I’m interested in reptile and amphibian responses to global change.
Historical spread of the fungal pathogen Batrachochytrium dendrobatidis (Bd) in the North American southwest region
Batrachochytrium dendrobatidis (Bd) is a fungal pathogen that has led to devastating amphibian declines worldwide. It causes chytridiomycosis, a skin disease that causes hyperkeratosis (thickened skin), which in turn impacts amphibians’ ability to regulate water, salt, and respiration (Berger et al. 1998). Because Bd thrives in aquatic environments and can spread rapidly through amphibian communities, entire populations have been wiped out from one introduction. While Bd is now known to infect more than 500 species of amphibians, its impacts are best characterized in species in regions where significant declines have occurred: Central and South America, Australia, and the Sierra Nevada mountains of California. I have collaborated with the Zamudio Lab under mentorship by Anat Belasen on multiple projects utilizing museomics to understand the historical spread of Bd.
Bd-associated leopard frog (Lithobates sp.) declines in Arizona
Leopard frogs (Lithobates sp.) in the southwest region of the United States experienced rapid declines and mass extirpations from the 1970s-1990s. In this study, we investigate the historic spread of Bd throughout Arizona from preserved museum specimens (1865-1995) of the Chiricahua leopard frog (L. chiricahuensis), Lowland leopard frog (L. yavapaiensis), and northern leopard frog (L. pipiens) and tie these to records of local extirpations. From our results, we re-evaluate the timeline and direction of Bd spread in Arizona over the 20th century.
Low historical Bd prevalence in black-spotted newts (Notophthalmus meridionalis) from Texas and Mexico
Due to their threatened status, Black-spotted Newts (Notophthalmus meridionalis) are of major conservation concern. In this study, we investigate whether Bd played a role in declines of Black-spotted Newts across their range. Using samples taken from historically collected newts (1939-1985), I tested for Bd presence using molecular Bd detection assays optimized for preserved museum specimens. This research contributes to knowledge of the effects of Bd on salamanders, and aids in informing salamander conservation efforts.
With the rise of genomic sequencing, the field of conservation genomics has grown rapidly and helped inform conservation of herpetofauna. However, the presence of global coldspots in genomic resources is limiting our conservation efforts in the regions most impacted by global change. We conducted a literature review to characterize the global distribution of genomic resources for amphibians and reptiles relative to species richness, IUCN status, and predicted global change. Our results highlight an urgent need for more robust genomic resources that specifically address adaptive potential, and call for equitable international collaboration and capacity building in the Global South.
While completing my undergraduate degree, I studied host-microbiome interactions in honey bees and aphids, and spider phylogeography.
In collaboration with Erick Motta in the Moran Lab, we explored the effects of caffeine on honey bees (Apis mellifera) with and without a gut microbiome, and how this could potentially impact susceptibility to Serratia marcescens, a bacterial pathogen. As a 4th-year undergraduate, I independently led the experiment for the study, keeping and monitoring bees.
In collaboration with Sarah Crews at the California Academy of Sciences, we investigate the genetic and morphological relationship between established species in the Selenops debilis group of spiders in the southwest region, exploring species differentiation through genetic analysis and reproductive morphometrics, leading to a greater understanding of the evolutionary history and species boundaries of this group.
Publications
5. Maeda, G. P., Dang, V., Kelly, M. K., Sundar, A., Arnott, R. L. W., Marcotte, E. M., Moran, N. A. Heritable symbiont producing nonribosomal peptide confers extreme heat sensitivity and antifungal protection on its host. PNAS 122(26): e2509873122. DOI: 10.1073/pnas.2509873122.
4. Carneiro, C. M., Shields-Estrada, A., Boville, A., Alves-Ferreira, G., Xu, T., Arnott, R. L. W., Allen-Love, C. M., Puertas, M., Jacisin, J. J., Tripp, H. C., Basham, E., Zamudio, K. R., Belasen, A. M. Toward a global science of conservation genomics: coldspots in genomic resources highlight a need for equitable collaborations and capacity building. Molecular Ecology e17729. DOI: 10.1111/mec.17729.
3. Arnott, R. L. W., Lopez, C. B., Rogers, M. N., Davis, D. R., Robinson, P. S., Kline, R. J., LaDuc, T. J., Zamudio, K. R., Belasen, A. M. (2024). Low historical prevalence of the fungal pathogen Batrachochytrium dendrobatidis in Black-spotted Newts (Notophthalmus meridionalis) from Texas and Mexico. Herpetological Review 55(3): 359-362. [PDF]
2. Motta, E. V. S., Arnott, R. L. W., Moran, N. A. (2023). Caffeine consumption helps honey bees fight a bacterial pathogen. Microbiology Spectrum 11(3): e0052023. DOI: 1128/spectrum.00520-23.
1. Powell, J. E., Lau, P., Rangel, J., Arnott, R., De Jong, T., Moran, N. (2023). The microbiome and gene expression of honey bee workers is affected by a diet containing pollen substitutes. PLoS ONE 18(5): e0286070. DOI: 1371/journal.pone.0286070.
