutionary research that has profound implications across various disciplines, including population genetics, evolutionary ecology, animal behavior, sociology, and psychology. It explores the mechanisms by which certain traits and behaviors evolve due to mate choice and competition within a species. In the context of this theory, the Jeffreys divergence measure, also known as population stability index, plays a key role in quantifying the information obtained when a deviation from random mating occurs for both discrete and continuous data. Despite the critical importance of understanding mating patterns in the context of sexual selection, there is currently no software available that can perform model selection and multimodel inference with quantitative mating data to test hypotheses about the dynamics underlying observed mating patterns. Recognizing this gap, I have developed QInfoMating which provides a comprehensive solution for analyzing and interpreting mating data within the framework of sexual selection theory. Results The program QInfoMating incorporates a user-friendly interface for performing statistical tests, best-fit model selection, and parameter estimation using multimodel inference for both discrete and continuous mating data. A use case is presented with real data of the species Echinolittorina malaccana . Conclusions The application of information theory, model selection, and parameter estimation using multimodel inference are presented as powerful tools for the analysis of mating data, whether quantitative or categorical. The QInfoMating program is a tool designed to perform this type of analysis.

Numerous studies have demonstrated that biodiversity drives ecosystem functioning, yet how biodiversity loss alters ecosystems functioning and stability in the long-term lacks experimental evidence. We report temporal effects of species richness on community productivity, stability, species asynchrony, and complementarity, and how the relationships among them change over 17 years in a grassland biodiversity experiment. Productivity declined more rapidly in less diverse communities resulting in temporally strengthening positive effects of richness on productivity, complementarity, and stability. In later years asynchrony played a more important role in increasing community stability as the negative effect of richness on population stability diminished. Only during later years did species complementarity relate to species asynchrony. These results show that species complementarity and asynchrony can take more than a decade to develop strong stabilizing effects on ecosystem functioning in diverse plant communities. Thus, the mechanisms stabilizing ecosystem functioning change with community age. Biodiversity-ecosystem functioning relationships may change over time. Here, Wagg et al. show that richness-productivity and richness stability relationships grow stronger over time in an experimental grassland community, and shed light on the ecological mechanisms.

The rate of evolution of population mean fitness informs how selection acting in contemporary populations can counteract environmental change and genetic degradation (mutation, gene flow, drift, recombination). This rate influences population increases (e.g., range expansion), population stability (e.g., cryptic eco-evolutionary dynamics), and population recovery (i.e., evolutionary rescue). We review approaches for estimating such rates, especially in wild populations. We then review empirical estimates derived from two approaches: mutation accumulation (MA) and additive genetic variance in fitness (I Aw ). MA studies inform how selection counters genetic degradation arising from deleterious mutations, typically generating estimates of <1% per generation. I Aw studies provide an integrated prediction of proportional change per generation, nearly always generating estimates of <20% and, more typically, <10%. Overall, considerable, but not unlimited, evolutionary potential exists in populations facing detrimental environmental or genetic change. However, further studies with diverse methods and species are required for more robust and general insights.

1. Global environmental changes are altering ecosystem stability, sometimes by altering biodiversity. For example, by driving grassland plant species loss, nitrogen (N) addition can reduce ecosystem stability. In other cases, however, N addition may alter productivity and ecosystem stability, by increasing the dominance of particularly productive or stable species. 2. We examined how N addition affected plant diversity, productivity and the temporal stability of productivity in an 8-year grassland experiment. We found that N addition enhanced productivity and decreased ecosystem stability throughout the experimental period, even though it reduced species richness in the first 4 years, but increased richness during the subsequent years. 3. During the early years, N addition decreased ecosystem stability by synchronizing species fluctuations and population stability of the dominant species. During later years, N addition did not increase stability, even though it increased species richness; instead, N addition continued to decrease ecosystem stability by decreasing species dominance and stability of the dominant species, without changing the identity of the dominant species. 4. Synthesis. Our results indicate that N addition decreased ecosystem stability via mechanisms that were both dependent and independent of plant diversity, and that the mechanisms involved shifted over time. N addition impacted on ecosystem functioning through species richness and the effects on species dominance and the stability of most dominant species, highlighting the join effect of multiple biotic drivers in regulating ecosystem stability.

Climate-mediated changes in thermal stress can destabilize animal populations and promote extinction risk. However, risk assessments often focus on changes in mean temperatures and thus ignore the role of temporal variability or structure. Using Earth System Model projections, we show that significant regional differences in the statistical distribution of temperature will emerge over time and give rise to shifts in the mean, variability and persistence of thermal stress. Integrating these trends into mathematical models that simulate the dynamical and cumulative effects of thermal stress on the performance of 38 globally distributed ectotherm species revealed complex regional changes in population stability over the twenty-first century, with temperate species facing higher risk. Yet despite their idiosyncratic effects on stability, projected temperatures universally increased extinction risk. Overall, these results show that the effects of climate change may be more extensive than previously predicted on the basis of the statistical relationship between biological performance and average temperature.The authors project changes in mean thermal stress, as well as its persistence and variability. They show complex impacts on species stability but universal increases in extinction risk, and highlight the need to go beyond average-temperature-based projections of biological performance.

Genetic and paleoanthropological evidence is in accord that today’s human population is the result of a great demic (demographic and geographic) expansion that began approximately 45,000 to 60,000 y ago in Africa and rapidly resulted in human occupation of almost all of the Earth’s habitable regions. Genomic data from contemporary humans suggest that this expansion was accompanied by a continuous loss of genetic diversity, a result of what is called the “serial founder effect.” In addition to genomic data, the serial founder effect model is now supported by the genetics of human parasites, morphology, and linguistics. This particular population history gave rise to the two defining features of genetic variation in humans: genomes from the substructured populations of Africa retain an exceptional number of unique variants, and there is a dramatic reduction in genetic diversity within populations living outside of Africa. These two patterns are relevant for medical genetic studies mapping genotypes to phenotypes and for inferring the power of natural selection in human history. It should be appreciated that the initial expansion and subsequent serial founder effect were determined by demographic and sociocultural factors associated with hunter-gatherer populations. How do we reconcile this major demic expansion with the population stability that followed for thousands years until the inventions of agriculture? We review advances in understanding the genetic diversity within Africa and the great human expansion out of Africa and offer hypotheses that can help to establish a more synthetic view of modern human evolution.

Life‐history strategies can buffer individuals and populations from environmental variability. For instance, it is possible that asynchronous dynamics among different life histories can stabilize populations through portfolio effects. Here, we examine life‐history diversity and its importance to stability for an iconic migratory fish species. In particular, we examined steelhead (Oncorhynchus mykiss), an anadromous and iteroparous salmonid, in two large, relatively pristine, watersheds, the Skeena and Nass, in north‐western British Columbia, Canada. We synthesized life‐history information derived from scales collected from adult steelhead (N = 7227) in these watersheds across a decade. These migratory fishes expressed 36 different manifestations of the anadromous life‐history strategy, with 16 different combinations of freshwater and marine ages, 7·6% of fish performing multiple spawning migrations, and up to a maximum of four spawning migrations per lifetime. Furthermore, in the Nass watershed, various life histories were differently prevalent through time – three different life histories were the most prevalent in a given year, and no life history ever represented more than 45% of the population. These asynchronous dynamics among life histories decreased the variability of numerical abundance and biomass of the aggregated population so that it was > 20% more stable than the stability of the weighted average of specific life histories: evidence of a substantial portfolio effect. Year of ocean entry was a key driver of dynamics; the median correlation coefficient of abundance of life histories that entered the ocean the same year was 2·5 times higher than the median pairwise coefficient of life histories that entered the ocean at different times. Simulations illustrated how different elements of life‐history diversity contribute to stability and persistence of populations. This study provides evidence that life‐history diversity can dampen fluctuations in population abundances and biomass via portfolio effects. Conserving genetic integrity and habitat diversity in these and other large watersheds can enable a diversity of life histories that increases population and biomass stability in the face of environmental variability.

The potential for climate change and temperature shifts to affect community stability remains relatively unknown. One mechanism by which temperature may affect stability is by altering trophic interactions. The functional response quantifies the per capita resource consumption by the consumer as a function of resource abundance and is a suitable framework for the description of nonlinear trophic interactions. We studied the effect of temperature on a ciliate predator–prey pair (Spathidium sp. and Dexiostoma campylum) by estimating warming effects on the functional response and on the associated conversion efficiency of the predator. We recorded prey and predator dynamics over 24 hr and at three temperature levels (15, 20 and 25°C). To these data, we fitted a population dynamic model including the predator functional response, such that the functional response parameters (space clearance rate, handling time and density dependence of space clearance rate) were estimated for each temperature separately. To evaluate the ecological significance of temperature effects on the functional response parameters, we simulated predator–prey population dynamics. We considered the predator–prey system to be destabilized, if the prey was driven extinct by the predator. Effects of increased temperature included a transition of the functional response from a Type III to a Type II and an increase of the conversion efficiency of the predator. The simulated population dynamics showed a destabilization of the system with warming, with greater risk of prey extinction at higher temperatures likely caused by the transition from a Type III to a Type II functional response. Warming‐induced shifts from a Type III to II are not commonly considered in modelling studies that investigate how population dynamics respond to warming. Future studies should investigate the mechanism and generality of the effect we observed and simulate temperature effects in complex food webs including shifts in the type of the functional response as well as consider the possibility of a temperature‐dependent conversion efficiency. The authors study highlights that warming can induce shifts in the functional response type of a predator–prey system by lowering the scaling exponent q. In contrast, modelling studies exploring the consequences of warming often rely on a single fixed functional response type and hence overlook a potential destabilization of a system due to changes in the functional response type.

Despite growing concern over consequences of global changes, we still know little about potential interactive effects of anthropogenic perturbations and diversity loss on the stability of local communities, especially for taxa other than plants. Here we analyse the relationships among landscape composition, biodiversity and community stability looking at time series of three types of communities, i.e., bats, birds and butterflies, monitored over the years by citizen science programs in France. We show that urban and intensive agricultural landscapes as well as diversity loss destabilize these communities but in different ways: while diversity loss translates into greater population synchrony, urban and intensive agricultural landscapes mainly decrease mean population stability. In addition to highlight the stabilizing effects of diversity on ecologically important but overlooked taxa, our results further reveal new pathways linking anthropogenic activities to diversity and stability.