Find research datasets worth reusing

opencc-zeroMar 2024View details →

Data from: Trait-fitness associations via fecundity and competition in a two-million-year-long fossil record

The evolution of phenotypic traits is usually studied on generational times or across species on million-year timescales. We bridge this conceptual gap by using high density sampling of a species lineage, Microporella agonistes (Bryozoa, Cheilostomatida), over 2 million years of its evolutionary history, to ask if trait-fitness associations are consistent with evolutionary trait models often applied to phenotypic time series. We use average fecundity and competitive outcome as two different fitness components, where competitive outcome is a proxy for partial survival. Examining three quantitative traits in multivariate analyses, we present evidence that some traits experienced substantial selective pressures, in part controlled by past environments. A complex interplay of resource competition with an altering set of competitors and past temperatures, has contributed to the changing patterns of phenotypes within the focal species. A comparison with congeneric species living in the same regional community suggests that size traits are more temporally variable and less constrained than shape traits. Our analyses also show that while controls on phenotypes are complex and varied in time, ecological and evolutionary processes that unfold on shorter time scales are not inconsistent with macroevolutionary patterns observed on longer timescales.

opencc-zeroAug 2023View details →

Data and reproducible code for Honor et al: Direct and indirect fitness effects of competition limit evolution of allelopathy in an invading plant

Upon introduction to new continents, invading species encounter novel communities of consumers, pathogens, and competitors. Both phenotypic plasticity and rapid evolution can facilitate adaptation across these heterogenous communities, facilitating further invasion. However, the rate and extent of adaptive evolution on contemporary timescales can be constrained by phenotypic plasticity and limits imposed by genetic co-variation for traits under selection. We measured phenotypic plasticity and quantified genetic co-variation for growth, competition, and fitness among 23 naturally inbred seed families of Alliaria petiolata (garlic mustard) collected across its invasive range in eastern North America. After growing a self-pollinated generation in a uniform common garden to reduce maternal effects, we reared second-generation plants in a two-year greenhouse and field experiment with naïve soil from an uninvaded habitat. We measured selection gradients and lifetime fitness when reared alone, with an intraspecific competitor, and under interspecific competition with naïve Acer saccharum (sugar maple) saplings. Total glucosinolate production was strongly correlated with the production of chlorophyll a (Chl a) (R2 = 0.45) such that first principal component (PC1) accounted for 84% of variation in these two traits. Furthermore, PC1 exhibited high plasticity across growing environments (p < 0.001) with limited broad-sense heritability (H2 = 2.91; p = 0.08). In contrast, investment in glucosinolate production relative to Chl a (PC2) was significantly heritable (H2 =16.91, p < 0.001) with minimal plasticity across treatments. Causal analysis revealed that plastic variation for higher Chl a + glucosinolate production (PC1) had an indirect positive effect on A. petiolata fitness via a direct, negative effect on A. saccharum performance. In contrast, heritable variation for higher glucosinolate investment (PC2) had a direct, positive effect on A. saccharum performance and an indirect negative effect on A. petiolata fitness. Applying causal inference, we find that evolution of allelopathy in A. petiolata has been constrained by (i) a lack of genetic variation, (ii) selection against glucosinolate investment under interspecific competition, and (iii) phenotypic plasticity. These factors limit adaptive evolution but maintain fitness during population growth as plants switch from interspecific to intraspecific competition during invasion.

opencc-zeroSep 2023View details →

Alien plant fitness is limited by functional trade-offs rather than a long-term increase in competitive effects of native communities

Alien plants experience novel abiotic conditions and interactions with native communities in the introduced area. Intra- and interspecific selection on functional traits in the new environment may lead to increased population growth with time since introduction (residence time). However, selection regimes might differ depending on the invaded habitat. Additionally, in high-competition habitats, a build-up of biotic resistance of native species due to accumulation of eco-evolutionary experience to aliens over time may limit invasion success. We tested if the effect of functional traits and the population dynamics of aliens depends on interspecific competition with native plant communities. We conducted a multi-species experiment with 40 annual Asteraceae that differ in residence time in Germany. We followed their population growth in monocultures and in interspecific competition with an experienced native community (varying co-existence times between focals and community). To more robustly test our findings, we used a naïve community that never co-existed with the focals. We found that high seed mass decreased population growth in monocultures but tended to increase population growth under high interspecific competition. We found no evidence for a build-up of competition-mediated biotic resistance by the experienced community over time. Instead, population growth of the focal species was similarly inhibited by the experienced and naïve community. By comparing the effect of experienced and naïve communities on population dynamics over two years across a large set of species with a high variation in functional traits and residence time, this study advances the understanding of the long-term dynamics of plant invasions. In our study system, population growth of alien species was not limited by an increase of competitive effects by native communities (one aspect of biotic resistance) over time. Instead, invasion success of alien plants may be limited because initial spread in low-competition habitats requires different traits than establishment in high-competition habitats.

zenodo40/100

Non-additive interaction between genotypes: implications for competitive fitness assays

Competitive fitness assays are widely used in evolutionary biology and typically rely on a reference strain to compare different focal genotypes. This approach implicitly relies on the absence of interaction between the competing genotypes. In other words, the performance of the reference strain must not depend on the competitor. This report scrutinized this assumption by competing diverged Drosophila simulans populations against a common reference strain. We detected strong evidence for interaction between the competing genotypes: 1) Frequency-dependent selection was common with opposite effects in genetically diverged populations. 2) Temporal heterogeneity of fitness estimates, which can be partially attributed to a competitor-specific delay in the eclosion of the reference strain. We propose that this inconsistent behavior of the reference strain can be considered a specific case of a genotype x environment interaction. Focal populations could modify the environment of the reference strain, either indirectly by altering the microbiome composition and food availability or directly by genotype-specific cannibalism. Our results provide new insights into the interaction of diverged genotypes and have important implications for the interpretation of competitive fitness assays.

opencc-by-4.0Jul 2023View details →

publicMay 2024View details →

Data from: Trait-fitness associations via fecundity and competition in a two-million-year-long fossil record

Open the record for dataset details and reuse information.

publicSep 2023View details →

Alien plant fitness is limited by functional trade-offs rather than a long-term increase in competitive effects of native communities

Open the record for dataset details and reuse information.

publicAug 2023View details →

Data and reproducible code for Honor et al: Direct and indirect fitness effects of competition limit evolution of allelopathy in an invading plant

Open the record for dataset details and reuse information.

zenodo36/100

Data and code for "Competition contributes to quantitative mismatches between plant fitness and occurrence along environmental gradients"

This repository contains data and code for the following manuscript: Hayashi, K. T., & Kraft, N. J. B. (2025). Competition contributes to quantitative mismatches between plant fitness and occurrence along environmental gradients. Journal of Ecology, 113, 2590–2602. <a href="https://doi.org/10.1111/1365-2745.70115">https://doi.org/10.1111/1365-2745.70115</a>

opencc-zeroNov 2024View details →

opencc-zeroJul 2021View details →

Data from: The effects of competition on fitness depend on the sex of both competitors

In intraspecific competition, the sex of competing individuals is likely to be important in determining the consequences of competition, both for the immediate outcome of competitive interactions, and for long-term effects of competition during development on adult fitness traits. Previous studies have explored differences between males and females in their response to intraspecific competition. However, few have tested how the sex of the competitors, or any interactions between focal and competitor sex, influence the nature and intensity of competition. We set up larval seed beetles Callosobruchus maculatus to develop either alone or in the presence of a male or female competitor, and measured a suite of traits: development time, emergence weight; male ejaculate mass, copulation duration and lifespan; and female lifetime fecundity, offspring egg-adult survival and lifespan. We found effects of competition and competitor sex on the development time and emergence weight of both males and females, and also of an interaction between focal and competitor sex: females but not males responded differently to competitor sex. There was little effect of larval competition on male and female adult fitness traits, with the exception of the effect of a female competitor on a focal female's offspring survival rate. Our results highlight the importance of directly measuring the effects of competition on fitness traits, rather than distant proxies for fitness, and suggest that competition with the sex with the greater resource requirements (here females) might have a strong effect in driving trait evolution. We also found that male-male competition during development resulted in shorter copulation times than male-female competition, a result that remained when controlling for the weight of competitors. Although it is difficult to definitively tease apart the effects of social environment and access to resources, this result suggests that something about the sex of competitors other than their size is driving this pattern.

opencc-zeroDec 2022View details →

Data for: Fitness costs of female competition linked to resource defence and relatedness of competitors

Female reproductive success is often limited by access to resources and this can lead to social competition both within and between kin groups. Theory predicts that both resource availability and relatedness should influence the fitness consequences of social competition. However, testing key predictions requires differentiating the effects of these two factors. Here we achieve this experimentally by manipulating the social environment of house mice, a facultative communal breeding species with known kin discrimination ability. Our results support the hypothesis that resource defence can be costly for females, potentially trading off against maternal investment. When competition for nest sites was more intense, subjects: 1) were more active during resting phases, 2) responded more strongly to simulated territory intrusions via competitive signalling, and 3) produced smaller weaned offspring. However, we found no evidence that the propensity for kin to cooperate was influenced by relatedness of rivals. Communal breeding between sisters occurred independently of the relatedness of competitors, and costs of competition with non-kin were not mitigated by greater inclusive fitness benefits. Rather, communally breeding sisters weaned fewer offspring when competing with unrelated females, indicating that competition with non-kin is more costly overall. Our findings thus demonstrate that social competition has fitness costs and that associating with kin is beneficial to avoid negative fitness consequences of competing with non-kin, in addition to more widely recognised kin-selected benefits.

publicJul 2021View details →

Data from: The effects of competition on fitness depend on the sex of both competitors

Open the record for dataset details and reuse information.

publicDec 2022View details →

Data for: Fitness costs of female competition linked to resource defence and relatedness of competitors

Open the record for dataset details and reuse information.

publicNov 2024View details →

Data from: Herbivory can increase plant fitness via reduced interspecific competition – evidence from models and mesocosms

Open the record for dataset details and reuse information.

opencc-zeroDec 2015View details →

Data from: Revising traditional theory on the link between plant body size and fitness under competition: evidence from old-field vegetation

The selection consequences of competition in plants have been traditionally interpreted based on a "size-advantage" hypothesis – that is, under intense crowding/competition from neighbors, natural selection generally favors capacity for a relatively large plant body size. However, this conflicts with abundant data, showing that resident species body size distributions are usually strongly right-skewed at virtually all scales within vegetation. Using surveys within sample plots and a neighbor-removal experiment, we tested: (1) whether resident species that have a larger maximum potential body size (MAX) generally have more successful local individual recruitment, and thus greater local abundance/density (as predicted by the traditional size-advantage hypothesis); and (2) whether there is a general between-species trade-off relationship between MAX and capacity to produce offspring when body size is severely suppressed by crowding/competition – that is, whether resident species with a larger MAX generally also need to reach a larger minimum reproductive threshold size (MIN) before they can reproduce at all. The results showed that MIN had a positive relationship with MAX across resident species, and local density – as well as local density of just reproductive individuals – was generally greater for species with smaller MIN (and hence smaller MAX). In addition, the cleared neighborhoods of larger target species (which had relatively large MIN) generally had – in the following growing season – a lower ratio of conspecific recruitment within these neighborhoods relative to recruitment of other (i.e., smaller) species (which had generally smaller MIN). These data are consistent with an alternative hypothesis based on a 'reproductive-economy-advantage' – that is, superior fitness under competition in plants generally requires not larger potential body size, but rather superior capacity to recruit offspring that are in turn capable of producing grand-offspring – and hence transmitting genes to future generations – despite intense and persistent (cross-generational) crowding/competition from near neighbors. Selection for the latter is expected to favor relatively small minimum reproductive threshold size and hence – as a tradeoff – relatively small (not large) potential body size.

opencc-zeroDec 2017View details →

Data from: Head-to-head comparison of three experimental methods of quantifying competitive fitness in C. elegans

Organismal fitness is relevant in many contexts in biology. The most meaningful experimental measure of fitness is competitive fitness, when two or more entities (e.g., genotypes) are allowed to compete directly. In theory, competitive fitness is simple to measure: an experimental population is initiated with the different types in known proportions and allowed to evolve under experimental conditions to a predefined endpoint. In practice, there are several obstacles to obtaining robust estimates of competitive fitness in multicellular organisms, the most pervasive of which is simply the time it takes to count many individuals of different types from many replicate populations. Methods by which counting can be automated in high throughput are desirable, but for automated methods to be useful, the bias and technical variance associated with the method must be (a) known, and (b) sufficiently small relative to other sources of bias and variance to make the effort worthwhile. The nematode Caenorhabditis elegans is an important model organism, and the fitness effects of genotype and environmental conditions are often of interest. We report a comparison of three experimental methods of quantifying competitive fitness, in which wild-type strains are competed against GFP-marked competitors under standard laboratory conditions. Population samples were split into three replicates and counted (1) "by eye" from a saved image, (2) from the same image using CellProfiler image analysis software, and (3) with a large particle flow cytometer (a "worm sorter"). From 720 replicate samples, neither the frequency of wild-type worms nor the among-sample variance differed significantly between the three methods. CellProfiler and the worm sorter provide at least a tenfold increase in sample handling speed with little (if any) bias or increase in variance.

ClinicalTrials.gov32/100

The Health of Competitive Fitness Athletes

ClinicalTrials.gov study NCT03007459. IPD Sharing: NO. Countries: 1. Publications: 1.

closedIPD-NOFeb 2026View details →

publicNov 2018View details →

Data from: Head-to-head comparison of three experimental methods of quantifying competitive fitness in C. elegans

Open the record for dataset details and reuse information.

publicSep 2015View details →

Data from: Fitness of crop-wild hybrid sunflowers under competitive conditions: implications for crop-to-wild introgression

Open the record for dataset details and reuse information.