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Tomás Ignacio González

Publications and source records attributed to Tomás Ignacio González.

3 recordsLinked to original sources

Energy, space and competition: A model of territorial organization in camelids

Ecological theory predicts that herbivores adopt behaviors that balance energetic costs and benefits, shaping both foraging and reproductive organization. In some wild ungulates, such as camelids, males defend resource-rich areas to attract females and secure their offspring, leading to the emergence of territorial systems. However, existing territorial models rarely incorporate the well-established allometric relationships between body mass and metabolic costs. In this study, we develop a spatially explicit, individual-based model of territorial organization in camelids, in which male behavior is governed by an energy balance equation that includes allometric locomotion costs, resource acquisition, and the energetic risks of aggressive encounters. We show that (i) a body-mass-dependent threshold determines which individuals can establish and maintain territories, (ii) spatial resource connectivity strongly modulates competition intensity and territorial inequality, and (iii) confrontation costs play a key stabilizing role by limiting territorial expansion and promoting coexistence. Our results provide a mechanistic link between metabolic scaling, spatial structure, and social organization, offering new insights into the ecological and evolutionary drivers of territoriality in ungulates.

q-bio.PE↗

From female choice to social structure: Modeling harem formation in camelids

Herbivorous wild species constantly strive to optimize the trade-off between energy and nutrient intake and predation risk during foraging. This has led to the selection of several evolutionary traits -- such as diet, habitat selection, and behavior -- which are simultaneously shaped by the spatio-temporal variability of the habitat. Among camelid species, polygyny is a prevalent behavioral strategy that encompasses both mating and foraging activities. This group-level behavior has multiple interacting dimensions, contributing to an interesting ecological and evolutionary complexity. We developed an individual-based stochastic model in which camelid females transition between different familial groups in response to their environmental conditions, aiming to maximize individual fitness. Our results indicate that the behavioral strategy of individual females can shape, by itself, emergent population-level properties, including group size and fitness distribution. Furthermore, these properties are modulated, in a non-additive manner, by other factors such as population density, sex ratio and system heterogeneity.

q-bio.PE↗

A mean field analysis of the role of indirect transmission in emergent infection events

We developed a mathematical model to investigate the role of indirect transmission in the spread of infectious diseases, using the illustrative example of sarcoptic mange as a case study. This disease can be transmitted through direct contact between an infected host and a susceptible one, or indirectly when potential hosts encounter infectious mites and larvae deposited in the environment, commonly referred to as fomites. Our focus is on exploring the potential of these infectious reservoirs as triggers for emerging infection events and as stable reservoirs of the disease. To achieve this, our mean field compartmental model incorporates the epidemiological dynamics driven by indirect transmission via fomites. We identify different types of dynamics that the system can go into, controlled by different levels of direct and indirect transmission. Among these, we find a new regime where the disease can emerge and persist over time solely through fomites, without the necessity for direct transmission. This possibility of the system reveals an evolutionary pathway that could enable the parasite to enhance its fitness beyond host co-evolution. We also define a new threshold based on an effective reproductive number, that enables us to predict the conditions for disease persistence. Our model allows us to assess the potential effectiveness of various disease intervention measures by incorporating a feature observed in real systems. We hope this contributes to a better understanding of infectious disease outbreaks.

q-bio.PE↗