Macroevolution | Evolutionary Biology | Functional Morphology
Below are short descriptions of multiple ongoing research projects, which generally pertains to the evolutionary biology, ecology, and behavior of Neotropical cichlid fishes, Caribbean anole lizards, and North American salamanders.
Parallel evolution and ecological speciation in pike cichlids (Crenicichla)
Crenicichla are a unique radiation of South American cichlids that are elongate predators. My collaborators and I are using phylogenomics (UCEs and ddRADseq) to evaluate Crenicichla phylogeny and population genetics. Secondly, I am interested in the parallel evolution of similar sets of ecomorphs in the Paraná and Uruguay Rivers. These two clades have independently and rapidly evolved several ecomorphs, including species that crush molluscs with hypertrophied pharyngeal jaws, others that pry clinging invertebrates from rock crevices with hypertrophied lips, and yet others that graze periphyton with compact benthic-oriented oral jaws.
Read more about this project here.
Thumbnail: Representatives of the Iguazu (left) and Uruguay (right) River species flocks. Paintings by Rene P. Martin.
Macroevolutionary features of adaptive radiation
I am interested in theory about adaptive radiation - how and why it occurs, what it looks like, how to detect and quantify patterns and underlying processes. More specifically, how different sources of ecological opportunity - extinction of competitors, evolution of a key innovation, or colonization of a novel environment - influence morphological, ecological, and species diversity. I mostly use phylogenetic comparative methods, but also ecology and life history, to study both model and non-model groups. My research principally involves cichlids, but also North American minnows and marine fishes. The co-evolution of form and function, particularly the oral and pharyngeal jaws, and testing classic adaptive radiation hypotheses (i.e., time-dependent diversification) are a major focus.
Read more about cichlids here.
Thumbnail: Radiographs of several cichlids, depicting their diversity, radiographed by E.D.B. with assistance from Sandra Raredon at the Smithsonian Support Center.
Ecological and evolutionary implications of the oral and pharyngeal jaw systems in ray-finned fishes
I am interested in many aspects of jaws. How do they function? How have they evolved? Ray-finned fishes have two jaw systems - oral and pharyngeal jaws - that provide a versatile feeding apparatus. I am interested in how these jaw systems respond to feeding ecology and the degree of functional and evolutionary integration between the jaw systems.
Thumbnail: lower pharyngeal jaws of several Neotropical cichlids depicting the diversity of shape and dentition, dissected and photographed by E.D.B.
Macroevolutionary consequences of trade-offs
A central part of my postdoctoral work in the Muñoz Lab deals with trade-offs, including the jaw system of fishes and limbs of lizards and salamanders. My primary interest is how trading-off influences the rate of phenotypic evolution, especially (1) if trading-off acts as a constraint or promotor of diversification, (2) if the effect is symmetrical (or asymmetrical) along the trade-off, and (3) if the effect varied according to the extent to which a trade-off is explored.
Collaborators: Martha Muñoz
Thumbnail: A red salamander (Pseudotriton ruber) along a tributary to Halawaki Creek, Alabama, USA, photographed by E.D.B.