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Phylogenetic Systematics
As an ichthyologist, one of my primary interests is untangling the evolutionary relationships of diverse fish clades. Much of my dissertation research involved the use of molecular data to reconstruct the phylogeny of electric fishes in the family Apteronotidae.
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Taxonomy
The Neotropics are home to one of the most diverse fish faunas on earth with over 6000 described species. This number continues to increase with dozens of new species described each year. Over one third of the 96 species in the family Apteronotidae have been described since 2007. With the rapidly growing threats of habitat loss (e.g. due to dams or deforestation), it is critical to document and catalog this imperiled diversity. Taxonomy is an integral part of my work and I rely on both traditional morphogical as well as genetic data in the description of new species.
The Neotropics are home to one of the most diverse fish faunas on earth with over 6000 described species. This number continues to increase with dozens of new species described each year. Over one third of the 96 species in the family Apteronotidae have been described since 2007. With the rapidly growing threats of habitat loss (e.g. due to dams or deforestation), it is critical to document and catalog this imperiled diversity. Taxonomy is an integral part of my work and I rely on both traditional morphogical as well as genetic data in the description of new species.
![Picture](/uploads/1/2/0/2/120202026/published/fig1.jpg?1536870051)
Historical Biogeography and Ecology
One major goal of my work is to map the evolution of fishes through time and space in order to assess the geologic and ecological factors that may influence or shape diversification. By using time-calibrated phylogenies and ancestral range estimation, I am able to visualize the spatial context of evolution which allows me to assess the role of major geologic events (e.g. the rise of the Eastern Cordillera or the formation of the modern Amazon River) in generating the diversity of the present. Similarly, the use of ancestral state estimation models allows the characterization of major transitions in habitat throughout a clade's history.
One major goal of my work is to map the evolution of fishes through time and space in order to assess the geologic and ecological factors that may influence or shape diversification. By using time-calibrated phylogenies and ancestral range estimation, I am able to visualize the spatial context of evolution which allows me to assess the role of major geologic events (e.g. the rise of the Eastern Cordillera or the formation of the modern Amazon River) in generating the diversity of the present. Similarly, the use of ancestral state estimation models allows the characterization of major transitions in habitat throughout a clade's history.
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Fieldwork/Collections
Field collections have been essential to my research. My sampling efforts have primarily targeted deep river channels in the Neotropics using trawls and purse seines. Deep channels have historically been an undersampled habitat, but they are often the source of exceptional diversity. In addition to generating museum specimens and distributional data, a central objective of my fieldwork has been the collection of tissue samples for genetic and stable isotope analyses.
Field collections have been essential to my research. My sampling efforts have primarily targeted deep river channels in the Neotropics using trawls and purse seines. Deep channels have historically been an undersampled habitat, but they are often the source of exceptional diversity. In addition to generating museum specimens and distributional data, a central objective of my fieldwork has been the collection of tissue samples for genetic and stable isotope analyses.
![Picture](/uploads/1/2/0/2/120202026/published/img-3030.jpg?1537160258)
Morphological Evolution
In addition to dramatic species-richness, the Neotropical fish fauna also exhibits a remarkable diversity in novel phenotypes. In my study taxon, the ghost knifefishes, there is a wide range of cranial morphology presumably associated with divergence in trophic ecology. This clade is also shows striking intraspecific disparity in the form of sexual dimorphism, with males of some species growing greatly elongated snouts or enlarged teeth. A first step in studying these unique phenotypes is descriptive osteology using both traditional methods and micro-computed tomography (micro-ct). Additional analyses seek to integrate morphological and phylogenetic data in order to study the distribution of novel phenotypes and to explore their evolution in a temporal context.
In addition to dramatic species-richness, the Neotropical fish fauna also exhibits a remarkable diversity in novel phenotypes. In my study taxon, the ghost knifefishes, there is a wide range of cranial morphology presumably associated with divergence in trophic ecology. This clade is also shows striking intraspecific disparity in the form of sexual dimorphism, with males of some species growing greatly elongated snouts or enlarged teeth. A first step in studying these unique phenotypes is descriptive osteology using both traditional methods and micro-computed tomography (micro-ct). Additional analyses seek to integrate morphological and phylogenetic data in order to study the distribution of novel phenotypes and to explore their evolution in a temporal context.