Biology subjects

Chaparro-Pedraza, C.

Publications and source records attributed to Chaparro-Pedraza, C..

3 recordsLinked to original sources

bioRxiv2025

Life history evolution facilitates trophic diversification

To what extent is biodiversity shaped by environmental conditions, and to what extent is it the result of self-organization? Both natural processes and structural features may contribute to promoting diversity. Here, we show that one such process, namely natural selection, and a structural feature, namely organismal life history, interact in a feedback mechanism that promotes the emergence of diversity. We illustrate how this mechanism operates using various models of ecological diversification driven by intraspecific resource competition, in which both a niche trait that determines resource use and a life history trait can evolve. We find that natural selection that acts on life history traits leads to increased competition, which, in the presence of ecological opportunity, facilitates niche diversification. As a consequence, the environmental conditions (e.g. productivity) for diversification are more restrictive in the absence of life history evolution than in its presence. Our findings indicate a strong influence of life history evolution on ecological processes that in turn shape the origin of biodiversity. Our results call for a better integration of life history evolution and ecological diversification in theoretical and empirical research.

evolutionary biology↗

bioRxiv2024

Ecological diversification in sexual and asexual lineages

The presence or absence of sex can have a strong influence on the processes whereby species arise. Yet, the mechanistic underpinnings of this influence are poorly understood. To gain insights into the mechanisms whereby the reproductive mode may influence diversification, we investigate how natural selection, genetic mixing and the reproductive mode interact and how this interaction affects the evolutionary dynamics of diversifying lineages. To do so, we formulate and analyze trait-based eco-evolutionary models of ecological diversification for sexual and asexual lineages, in which diversification is driven by intraspecific resource competition. We find that the reproductive mode strongly influences the diversification rate and thus the ensuing diversity of a lineage. Our results reveal that natural selection is stronger in asexual lineages because asexual organisms have a higher reproductive potential than sexual ones. As a consequence, an asexual population can reach a higher population density than a sexual population under the very same ecological conditions. This causes competition, and thus ecologically-based selection, to be stronger in asexual lineages, promoting faster diversification. However, a small amount of genetic mixing accelerates the trait expansion process in sexual lineages, overturning the effect of selection alone and enabling a faster niche occupancy than asexual lineages. As a consequence, sexual lineages can occupy more ecological niches, eventually resulting in higher diversity. This suggests that sexual reproduction may be widespread among species because it increases rates of diversification.

evolutionary biology↗

bioRxiv2022

Differential stage-specific mortality as a mechanism for diversification

Individual variability in mortality is widespread in nature. The general rule is that larger organisms have a greater chance of survival than smaller conspecifics. There is growing evidence that differential mortality between developmental stages has important consequences for the ecology and evolution of populations and communities. However, we know little about how it can influence diversification. Using an eco-evolutionary model of diversification that considers individual variability in mortality, we show that commonly observed differences in mortality between juveniles and adults facilitate ecological diversification. We find that juvenile-biased mortality reduces the threshold of minimum resource productivity required for diversification. Diversification is hence less restricted when mortality is more biased towards juveniles than when all individuals experience the same mortality rate. This is because, by altering the population composition, juvenile-biased mortality increases the strength of intraspecific competition. Strong intraspecific competition in turn induces frequency-dependent selection, which drives ecological diversification. Our results demonstrate the strong influence that differential mortality between developmental stages has on diversification, and highlight the need for integrating developmental processes into the theoretical framework of diversification.

evolutionary biology↗