With rapidly changing habitats and declining habitat quality, there is an urgent need to understand how long-lived large mammals adapt to extreme environmental changes. My research focuses on deciphering the proximate and ultimate causes of stress responses in large mammals, using Asian elephants as my primary study model. To investigate stress physiology, I use non-invasive methods, specifically, measuring glucocorticoid metabolites in faeces, to assess adrenal activity in free-ranging Asian elephants. This approach allows me to monitor stress without disturbing the animals. I have conducted extensive fieldwork across diverse landscapes in India to explore the mechanisms driving stress in elephants. My research has revealed that seasonal resource changes significantly affect body condition and stress reactivity in elephants. Social factors, such as the number of calves, the presence of lactating females, and group composition, can elevate glucocorticoid levels, highlighting the role of social stimuli in shaping stress responses. Challenging conventional assumptions, my work has shown that crop-foraging, usually perceived as stressful, can lower stress levels in elephants (in some landscapes!) by providing nutritional benefits. My work also includes proposing the Context-Experience-Personality model, which sheds light on the dynamic physiological responses observed in both Asian and African elephants. My ongoing research aims to unravel how different scales of anthropogenic disturbance affect various aspects of the physiological health of large mammals, including free-ranging Asian elephants, generating knowledge that informs conservation strategies for large mammals in rapidly transforming landscapes.

In collaboration with the Wildlife Research Center (Dr. Kodzue Kinoshita), Kyoto University, I developed a relatively novel technique to uncover the physiological histories of large mammals, with a focus on Asian elephants. We established that an elephant’s tail hair can act as a retrospective calendar, recording long-term stress patterns through cortisol analysis. This was the first study to use hair to trace stress markers in elephants, opening new avenues for non-invasive, long-term monitoring of their health. Building on this, under the Hakubi project, I aim to apply similar principles to the paleoecology of extinct proboscideans by exploring how preserved biological materials like hair and tusks can reveal the stress, diet, and life histories of these ancient giants. By connecting the physiological archives of living elephants with the fossil records, my goal is to understand how past proboscideans responded to environmental change, and what these insights can teach us about the future of today’s large mammals in a rapidly changing world.

Collaborative research

I am collaborating with Dr. Nachiketha Sharma, an elephant scientist who founded the Asian Elephant Comparative Thanatology Project (AeCT): the first dedicated initiative to systematically document how free-ranging Asian elephants respond to death within their social groups. Through this collaboration, we published some of the first scientific records describing the behavioural responses of wild Asian elephants to dying and dead conspecifics, providing rare and valuable insights into the thanatological (death-related) behaviours of proboscideans in the wild. Building on this pioneering work, we continue to jointly investigate these seldom-seen behaviours, aiming to deepen our understanding of how complex social and emotional processes have evolved in elephants. By documenting and analysing these responses across different contexts and herds, our ongoing research contributes new dimensions to elephant behavioural ecology and comparative thanatology. Refer media coverage for more details.

Collaborative research

I am also expanding my research on large mammal physiology through valuable insights gained from primate studies. Collaborating with Dr. Goro Hanya and his Primate Research Team at Kyoto University, we assess the digestibility and fermentation capacity of free-ranging Japanese macaques. This work investigated the fermentation ability of gut microbiota in wild macaques from both highland and lowland regions of Yakushima Island, using a combination of in vitro fermentation assays and genetic analyses. This comparative primate research provides an important framework for understanding how gut microbiota, nutrition, and habitat use shape physiological adaptations in long-lived mammals. It also offers a valuable reference point for exploring similar digestive and metabolic processes in large herbivores like elephants. I am initiating work on primate physiology, which will complement the search for the answer to the broader question of physiological adaptations. By bridging knowledge across taxonomic groups, from primates to elephants, I aim to build a broader, comparative perspective on how social structure, diet, and habitat conditions influence the physiological resilience of large mammals. Updates on this exciting new phase of primate endocrine research will be shared soon.

Other parallel collaborative research includes: understanding the human perceptions of ''conflicts" and the development of different field-based techniques.