Luis Y. Santiago-Rosario
Evolutionary Ecologist | Natural Historian | Postdoctoral Researcher Sarah Mathews Lab LSU
Interested in understanding how the environment influences phenotypic expression, especially in micronutrient stoichiometric mismatch and its role in adaptive phenotypic plasticity
A Little About Me
I reached a milestone in my career when I graduated with a Masters in Biology from the Inter American University of Puerto Rico and a Ph.D. from Louisiana State University under the guidance of Dr. Kyle E. Harms. I've always been interested in the connection between Eco-Evo-Devo, phenotypic expression, and plasticity. Recently, I've been focusing on how micronutrient availability, especially sodium, affects consumers' phenotypic expression and fitness consequences across a variable phytochemical landscape.
As a biologist who is proudly Puerto Rican, Latino, and queer, I hope to inspire the next generation to be open-minded in science and society.
My Research
The influence of sodium on behavior and mate choice
Sodium plays an essential role in the development of animals influencing osmoregulation, muscle development, and neural function. As herbivores, butterflies depend on their host plant for their nutritional needs, especially during larval states. I am focused on trying to understand what are the behavioral effects of variation in dietary sodium on survivorship For this project, I am using the sunflower specialist Bordered patch, Chlosyne lacinia (Lepidoptera: Nymphalidae), which is readily found in Southern Texas in sunflower patches. We found that at high plant sodium levels, larvae survivorship is diminished substantially due in part to salt-induced osmotic stress. However, at low levels of plant sodium, a proportion of larvae resorted to the cannibalism of their siblings, suggesting a significant influence of sodium on behavior. Stay for this article!
The image on the right shows the adult of Chlosyne lacinia resting on the remnants of a sunflower inflorescence in Southern Texas.
The phytochemical landscape of sodium
Sodium differs substantially across terrestrial habitats. For plants, sodium represents a problematic ion at higher concentrations that affect overall fitness and growth. However, for animals, sodium is essential. In this project, I focus on determining the relationship between sodium in the soil to the sodium available in sunflower (Helianthus), prickly pear (Opuntia), and saltbush (Atriplex) tissues across the Conterminous United States. You might ask what do these plants have in common? Very little. But they represent plants that differ in the photosynthetic pathways they use. Helianthus is C3, Atriplex is C4 and Opuntia is CAM. Each photosynthetic pathway deal with sodium in different ways.
The image on the right shows the prairie sunflower, Helianthus petiolaris, one of the species I used to assess sodium concentrations in plant tissues.
Consumer's phenotypic response to plant sodium stoichiometric mismatch
A stoichiometric mismatch or imbalance of chemical elements between what animals need and what they get from their food sources influences consumers' development and fitness. Indeed, the availability of sodium in the food source is no exception. Sodium is essential for muscle function, neural development, and osmoregulation in animals. Terrestrial animals encounter a high variation of sodium availability in primary producers. I am interested in the role of a varying sodium phytochemical landscape has on herbivore morphological and behavioral phenotypic development. I use sunflowers (Helianthus annuus) and the bordered patch butterfly (Chlosyne lacinia) in laboratory settings to understand the impact of dietary sodium on herbivore performance. Stay tuned for incredible and exciting results.
The image on the right shows male butterfly individuals puddling behavior at a moist salt source near the river Toro Negro in Ciales, Puerto Rico. Two species are seen in this picture, Phoebis argante martini (the Apricot sulphur) and Garyna josephina krugi (The Giant White).
Why do Australian showy mistletoes look so much alike?
Parasitic plants represent a unique opportunity to study species interactions and how these interactions influence the eco-evolutionary dynamics of phenotypic expression. Australian showy mistletoes (Loranthaceae) are unique because evidence suggests that some species appear to be 'mimicking' their host. Along with Sr. Sarah Mathews, we have been focusing on describing the level of phenotypic similarity there is by using computer vision. We are also investigating the host phylogenetic breadth of Australian showy mistletoes and how this relates to host specificity across native parasite genera.
The image on the left shows Amyema maidenii (Loranthaceae) near Alice Springs, NT, Australia..
Contact Me
103 Life Sciences Building
Louisiana State University
7875640500
Puerto Rican land carbs, Cardisoma guanhumi, shown in all its splendor. Here I just want to show my interest in macrophotography and texture.
