Macroecology and evolution of migration in fishes

Migrations contribute in shaping the current distribution of species on Earth. Transitions from residency to the propensity to migrate depend both on historical constraints and environmental conditions. Fishes provide an excellent system to test different hypotheses given their diversity, distribution and variety of migratory tactics. This work explored different facets of the evolution and ecology of migration in fishes.

Coastal habitats in Chile are hypothesized to support a number of migratory fish species and, using otolith microchemistry, I documented different life histories of native and exotic fishes discussing the role of environmental heterogeneity coupled with migration propensity in promoting colonization of new habitats.

The interaction of different variables such as environmental productivity, energy, heterogeneity, and phylogenetic structure in explaining the global diversity of migratory fishes was also explored using path analysis. The role of phylogenetic propensity in selected taxa to undertake migrations and their dependence on seasonal environments was suggesting that some migrating fishes may have had different patterns of diversification history which were then explored analyzing differences in speciation rates across latitude and given different life-history scenarios (residents versus migrants). Results show that, with some exceptions, migratory species display patterns of faster diversification rates compared to resident species.

Additionally, there is evidence that speciation rates are higher at lower latitudes as predicted from the diversification rate hypothesis. More research is needed to further deconstruct the different interacting roles of life history, evolution and ecology in shaping the distribution of life on Earth.

• Nombre: Dominique Alò
• Laboratorio: Macroecología
• Mención: Ecología
• Director Tesis: Pablo Marquet