The Ecology and Genomics of Medically Significant Snakes of the Indian Subcontinent

Abstract

Snakebite Envenomation (SBE) is a global health crisis with rural communities in tropical regions of world the most affected. India has the unenviable label of being the snakebite capital of the world with an estimated 58,000 fatalities every year. A critical aspect when understanding SBE in India that is overlooked is the ecology and genomics of the medically significant species. Here, the thesis focuses on novel methods to understand the ecology of snake-human conflict and the genomics of the most medically significant species of India. Using 520 snake rescue encounters recorded by a community network in Hooghly District, West Bengal (July 2020–October 2022), I demonstrate that rescue data can capture fine-scale patterns of snake–human interaction that are directly relevant to prevention, including seasonal trends, site-specific risk, and associations with local climatic patterns (Chapter 2). I then provide the first comparative population-genomic baseline for the Indian “Big Four” (Naja naja, Daboia russelii, Bungarus caeruleus, and Echis carinatus) using low-coverage whole-genome data analysed with genotype-likelihood methods, resolving geographically structured lineages (north–south splits in N. naja and D. russelii, and a third western lineage in B. caeruleus and E. carinatus) and characterising the gene flow between the populations of each species, thereby defining potential evolutionary units for future venom, clinical, and antivenom comparisons (Chapter 3). Finally, we produce a chromosome-scale Sri Lankan N. naja genome assembly from minimally invasive ventral scale clips (Chapter 4). We benchmark it against a published Indian N. naja reference assembly and identified structural variants within and near the loci of major toxin gene families despite a broader chromosomal collinearity between the two assemblies. Together, these chapters show how community-embedded monitoring, population structure, and reference genomes can be integrated to prioritise where to sample, and which genomic mechanisms may contribute to clinically relevant venom diversity in South Asia. These chapter show that in order to reduce the burden of SBE, it needs to be seen as an ecological-evolutionary as much as a clinical one.

Date of Award	28 May 2026
Original language	English
Awarding Institution	Bangor University
Supervisor	Anita Malhotra (Supervisor), Axel Barlow (Supervisor) & Aaron Comeault (Supervisor)