Research

We study evolutionary ecology in a variety of organisms, including bird, fishes and insects

Some specific projects include:

Adaptive divergence and speciation

Some of our research focuses on understanding the micro-evolutionary processes that determine adaptive diversification in natural populations. For instance, we study how ecological differences can promote and maintain morphological and genetic divergence within populations and among species of Darwin's finches.

Divergent beak-size morphs within the medium Ground finch, G. fortis, on Santa Cruz Island. My research suggests that these two morphs may be undergoing initial stages of divergence within a single island. © L. F. De León.

Human impacts on evolution

This research project asks how anthropogenic disturbances can affect the initial stages of adaptive divergence, and in particular, how humans can impact the adaptive landscapes that maintain the boundaries between populations or species. We have found evidence for this processes in Galápagos Islands where the introduction of novel food resources by humans seems to be hampering adaptive divergence within the medium Ground finch. More recently, we have found that urbanization is eroding the ecological differences that drive diversification in Darwin's finches.

Darwin's finches can exploit novel human food items. For instance, this medium Ground finch was photographed while eating rice from a feeder in Puerto Ayora, Santa Cruz Island. My research suggests that humans could be affecting the process of adaptive radiation in Darwin's finches. © L. F. De León.

Eco-evolutionary dynamics

So far, our research has mostly focused on how ecological changes influence evolution in natural populations. However, we are also interested in the opposite effect: how do evolutionary changes influence ecological dynamics? This interaction between ecology and evolution is known as eco-evolutionary dynamics, and is the focus of my ongoing research looking at the interaction between finches and plant communities.

The granivorous Ground finches evoke Darwin's words “...from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.” Charles Darwin 1839, The Voyage of the Beagle, p328.

Genomics of diversification in weakly-electric fishes

Electric fishes produce a bioelectric field through the discharge of an electric organ (EOD). These fields are used to localize objects and prey, and are involved in mating and social interactions. This project attempts to understand the factors shaping these electric fields, and their role in determining evolutionary trajectories and diversification in these fresh water species. We also use next generation sequencing tools to determine the genomic consequences of diversification in electric fishes.

Brachyhypopomus occidentalis from Panama. © L. F. De León.

Other organisms we study

Neotropical water striders

Gasteropelecus maculatus Steindachner, 1879

Roeboides occidentalis Meek & Hildebrand, 1916

Introduced Guppy (Poecilia reticulata) populations from Panama

Astyanax ruberrimus Eigenmann, 1913

A typical river from the Caribbean slope of Panama.