biological systems
Thermodynamic origin of metabolic scaling
The origin and shape of metabolic scaling has been controversial since Kleiber found that basal metabolic rate of animals seemed to vary as a power law of their body mass with exponent 3/4, instead of 2/3, as a surface-to-volume argument predicts. The universality of exponent 3/4 -claimed in terms of the fractal properties of the nutrient network- has recently been challenged according to empirical evidence that observed a wealth of robust exponents deviating from 3/4. Here we present a conceptually simple thermodynamic framework, where the dependence of metabolic rate with body mass emerges from a trade-off between the energy dissipated as heat and the energy efficiently used by the organism to maintain its metabolism. This balance tunes the shape of an additive model from which different effective scalings can be recovered as particular cases, thereby reconciling previously inconsistent empirical evidence in mammals, birds, insects and even plants under a unified framework. This model is biologically motivated, fits remarkably well the data, and also explains additional features such as the relation between energy lost as heat and mass, the role and influence of different climatic environments or the difference found between endotherms and ectotherms.
Key papers
On the thermodynamic origin of metabolic scaling
Fernando Ballesteros, Vicent Martinez, Bartolo Luque, Lucas Lacasa, Enric Valor and Andres Moya
NPG Scientific Reports 8, 1448 (2018)
Featured in Investigación y Ciencia (spanish version of Scientific American) Science Daily
medicalxpress alphagalileo Institute for Integrative Systems Biology (University of Valencia) (English version) La Vanguardia (24/01/2018) Agencia Sinc (27/1/2018) Cátedra de Divulgación de la Ciencia (University of Valencia) Observatorio UPM (Technical University of Madrid) Comunica Valencia (27/1/2018) Tecnoxplora (lasexta | Atresmedia) El Espectador (4/2/2018) Radio Nacional de España (Broadcast min 19) La ciencia de la Mula Francis laoropendolasostenible datoanuncios.org CONEC
Animal foraging
The study of self-propelled particles is a fast-growing research topic where biologically inspired movement is increasingly becoming of much interest. A relevant example is the collective motion of social insects, whose variety and complexity offer fertile grounds for theoretical abstractions. It has been demonstrated that the collective motion involved in the searching behavior of termites is consistent with self-similarity, anomalous diffusion and Lévy walks. Our analysis indicates that the patterns observed for isolated termites change qualitatively when the termite density is increased, and such change cannot be explained by jamming effects only, pointing to collective effects emerging due to non-trivial foraging interactions between insects as the cause. Moreover, we find that such an onset of complexity is maximized for intermediate termite densities.
Key papers
Visibility graphs of animal foraging trajectories
Leticia R. Paiva, Sidiney G. Alves, Lucas Lacasa, Og DeSouza, Octavio Miramontes
Submitted
Ecology
Our group has current research collaborations with field ecologists (Anna Traveset lab). In this context, we explore ecological systems from a complex systems point of view, merging data analysis and mathematical modelling.
Key papers
Jordi Bascompte, Bartolo Luque, Jose Olarrea, Lucas Lacasa
Journal of Theoretical Biology 247, pp. 205-211 (2007)