We are examining patterns of parasite diversity across multiple geographic scales. The primary hosts we study, bivalves and seagrasses, are model organisms for this work. Both host groups include parasites with varying levels of host specificity, allowing us to examine the evolutionary, ecological, and genomic mechanisms that allow a parasite to infect many different host species.
Parasites are generally much smaller than their hosts, making them notoriously difficult to identify. Some of the larger metazoan parasites* can be viewed using a microscope. However, even most of these larger parasites require additional research tools for species-level identification. Thus, we primarily use DNA markers to identify parasites and examine their population genetic diversity* and structure. Some of the DNA tools we use include Sanger and high throughput sequencing* (454 and Illumina platforms), metabarcoding*, microsatellites*, and phylogenetics*.
Our work has examined the diversity of parasites in bivalves living along both coasts of Panama, leading to the discovery of an invasive oyster and many parasite species not previously known in these waters. This research is ongoing, as we continue to process bivalve samples that were collected over a latitudinal gradient to see how parasite diversity changes with latitude. We also examined the diversity of parasites throughout the environment in Panama, focusing on water and sediment samples collected around the Panama Canal, to see how much overlap exists across this corridor. Finally, we are examining the species and population genetic diversity of parasites associated with seagrasses in coastal waters, assessing the host specificity of these parasites in Florida and the genetic diversity of these parasites associated with the dominant seagrass in temperate waters, Zostera marina, across both US coasts.
As part of this research, we are also examining the ecology and epidemiology* of the infectious diseases caused by these parasites, which can range dramatically in severity across geographic locations and hosts.
Molecular Data Leads to Surprising Discoveries about Oysters in Panamanian Waters. By Katrina Lohan and Monaca Noble. May 2015
KM Pagenkopp Lohan, RC Fleischer, ME Torchin, and GM Ruiz (2017) Protistan Biogeography: A Snapshot Across a Major Shipping Corridor Spanning Two Oceans. Protist, 168: 183-196.
KM Pagenkopp Lohan, KM Hill-Spanik, ME Torchin, M Aguirre-Macedo, RC Fleischer, & GM Ruiz (2016) Richness and Distribution of Tropical Oyster Parasites in Two Oceans. Parasitology, 143: 1119-1132.
KM Pagenkopp Lohan, RC Fleischer, KJ Carney, KK Holzer, & GM Ruiz (2016) Amplicon-based pyrosequencing reveals high diversity of protistan parasites iships’ ballast water: implications for biogeography and infectious diseases. Microbial Ecology, 71 (3): 530-542.
KM Pagenkopp Lohan, KM Hill-Spanik, ME Torchin, EE Strong, RC Fleischer, & GM Ruiz (2015) Molecular phylogenetics reveals first record and invasion of Saccostrea species in the Caribbean. Marine Biology, 162: 957–968.