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Colombo, E. H.

Publications and source records attributed to Colombo, E. H..

2 recordsLinked to original sources

Connecting metapopulation heterogeneity to aggregated lifetime statistics

Aggregated metapopulation lifetime statistics has been used to access stylized facts that might help identify the underlying patch-level dynamics. For instance, the emergence of scaling laws in the aggregated probability distribution of patch lifetimes can be associated to critical phenomena, in which the correlation length among system units tends to diverge. Nevertheless, an aggregated approach is biased by patch-level variability, a fact that can blur the interpretation of the data. Here, I propose a weakly-coupled metapopulation model to show how patch variability can solely trigger qualitatively different lifetime probability distribution at the aggregated level. In a generalized approach, I obtain a two-way connection between the variability of a certain patch property (e.g. carrying capacity, environment condition or connectivity) and the aggregated lifetime probability distribution. Furthermore, for a particular case, assuming that scaling laws are observed at the aggregated-level, I speculate the heterogeneity that could be behind it, relating the qualitative features the variability (mean, variance and concentration) to the scaling exponents. In this perspective, the application points to the possibility of equivalence between heterogeneous weakly-coupled metapopulations and homogeneous ones that exhibit critical behavior.

ecology

Spatial eco-evolutionary feedbacks mediate coexistence inprey-predator systems

Eco-evolutionary frameworks can explain certain features of communities in which ecological and evolutionary processes occur over comparable timescales. In the particular case of prey-predator systems, a combination of empirical and theoretical studies have explored this possibility, showing that the evolution of prey traits, predator traits or the coevolution of both can contribute to the stability of the community, as well as to the emergence of various types of population cycles. However, these studies overlook that interactions are spatially constrained, a crucial ingredient known to foster species coexistence per se. Here, we investigate whether evolutionary dynamics interacts with the spatial structure of a prey-predator community in which both species show limited mobility and predators perceptual ranges are subject to natural selection. In these conditions, our results unveil an eco-evolutionary feedback between species spatial mixing and predators perceptual range: different levels of species mixing select for different perceptual ranges, which in turn reshape the spatial distribution of preys and their interaction with predators. This emergent pattern of interspecific interactions feeds back to the efficiency of the various perceptual ranges, thus selecting for new ones. Finally, since prey-predator mixing is the key factor that regulates the intensity of predation, we explore the community-level implications of such feedback and show that it controls both coexistence times and species extinction probabilities. Author summaryEvolutionary processes occurring on temporal scales that are comparable to those of ecological change can result in reciprocal interactions between ecology and evolution termed eco-evolutionary feedbacks. Such interplay is clear in prey-predator systems, in which predation alters the distribution of resources (preys). In turn, changes in the abundance and spatial distribution of preys may lead to the evolution of new predation strategies, which may change again the properties of the prey population. Here, we investigate the interplay between limited mobility, species mixing, and finite perception in a prey-predator system. We focus on the case in which predator perceptual ranges are subject to natural selection and examine, via coexistence times and species extinction probabilities, whether the resulting eco-evolutionary dynamics mediates the stability of the community. Our results confirm the existence of such eco-evolutionary feedback and reveal its potential impact on community-level processes.

ecology