Alberto Corral-Lopez

SEXUAL SELECTION AND THE BRAIN

During my Doctoral thesis, I used guppy selection lines artificially selected for brain size and worked on the largely unexplored role that a larger brain plays in mating behaviour decisions of individuals through improved cognitive ability. This work naturally led to studies in guppies aimed at understanding the neurogenomic response of mate preferences in sensory and decision-making regions of the brain. Current and future work aims to incorporate the additional dimension that environmental variability in social and physical environments creates in the dynamic nature of behavioral decisions at the genomic level.

Research highlights:

Guppies artificially selected for relative brain size provided novel experimental support that individual variation in brain size affects mate choice decisions, i.e differences in cognitive ability may be an important underlying mechanism behind variation in female and male mating decisions.

Experiments with these selection lines across different predation pressure and operational sex ratio contexts provided evidence that brain size affect male guppy sexual behavioral patterns. Furthermore, they provide provide further evidence of a role for female brain size in optimal decision-making in a mating context.

We identified unique neurogenomic elements associated with the female mating decisions in comparisons of the transcriptional response between guppy females with and without preferences for colourful males. We showed that this response is highly centralized in the telencephalon of this fish , and identified gene drivers behind these behavioral neural processes

COLLECTIVE BEHAVIOR AND THE BRAIN

Understanding why and how animals gather in groups and coordinate their movements has always aroused great scientific interest. Indeed, we have to date accumulated strong evidence of selective forces acting on collective behaviors (e.g. predation pressure, foraging and travelling efficiency). However, understanding the mechanisms underlying the evolution of collective behavior has remained technically challenging. In my research, I assessed guppies artificially selected for higher coordinated motion with high-resolution computer vision tools, microcomputed tomography of brain anatomy, and multiple -omics tools to further our understanding of the mechanisms underlying the evolution of collective behavior.

Research highlights:

We found robust correlated changes in anti-predator response and sociability of guppy individuals selectively bred for higher coordinated motion, with changes in key brain regions and in the efficiency of social information transferring. These results provide novel evidence for brain anatomy as an important mechanism contributing to variation in collective behavior.

The development of tools for high-throughput behavioral phenotyping of individual fish when swimming in a school provided us a comprehensive dataset to evaluate the heritability of key behaviors in the evolution of collective motion. Furthermore, our results from DNA resequencing and transcriptomics comparing high- and low-sociability fish convergently implicated genes involved in social decision making through neuron migration and synaptic function. These results provide novel evidence of the crucial role that glutamatergic synaptic function and calcium-dependent signaling processes in the brain play in the evolution of collective behaviors.

COMPUTER VISION IN BIOLOGY RESEARCH

Context-dependent mate choice in guppies

The environment that individuals experience is a key driver in the maintenance of sexually selected traits, for instance through the effect of the social environment influencing mating decisions. Characterization of guppy sexual behaviour by means of high-throughput automated behavioural quantification provided evidence on the key effect of social learning in driving mating decisions. Further development of such methodologies promises an important avenue of research in the sexual selection field across multiple taxa.

Insect mimicry

I assesed flight patterns of neotropical damselflies and butterflies in natural habitats. Our findings demonstrated that the aposematic display of Polythoridae damselflies mimicking glasswing Ithomiini butterflies is multicomponent, consisting of coloration, morphology and locomotion. Further investigations of predator learning and avoidance of aposematic signals in this study system provided direct evidence for a stronger salience of wing coloration than wing morphology, and stronger selection pressure on imperfect than in perfect color mimics.

Personality in amphibians

I assesed risk-taking behaviors in an amphibian species across Scandinavian and northern European populations using automated behavioral quantification. Our findings demonstrated personality shifts between tadpole and metamorphic developmental stages in these populations because of antagonistic selective pressures that organisms with complex life cycles encounter across developmental stages.