Members

Lab Head

Dr. Aniruddha Datta-Roy


The contemporary distribution of biota within the Indian subcontinent must have been shaped by its unique history. The Indian subcontinent was part of Gondwanaland and had close tectonic associations with Africa, Madagascar and Seychelles before eventually colliding with Eurasia, resulting in the orogenesis of the Himalayas. The initial contact of the Indian plate with Southeast Asia may have potentially resulted in an exchange of biota across these two landmasses. On the other hand, the contemporary Indian subregion remains insular from other biogeographic zones areas owing to various geographic barriers. Prolonged insularity generally promotes diversification in lineages with limited dispersal ability, resulting in endemic radiations. Beyond bearing these unique spatial and temporal signatures in its biotic assembly, the Indian subcontinent is heterogeneous in its topography, with about ten major river systems/ basins flowing out of the peninsula. Furthermore, the Indian subcontinent has about six major hill ranges. Cumulatively, these factors would have had (or still have) a significant effect on the contemporary distribution of biota within the Indian subcontinent, resulting in an interesting mix of lineages. Indian biota may therefore be composed of ancient Gondwanan relicts to lineages that dispersed more recently from other regions. I am interested in South Asian herpetofauna (reptiles and amphibians), largely due to their diversity and antiquity. However, in my lab, we have broad interests ranging from understanding systematics, biogeographic patterns, and the evolution of characters in a diverse range of taxa from the Indian subcontinent. As a lab PI, I want to maintain and inculcate a keen interest in organismal biology, ecology, natural history, systematics, and biogeography.

Post-doctoral Fellows

Maitreya Sil

I have joined the lab as a Postdoc to understand the evolution of different color morphs in Indrella ampulla, an endemic land snail species from Western Ghats, India. I am primarily going to use genomic tools to address various questions pertaining to this topic. Previously I have investigated the historical biogeography, phylogeography, speciation, and taxonomy of several snail genera. During my last postdoc, I also explored questions concerning the conservation genomics of Asian elephants. Outside my work, I am interested in exploring nature, and the literature and cuisine from various parts of the country and beyond.

PhD Students

Avrajjal Ghosh

Reptiles and Amphibians have fascinated me since childhood and I have always wanted to study intricacies associated with them. How these enigmatic animals came to occupy their current distributional range has always intrigued me and for my Ph.D., I am adhering to my interest and studying a highly speciose group of small, shiny lizards called skinks (Family: Scincidae). I am particularly interested in exploring speciation and dispersal patterns among three genera of South Asian skinks- Kaestlea, Ristella, and Subdoluseps. Members of the genus Kaestlea and Ristella are almost exclusive to the Western Ghats mountain ranges and the Indian Subdoluseps are found in drier regions of the Western Ghats and the Southern Eastern Ghats mountains. These hill ranges have ancient origins and are highly biodiverse and might hold an unprecedented diversity within the aforementioned genera of skinks. Since all the species in these three genera are montane-sub-montane species, they might also exhibit a ‘sky-island’ radiation. I intend to explore that aspect as well. 

Apart from looking at lizards, I like to take photographs of animals, read books, watch movies, play some sport,s and have a nice time with my friends. But mostly I just look for critters.

Bikash Sahoo

I joined the lab in July 2019. I am interested in understanding the evolutionary history of Army ant and, I am working on Phylogeny and biogeography of Army ant genus Aenictus Shuckard, 1840 (Hymenoptera: Formicidae: Dorylinae). Army ants are unique in having a set of behaviors known as “Army ant Syndrome”. This includes nomadism, obligate collective foraging, and a highly specialized permanently wingless queen. Army ants are broadly classified as Old World army ants and New World army ants. Genus Aenictus is one of the Old World Army ants.

My work aims at conducting phylogenetic analyses of this genus across their distributional range (Old World tropics) to understand how these species are related to each other. Additionally, I intend to explore the estimation of divergence times and ancestral range evolution to understand how and when these species dispersed to different landmasses, despite their poor dispersal ability.

Besides my lab works, I love to do paintings and going outside to see the amazing World of these tiny little ants.

Pranoy Kishore Borah


I was interested in reptiles in general from a very young age. Surely enough, with time I became more and more keenly lured into the field of herpetology and I knew I had to study some of the more fundamental aspects. With the educational background that I have, Biogeography and Phylogenetics are some of the other domains of biology I gradually got interested in. Naturally, combining these into a well-structured study in the frame of research was something I wanted to do for my Ph.D. My focused research interests include Phylogeography, Biogeography, and Herpetological Systematics. Northeast (NE) India is a treasure trove of biodiversity and is in the confluence of two biodiversity hotspots, namely Eastern Himalaya and Indo-Burma. It harbors a natural setup of varied topographical features comprising different hill ranges and a complex network of river systems dissecting a vastly heterogeneous landscape. The region also has a unique admixture of biota across the ranges that contributes to a high degree of local endemism. For my Ph.D., I will be looking at how different hill ranges and drainage basins in Northeast India act as drivers of speciation for squamate lineages known to differ in their dispersal ability. I shall test how topographic complexity may contribute as a biogeographic barrier for taxa differing in their habitat preference, distribution, and dispersal ability. I shall test this by taking select lineages of squamates from the region that fall within two extremes of the dispersal ability spectrum based on their natural history.

Project Fellows

Madhura Agashe

My childhood adventures mostly revolved around chasing lizards and searching for snakes in the thickets. This interest in “creepy crawlies” was magnified further through formal education in biodiversity, motivating me to convert a mere passion into a research career. I am especially intrigued by the evolution and distribution patterns of reptiles across the Indian subcontinent, and would also like to study their disease ecology.
As a research fellow at the BioGeoSys lab, I will be working on the phylogeny and systematics of endemic skinks from the Western Ghats, which is a biodiversity hotspot.
Apart from going on nature trails to observe the plethora of diversity around us, I like to fill my time with exploring new places and reading books.

Int. MSc Students

Ayush Parag

I took a liking to arthropods in my early college days, and have been intrigued by them ever since. Mostly unnoticed, these multi-legged critters are excellent model systems. I joined the lab in November 2020, assisting Himesh in his master’s work, which involved mites and their beloved hosts, geckos. Presently I am working on spiders, aiming to document the spider fauna of our campus and to work on anything interesting that comes my way! Thanks to Roy, I have been exposed to the mystical world of these eight-legged creatures, which remains poorly understood to date. In the years ahead, I hope to learn more about arthropods and work on finer topics such as their phylogeny, evolutionary and behavioral patterns, and biogeography, similar to the works of my senior labmates.

Ashlesh Pattnaik

The sounds of nature have always been a feast for the ears. But it needs a great deal of observation to understand and unravel the hidden message of these euphonious sounds. Insects and their vast diversity of calls have been one of my primary interests, and I have finally begun a systematic approach in that direction, under Dr. Aniruddha Datta-Roy. Orthopterans are one of the best and most studied model systems to understand the acoustic behavior in the animal kingdom. The preliminary part of my project involves studying the species richness of the Orthopterans in the NISER campus, as well as recording the various behaviors they exhibit. I will be using these observations along with replication experiments in the lab, to answer different questions about mate interaction and prey-predator relations with respect to their acoustic cues. I will also try to make a comparative analysis of the behavior of species found here and their closely-related species on which some research has been done. My project here will hopefully give me an insight into the acoustic behavior of insects, which will help me extend my work to other animals in the future.

Karunakar Majhi

Life on earth is remarkably diversified. The differences between each species serve as significant evidence for differentiating them on the basis of reproductive isolation, morphology or even genetic structure, this often becomes more and more complex with the idea of what actually defines itself as a species. Species delimitation is the process of determining which species constitute different populations of the same species and which constitute different species altogether. I am a master’s student under the guidance of Dr. Aniruddha Datta Roy. I am interested in phylogenetics, biogeography, and behavioral ecology. I am currently working on the species delimitation of various described taxa such as a group of frogs (Genus: Raorchestes). In my project, I will re-evaluate the genetic sequences of the related taxa and run them through different species delimitation tools and try to estimate and validate the number of species in that particular group. In my free time, I love to write works of fiction and watch films. 

Ansuman Satyaswarup

Reptiles are fascinating creatures seen almost everywhere starting from inside our houses. There have been many studies regarding their diurnal activities, but their sleeping behavior remains the least studied, and has mostly been limited to laboratory studies. I am interested in studying the sleep ecology of the oriental garden lizards (Calotes versicolor) in the wild. They are arboreal organisms of the family Agamidae. I am focused on studying their sleeping habits such as perch selection, sleeping posture and orientation under artificial light and in dark, in relation to their age and size. I will be using visual sampling to make observations and some non-invasive techniques to check for their site fidelity. I will also be estimating their population density inside the NISER campus. My hobbies include PC gaming and nature photography.

Former Members

Jagati Vishwa

I’m interested in the ecology of birds. The ecology of birds tells us how they fit into the environment in which they live, and how they coexist with other organisms. I’m working on the breeding ecology of Yellow-wattled lapwing, Vanellus malabaricus. My work aims at analyzing their nesting patterns, exploring the predators’ activity and their effect on nesting, quantifying the camouflage of the eggs since it is their primary strategy against predators, and relating this camouflage to the hatching success rate. Furthermore, I aspire to know the reason for an earlier onset of breeding activities before their actual breeding season, and also their multi-brooding behavior on the NISER campus.

Alex Mahesh

The beauty of nature and the variety of life forms around us has always fascinated me and I have always wondered how we have such awesome life forms around us. In the lab, I work on ‘ant mimicking’ spiders which are really cool organisms, as sometimes you may think you are looking at an ant unless the spider drops down on the web in front of you. I am trying to find out the evolutionary relationship between these ant-mimicking spiders and the model ants which they mimic. My hobbies include playing all sorts of outdoor games and roaming around without any reason.

Himesh Kumar Behera

There are more than 200 described species of mites parasitizing lizards permanently, and no one knows about their evolutionary interactions. Geckos are my favorite and my master’s work on coevolution between geckos and their ectoparasites tries to uncover some of these mysteries.

Shagun Sabharwal

Scincid genus Sphenomorphus has a very unique distribution in the Indian subcontinent. Sphenomorphus are distributed all over Southeast Asia, but with only 5 species in India. Even in India, 4 species are found in Northeast India and only 1 in Kerala. This unique distribution must have a fascinating history. My project aims to derive the relationship between the species by analyzing their biogeography, timing of speciation, and major historic geographical changes.