Guha Dharmarajan is a veterinarian and disease ecologist, whose research focuses on understanding the ecological and evolutionary dynamics of disease in natural populations. He obtained his Bachelor’s degree in Veterinary Science and Master’s degrees in Wildlife Science from the Madras Veterinary College, and his PhD in Wildlife Science from the Department of Forestry and Natural Resources at Purdue University. He carried out his postdoctoral research at Purdue and subsequently moved to the Laboratory of Malaria and Vector Research at the US National Institutes of Health (NIH). Following his postdoctoral research, he worked as a Ramanujan Fellow at the Indian Institute of Science Education and Research Kolkata. Before joining Krea, Guha was an Assistant Research Scientist at the Savannah River Ecology Lab, The University of Georgia.

Guha’s research is primarily in the fields of disease ecology and ecosystem health. Specifically, he studies how human-mediated environmental perturbations – global climate change, habitat modification and environmental pollution – affect disease dynamics in human and wildlife populations, and in turn how such altered disease dynamics feedback on ecosystem health by impacting eco-evolutionary processes at the individual, population and community scales.

Guha loves to teach, and has taught students at four institutions in India and the US (IISER-Kolkata, Krea University, Purdue University and the University of Georgia). At Krea, he teaches Scientific Reasoning, Biostatistics, Ecology and Conservation Biology, and Global Change Biology.

In his free time, Guha enjoys listening to a wide diversity of music from Hindustani Classical to Jazz. He also loves to read a broad array of fiction and non-fiction, but his favourite genre is epic fantasy.

Research

Disease Ecology and Ecosystem Health

Publications

Publications (Recent): 

• Dharmarajan G (2026) Effects of bias when using ‘black box’ models: re-evaluating the evidence for the use of name-like calls by elephants. Animal Behaviour 235: 123547. https://doi.org/10.1016/j.anbehav.2026.123547
• Fletcher DE, Spivey EA, Dirks JE and Dharmarajan G (2025) Copper accumulation through trophic vs direct water exposure routes in a dragonfly nymph/mosquito larvae laboratory food chain. Archives of Environmental Contamination and Toxicology 88: 277-288. https://doi.org/10.1007/s00244-025-01127-8
• Hill JE, Miller ML, Chipman RB, Gilbert AT, Beasley JC and Dharmarajan G, Rhodes OE Jr. (2025) Habitat-specific seasonal densities of sympatric raccoons and opossums in the Southeastern United States. Journal of Mammalogy 106: 683-691. https://doi.org/10.1093/jmammal/gyaf001
• Guo J, Zhao R, Li K, Tan A, Wang L, Ling A, Zhang H, Dharmarajan G, Bi Y, Yang R (2025) Altitude adaptation: The unseen work of gut microbiota. hLife 3: 5-20 https://doi.org/10.1016/j.hlife.2024.11.004
• Davis AJ, Dixon WC, Hill JE, Helton JL, Bernasconi DA, Chipman RB, Gilbert AT, Beasley JC and Rhodes OE Jr., Dharmarajan G (2025) Raccoon density estimation from camera traps for rabies virus management. The Journal of Wildlife Management e22701. https://doi.org/10.1002/jwmg.22701
• Pei S et al. (2025) Landscape ecological consolidations determine zoonotic host diversity in human habitats. Nature Ecology and Evolution 9: 99–110  https://doi.org/10.1038/s41559-024-02570-x
• Hill JE, Miller ML, Chipman RB, Gilbert AT, Beasley JC, Dharmarajan G and Rhodes OE Jr. (2024) Influence of habitat and baiting strategy on oral rabies vaccine bait uptake by raccoons in the southeastern United States. Applied Animal Behavior Science 277: 106320 https://doi.org/10.1016/j.applanim.2024.106320
• Bernasconi DA, Miller ML, Gupta P, Chipman RB, Gilbert AT, Beasley JC, Rhodes Jr OE and Dharmarajan G (2023) Raccoons (Procyon lotor) show higher Trypanosoma cruzi infection rates than opossums (Didelphis virginia) in the Southeast US. Journal of Wildlife Disease https://doi.org/10.7589/JWD-D-22-00174
• Dixon WC, Hill JE, Chipman RB, Davis AJ, Gilbert AT, Beasley JC, Rhodes Jr OE and Dharmarajan G (2023) Interspecific oral rabies vaccine bait competition in the Southeast United States. Applied Animal Behaviour Science 261,105897 https://doi.org:10.1016/j.applanim.2023.105897
• Frederick JC, Thompson AT, Sharma P, Dharmarajan G, Ronai I, Pesapane R, Smith RC, Sundstrom KD, Tsao JI, Tuten HC, Yabsley MJ and Glenn TC (2023) Phylogeography of the blacklegged tick (Ixodes scapularis) throughout the USA identifies candidate loci for differences in vectorial capacity. Molecular Ecology 32: 3133-3149 https://doi.org:10.1111/mec.16921
• Helton JL, Hill JE, Bernasconi DA, Dixon WC, Chipman RB, Gilbert AT, Beasley JC, Dharmarajan G and Rhodes Jr OE (2023) Assessment of habitat‐specific competition for oral rabies vaccine baits between raccoons and opossums. The Journal of Wildlife Management 87: e22398 https://doi.org:10.1002/jwmg.22398
• Hill J.E., Bernasconi, D.A., Chipman, R.B. et al. (2023) Home range and resource selection of Virginia opossums in the rural southeastern United States. Mammal Research 69: 193–204 https://doi.org/10.1007/s13364-023-00733-y
• Hill JE, Helton JL, Bernasconi DA, Dixon WC, Hamilton MT, Chipman RB, Gilbert AT, Beasley JC, Dharmarajan G and Rhodes Jr OE (2023) Raccoon densities across four rural habitats in the Southeastern United States. The Journal of Wildlife Management 87, e22480 https://doi.org:10.1002/jwmg.22480
• Hill JE, Helton JL, Chipman RB, Gilbert AT, Beasley JC, Dharmarajan G and Rhodes Jr OE (2023) Spatial ecology of translocated raccoons. Scientific Reports 13: 10447 https://doi.org:10.1038/s41598-023-37323-6
• Hill JE, Miller ML, Helton JL, Chipman RB, Gilbert AT, Beasley JC, Dharmarajan G, Rhodes OE Jr. (2023) Raccoon spatial ecology in the rural southeastern United States. Plos One 18: e0293133 https://doi.org/10.1371/journal.pone.0293133
• Bernasconi DA, Dixon WC, Hamilton MT, Helton JL, Chipman RB, Gilbert AT, Beasley JC, Rhodes Jr OE and Dharmarajan G (2022) Influence of landscape attributes on Virginia opossum density. The Journal of Wildlife Management 86: e22280 https://doi.org/10.1002/jwmg.22280
• Dharmarajan G, Li R, Chanda E, Dean KR, Dirzo R, Jakobsen KS, Khan I, Leirs H, Shi Z-L, Wolfe ND, Yang R and Stenseth NC (2022) The animal origin of major human infectious diseases: What can past epidemics teach us about preventing the next pandemic? Zoonoses 2: 11 https://doi.org:10.15212/zoonoses-2021-0028
• Dharmarajan G, Gupta P, Vishnudas CK and Robin VV (2021) Anthropogenic disturbance favours generalist over specialist parasites in bird communities: Implications for risk of disease emergence. Ecology Letters 24, 1859-1868 https://doi.org:10.1111/ele.13818 [Cover Article]
• Fecchio A, Clark NJ, Bell JA, Skeen HR, Lutz HL, De La Torre GM, Vaughan JA, Tkach VV, Schunck F, Ferreira FC, Braga ÉM, Lugarini C, Wamiti W, Dispoto JH, Galen SC, Kirchgatter K, Sagario MC, Cueto VR, González‐Acuña D, Inumaru M, Sato Y, Schumm YR, Quillfeldt P, Pellegrino I, Dharmarajan G, Gupta P, Robin VV, Ciloglu A, Yildirim A, Huang X, Chapa‐Vargas L, Álvarez‐Mendizábal P, Santiago‐Alarcon D, Drovetski SV, Hellgren O, Voelker G, Ricklefs RE, Hackett SJ, Collins MD, Weckstein JD, Wells K and Kamath P (2021) Global drivers of avian haemosporidian infections vary across zoogeographical regions. Global Ecology and Biogeography 30, 2393-2406 https://doi.org:10.1111/geb.13390
• Seal S, Dharmarajan G and Khan I (2021) Evolution of pathogen tolerance and emerging infections: A missing experimental paradigm. eLife 10, e68874 https://doi.org:10.7554/eLife.68874
• Stenseth NC, Dharmarajan G, Li R, Shi ZL, Yang R and Gao GF (2021) Lessons learnt from the COVID-19 pandemic. Frontiers in Public Health 9, 694705 https://doi.org:10.3389/fpubh.2021.694705
• Street GM, Potts JR, Börger L, Beasley JC, Demarais S, Fryxell JM, McLoughlin PD, Monteith KL, Prokopenko CM, Ribeiro MC, Rodgers AR, Strickland BK, van Beest FM, Bernasconi DA, Beumer LT, Dharmarajan G, Dwinnell SP, Keiter DA, Keuroghlian A, Newediuk LJ, Oshima JEF, Rhodes Jr OE, Schlichting PE, Schmidt NM and Vander Wal E (2021) Solving the sample size problem for resource selection functions. Methods in Ecology and Evolution 12, 2421-2431 https://doi.org:10.1111/2041-210x.13701

Teaching Modules

Scientific Reasoning

Biostatistics

Ecology and Conservation Biology

Global Change Biology