Ana Castillo-Páez

Who I am

I became acquainted with the sea when I was 15 years old. When I dived in and found a world full of colour and life in the ocean, I knew at once that I wanted to spend my life in it. It was amazing. From that moment I began to look for information and read everything about it. I graduated in marine biology and worked in elasmobranch fisheries on Colombia’s Caribbean coast for my Bachelor’s thesis. Then, for my Master’s, I chose the course in molecular ecology, even though it was considered terrifying. I loved it. Since then my two passions have been interwoven in my work: genomics/transcriptomics and rays and other vertebrates and invertebrate marine organisms of the Mexican Pacific.

Where I work

I have been spending the past few years in a wonderful place with great marine diversity: the subtropical and tropical regions of the Pacific coast of Mexico. They are characterised by interesting oceanographic patterns that can be correlated to diverse ecosystems. The Sea of Cortez, located in the north of Mexico, is a semi-enclosed ecosystem and is considered by many international scientists to be a natural laboratory. The Gulf of Tehuantepec, in Mexico’s south, has very different marine species. Between these two geographical points, we find some species associated with the cold water of the California Current and others associated with the warm water of the tropical current. This results in very interesting patterns of diversification, even in megafauna such as sharks and rays.

What I do

The accurate identification of species is critical for our attempts to protect and conserve them. It has been reported that some species show morphological variation in different parts of their distribution range. As a consequence of this, two individuals of the same species but with different morphology could be erroneously classified as distinct species. Conversely, there are species whose morphological characters converge and they could be classified as a single species. In other words, two morphologically identical individuals could be two different species. In addition to recording and measuring the morphological characteristics of individuals, we analyse some regions of the genome to correctly identify the species. So we spend a lot of time in the lab working on things that are invisible to the eye but still have a lot to tell us – the amazing world of DNA. Then, when we have the results of the lab processes, we spend fun analytical time in front of our computers, trying to work out the relationships between individuals.