I use a multidisciplinary approach, combining behavioural, neural, physiological, chemical and genetic techniques to address evolutionary and conservation questions. Currently, I am developing a multidisciplinary and integrative program on urban ecology and evolution, combining field and laboratory studies. Urban ecology is becoming a very important field of research, due to the continuous expansion of urban environments and the increasing number of species that may be affected by urbanization. Animals living in urban environments are exposed to a series of stressors, such as: air pollution, noise, light pollution, toxins and new diseases. Unfortunately, we know very little about how all these urban stressors may affect the fitness of these species. There is also a growing concern about the health of humans living in cities. The overall objective of my research program will be to understand how urban species may be adapted to the environmental challenges of living in cities, and why other species may not thrive in such environments. I will study how urban stressors affect the behaviour, brain development, genetic composition and reproduction of animals living in urban environments, with a focus on rodents. Some hypotheses that I want to investigate are (a) whether genetic changes in urban animals allow them to cope with their new environment; (b) whether reproduction is negatively affected by urban stressors; (c) whether chemical and vocal communication in urban mammals are affected by pollutants, noise, and the altered physical and social environments; and (d) whether increased demands on spatial learning and changes in social environment lead to behavioural and neural changes in urban animals.
A general theme of my past research has been the interface between chemical communication and sexual selection. As a PhD student, I investigated sperm competition (which occurs when a female mates with two or more males and the sperm of those males compete to fertilize the female’s eggs) from a novel perspective (chemical communication). This work demonstrated that male voles use olfactory information to assess different contexts of sperm competition and respond accordingly, mainly by adjusting the number of sperm allocated in their ejaculates.
My interest in chemosensory signalling continued as a postdoc at Cornell University, where my research focused on interspecific interactions between two closely related species, the Syrian and Turkish hamsters (Mesocricetus spp). I determined that receptive female hamsters show a preference for odours of conspecific males, and that a brain area (the medial amygdala) is involved in this type of preference in receptive female hamsters. Despite this discriminatory ability, females that have never been exposed to heterospecifics readily mate with heterospecific males. However, I found that female hamsters learn to avoid mating with heterospecific males after long-term exposure to them. This shows that in some species the avoidance of interspecific mating may require learning during adulthood.
During my second postdoc at Duke University I studied olfactory communication in several prosimian species housed at the Duke Lemur Center. I compared the chemical and protein composition of scents in these prosimian species, using GC-MS techniques in association with multi-dimensional statistics. I found that species that use urine as their primary source for olfactory communication have more volatile compounds in their urine than species that do not rely in urine but in glandular secretions for olfactory communication. I also determined that chemical signals in prosimians evolve at high rates and follow a gradual mode of evolution. In addition to my research on the evolution of chemical signals in primates, I conducted field research in the Kalahari Desert to determine the role of testosterone in mediating social interactions among subordinate male meerkats. We used flutamide implants to block the activity of testosterone in the brain and found that testosterone does not only affect aggression but also prosocial behaviours and the expression of playing behaviours among subordinate males.
At the Museo Nacional de Ciencias Naturales (a main institute of the Spanish Research Council, CSIC), I used a comparative approach to understand the effect of sexual selection on reproductive physiology. More specifically, I studied the role of sperm competition in the evolution of reproductive traits in several species of mice. I addressed the general hypothesis that increased levels of sperm competition lead to higher ATP production to fuel higher sperm velocities, and that such a heightened metabolism increases the production of reactive oxygen species (ROS) and thus the risk of oxidative damage. For example, I found that in species with high levels of sperm competition there is a dramatic decrease in the proportion of polyunsaturated fatty acids that are most prone to lipid peroxidation in the sperm membrane.
General Topics of Interest: Evolutionary Biology, Behavioural Ecology, Urban evolution, Urban ecology, Olfactory communication, Chemical Ecology, Sexual selection, Sperm competition, Reproductive Behaviour, Reproductive physiology, Neuroethology, Mammals, Rodents