Panama has captured my heart. It is only the first week. We have capitalized on our short time since arrival and have experienced a snapshot of the rich and biologically diverse systems under active study on BCI and in Gamboa. Galvanized by each of our experiences, I couldn’t choose just one. It’s been delightfully crazy and full of exciting science.
The first day was populated with several talks beginning with Dr. Anthony Coates who commenced my immersive learning with an overview on the history of Panama from a geologically focused perspective. Quickly following Dr. Coates’ presentation, we headed to Barro Colorado Island (BCI) for a multiple day excursion where several projects were presented on tropical forest ecology and plant-pathogen/herbivore interactions by Drs. Erin Spear, Scott Managan, Camilo Zalamea, and Scott Sedio. In previous years, the field course has been about exploring the biodiversity of Panama with walk and talks. However, this year the course has been structured so that students spear-head small-scale projects during each segment to gain and understanding of project and experimental design in the Neotropics. I chose to work with community chemical ecologist Brian Sedio on BCI because of his previous work and interest in plant-herbivore ecology. His recent work compared phylogenetic relatedness of piper and psychotria plants to their chemical composition. For the next 27 hours, my group of like-minded students (for the purpose of this project) sequestered ourselves in a world of piper plants, insect specimens, and treacherous tropical forests. We decided to test if Piperaceae herbivore presence correlated with secondary chemical compounds or the phylogenetic similarity of individual species, and we predicted that chemical compounds would better explain herbivore species presence than phylogeny. We identified all the piper species in 20 plots of 6 meters, inspected the leaves for large insects, and then aggressively shook the plants onto beating sheets to collect the remaining herbivores (predominantly weevils and beetles). While I sorted and identified insects (due to a preexisting interest in entomology), others were entering data and using the R package Picante to integrate Dr. Sedio’s previous phylogenetic and chemical data with our own. Our results suggested that herbivory is not directly affected by chemical niche, however much of that could be due our sample size, the methods we used, and the season we collected i.e. dry vs. wet.
We returned to Gamboa on Friday morning, and I promptly caught a cold (lame). Dr. Ehab Abouheif from McGill University directed us in a collective project to identify the (morhphological) subcaste distribution of Atta cephalotes leaf cutter ants who have 8 morph subtypes. We collected 4 chambers from 3 colonies in ethanol and sorted them by head size back at he STRI field house. Ultimately our distribution was heavily biased towards the larger end of the spectrum due as a result eaof easier specimen collection by tweezers. Dr. Abouheif later presented his work on the highly conserved genes that control development and the epigenetic role in the field of eco-evo-devo. He showed how the development and evolution of quantitative variation within any colonies and how genes that control development are often highly conserved in expression and function, such as DNA methylation which suppresses the expression at specific times to regulate caste differentiation. Dr. Abouheif presented his work on EGFR’s role in growth and size and how it results in variation in behavior and morphology (Alvarado et al. 2015). He also discussed his work on inducting super soldiers as a model for genetic accommodation (Rajakumar et al. 2012). Despite my cold, it was a fantastic day filled with hymenopteran genomics.
Saturday we went to San Lorenzo to go up in the canopy crane and practice catching Heliconius butterflies, a process that is much less glamorous than the study organism itself. It was a windy day so both endeavors were not terribly successful, though we had a lovely sack lunch together on a patch of grass. In the evening, Dr. Paul Frandsen, STRI research data scientist, discussed his work on “big data” insect phylogenetics and how different models are used to resolve the phylogenies of species’ with convoluted taxonomy. He is a contributor to the 1KITE project and discussed the genomic resource importance of such large scale, highly computational, and collaborative sequencing projects.
Incorporating more policy geared concepts into the course curriculum, Dr. Brian Leung from McGill University discussed how he applies mathematical models to invasion biology with limited knowledge of the invasive species that negatively impact the native ecology. He used a lot of numbers and symbols that I didn’t really understand. On the same evening we went to Gamboa Bat Night, where there were different stations set up to discuss mist netting, species diversity, echolocation, and vampire bat social dynamics. There is a team here who studies that motivating factors of food sharing between vampire bats: kinship, bet-hedging (in the event that the donor falls on hard times), previous feeding, etc.
It’s already been an amazing experience, and I am very grateful for the opportunity to meet such a diverse group of scientist. I had the nice surprise of finding two stingless bee nests that I hope to use in my short project. More to come on that later…