Criscione Lab

I examine fundamental ecological and evolutionary questions in parasite systems and consider my research to be at the interface of ecology, evolution, and genetics. Parasitology provides a rich subject area for studies of ecology and evolutionary biology. Numerous topics such as ecosystem dynamics, mating systems, or coevolution can be addressed because parasites are extremely diverse. By diversity, I include not only the myriad of taxa that have independently evolved a parasitic lifestyle, but also the diversity in life cycles, modes of reproduction, host species, and ecosystems utilized by parasites. This diversity also allows for comparative studies to address theories or unifying principles that span ecosystems or taxonomic groups. Furthermore, there are many practical applications such as studying the evolution of drug resistance, or using parasite community structure to assess “ecosystem health”. My research interests address both basic and applied questions, and span three overlapping subject areas: 1) Genetics and Ecological Genomics, 2) Evolution: Population Genetics, Mating Systems, and Molecular Epidemiology, and 3) Ecology: Biodiversity, Conservation, and Natural History.

Population Genetics, Mating Systems, and Molecular Epidemiology

Little is known about the genetic structure in parasite populations, much less what factors shape these patterns. Genetic structure can influence evolutionary outcomes such as speciation, adaptations to host defenses, and host adaptations to parasite virulence. For parasites of medical, veterinary, or commercial importance, genetic structure has important implications for the evolution of drug resistance and epidemiological models. My research integrates ecological principals in parasitology with population genetics theory to investigate evolutionary mechanisms that affect the genetic variation within and among parasite populations. A practical application that stems from my research is the use of population genetics methods to identify loci of transmission in human parasites (i.e., molecular epidemiology). Elucidation of parasite mating systems (e.g., selfing versus outcrossing) and factors that affect inbreeding in natural populations of parasites are other topics of interest.

Biodiversity, Conservation, and Natural History

The biodiversity and natural history of parasites in many systems remain uncharacterized. This is unfortunate because parasites can constitute a significant proportion of the biomass in an ecosystem, regulate host populations, alter individual host behaviors, and be an important component in food-web chains. Furthermore, many parasites have complex life cycles that require the use of invertebrate and vertebrate hosts. Thus, the presence of a parasite indicates that the required hosts are present in the ecosystem. Such knowledge on parasite community structure can be used to asses “ecosystem health”. A future goal is to establish a biodiversity/conservation research program that incorporates helminth parasite diversity in coastal wetland research around the Gulf of Mexico.

The direct interplay between parasites and their hosts enables reciprocal selective pressures that can shape underlying genetic variation in both parasites and their hosts. We are working to develop high quality reference genomes of the Mediterranean gecko, Hemidactylus turcicus, and one of its parasites, the cyclophyllidean tapeworm Oochoristica javaenesis. These genomic data will serve as the foundation to study the evolution of host immune loci and parasite loci that enable evasion or modulation of host immunity via various approaches: bioinformatics, transcriptomics, phylogenomics, and population genomics. Additional topics of study will include the effects of inbreeding on genome evolution (the tapeworm has high rates of self- and kin-mating), evolution of gene families in both the host and parasite, and genomics of invasive species (both the host and parasite are exotic species in the U.S.A.).

Lab News

August 2020
Congratulations to my PhD student Jenna Hulke who passed her prelims!!!

April 2020
My former PhD student, Dr. Mary Janecka, was awarded a NSF Postdoctoral Fellowship for her proposal entitled “Host-parasite coevolution against the current: How do river architecture, unidirectional drift and host behavior shape parasite coevolutionary potential?”

Congratulations!!!

March 2020
Check out our recent publication in PNAS “Clonemate cotransmission supports a role for kin selection in a puppeteer parasite”

See some of the press releases:

https://science.tamu.edu/news/2020/03/collaborative-texas-am-study-ties-kin-selection-to-host-manipulating-behavior-in-parasites/

https://phys.org/news/2020-03-evolution-life-parasitic-worm-zombie.html

https://www.sciencedaily.com/releases/2020/03/200310164735.htm

June 2019
Our paper on pentastome morphology was recently published in the Journal of Parasitology.

May 2019
Mary Janecka defended her dissertation! Congratulations Dr. Janecka! Mary will be doing a postdoc with Dr. Jessica Stephenson at the University of Pittsburgh.

Jan. 2019
Jenna Hulke joined the lab as a new PhD student. Welcome Jenna! Her research will examine the interface of parasite mating systems and complex life cycles using comparative population genetics.

Dec. 2018
Andrew Sakla completed his M.S.! Congratulations! He will be moving onto a Research Associate Position at UT Southwestern in Dallas

Charles Criscione
Professor
ccriscione@bio.tamu.edu

Department of Biology
TAMU 3258
College Station, TX 77843

Office: Butler 207A
Phone: 979-845-0917
Fax: 979-845-2891

Lab: Butler 207
Phone: 979-845-0925