I am interested in the patterns of species distributions and the processes behind the generation and persistence of those patterns. I graduated with a BS in Biology from Universidad de los Andes in Bogotá, Colombia where I studied the phylogeography of the Red-eyed tree frog. During my MSc at the same university, I studied the environmental and ecological determinants of population genetic divergence in amphibians of Panama. I am considering phylogeography, species distribution models and the physiological aspects of organisms to understand species range limits. For this work, I was awarded a Fulbright Colombia fellowship. Since 2015, I am a Biology, EEB PhD student at CUNY in the Carnaval Lab.

Project

My work combines physiological assays with a population genomic analysis of four species of frogs (endemic to South America). Specifically, I test whether there is inter- and intra-specific variation in thermo-physiological traits, and whether this variation is associated with elevation and demographic responses to past climate change inferred with genomic-scale data. For this, I am estimating species-critical thermal maximum and minimum, and comparing these results with temperatures experienced by these species in their distribution to assess congruence. Furthermore, I am considering the relation between climatic variability, elevational ranges, and physiological tolerances. Based on DNA samples of these individuals and others collected by my collaborators, I use a ddRADseq method to obtain restriction-site associated genomic-level data. I will then analyze the molecular data 1) to observe the geographical patterns of genetic diversity, 2) to determine the number of populations within each species, and whether they have different thermal-physiologies, and 3) to test for synchrony in the demographic expansion of these species in response to known environmental shifts.

As I was growing up in the tropics, I remember always being surrounded by more species of animals and plants that I could name and the animals I could see completely changed in a few hours of a road trip. Later, as a biologist, I learned that this is true at the highest scientific level, we only know about ten percent of the world’s species and most of these undescribed and poorly understood species are found in tropical areas. In my dissertation, I want to improve the predictions of biodiversity patterns in geographical space and over time. For that, I am working on a study at different scales (from a continental to a local scale and from several species and groups to a single group of amphibians) to understand the environmental drivers of biodiversity patterns in species from the tropics. I have four chapters that start with a large geographical scale and several species end with a single group, the amphibians in the coastal mountains of Brazil (highlands of the Atlantic Forest) and the northern Andes in South America. 

The work I undertook this summer focused on understanding the historical population processes that may lead to current observed distributions of amphibians, the focus of my fourth chapter, specifically four species of frogs in South America. I want to understand the distribution of these species and their genetic variation and how they relate to the environment, both today and in the past. They are high elevation species that like the cold temperatures and were very common 21,000 years ago, but are becoming scarcer in our warmer times. To answer my questions, I require DNA information that will allow me to understand the past responses to these frogs to environmental changes in term of changes in population sizes. During the summer, I performed DNA extractions for 52 individuals of two species of frogs endemic to the Brazilian Atlantic Forest. These samples were collected by some of my collaborators in Brazil, but I went to Brazil to bring some of them back. After quantifying the amount of DNA in the extractions, I deemed most of them successful. This is a great start for one my dissertation chapters, in which I aim to compare the population history of frogs in the Atlantic Forest and the Northern Andes of South America. My next steps include doing some genomic sampling of these individuals with a technique called restriction site-associated DNA sequencing, more commonly known as RAD-seq. I am waiting to bring the samples for the two species of amphibians that I collected in Colombia last October to send all of them together for sequencing.