Movement in organisms is driven by multiple factors, foremost among them the need to acquire resources in spatially structured environments where resources are unevenly distributed. However, ecological communities are defined by the ubiquity of species interactions—ranging from competition and predation to mutualisms—which fundamentally shape the decision to move and thereby influence the evolution of motility. In species engaged in cross-feeding mutualisms (CFMs), where partners exchange benefits via the environment, the adaptive value of motility becomes especially complex. While motility can enhance resource acquisition, it also carries the risk of displacing individuals away from their mutualistic partners—regions typically rich in resources—and imposes metabolic costs associated with flagellar construction. Using a spatially explicit, mechanistic model of mutualism, we demonstrate that selection for or against motility depends on: 1) the motility status of the partner, 2) the production and uptake rates of cross-fed resources, and 3) the magnitude of motility-associated costs. We further test our simulation outcomes with experimental data from a microbial CFM involving Escherichia coli and Salmonella enterica. Our results reveal that while motility is consistently favored in S. enterica irrespective of E. coli’s motility, the selective pressure on motility in E. coli is contingent upon whether its partner is motile. This study underscores how the pervasive nature of species interactions in ecological communities plays a crucial role in shaping the evolution of bacterial motility.

This lecture will cover the foundational elements of eco-evolutionary dynamics, providing an overview of the key components involved in modelling population and evolutionary processes. It will introduce core concepts related to quantitative phenotypic traits and explore how these traits link to population and community dynamics. The lecture will also discuss essential principles of quantitative genetics, the assumptions underlying these models, and how evolutionary dynamics emerge and feedback to influence population dynamics. Serving as an introduction, this lecture will act as a basic guide that will go through the steps required to develop a simple eco-evolutionary dynamical model.

Individual trait variation is ubiquitous in nature and is central to populations involved in complex interactions with others in an ecological system. Such variation drives eco-evolutionary dynamics, shaping how populations and communities respond to environmental perturbation. In this talk, I will provide an overview of how individual variation can scale up to influence the stability, predictability, and resilience of populations to environmental perturbation, as well as the recovery dynamics of collapsed ecological communities. Furthermore, I will explore how individual trait variation, which is critical to species interactions within complex ecological networks, can dynamically evolve in response to changes in interaction strength, environmental perturbation, and network architecture. This consequently impacts how complex communities respond to changes in the environment. Lastly, the talk will highlight the importance of incorporating the adaptive nature of species interactions such as rewiring, eco-evolutionary feedbacks, and dynamic resilience frameworks to better understand the responses of complex communities to environmental change.

The research questions explored by Earth scientists, though they may not initially seem directly relevant to ecological research, can ultimately yield valuable insights for the field of ecology. In this presentation, I will illustrate this with two examples. First, our investigation into the sulfur isotopic composition of rocks, and later bird feathers, not only provided insights into bird migration patterns but also helped identify the sulfur source in the part of the food chain. In this section, I will present the results of sulfur isotopic variability in the feathers of both resident and migratory birds in India. The latter part of the talk will focus on the biogeography of tree structures at the landscape scale in the Western Ghats. This research challenges the assumption that asymmetric heating—often responsible for vegetation distribution in mid-latitudes—does not apply in the Western Ghats due to its lower latitudinal position. The study emphasizes the significant role of the monsoonal climate and asymmetric solar heating in shaping tree structure in the region

Soil microorganisms are the unseen majority in soil, that drive critical ecosystem processes, such as biogeochemical cycling of nutrients. For growth and metabolism, microbes require nutrients, which are either readily available as simple compounds or locked within complex macromolecules. To access these nutrients, microbes secrete extracellular enzymes into the soil matrix. This study focuses on three widely studied enzymes: β-glucosidase (BG, carbon-acquiring), N-acetyl-β-Glucosaminidase (NAG, nitrogen-acquiring), and phosphatase (AP, phosphorus-acquiring). Soil enzyme activity exhibits substantial spatial heterogeneity. To investigate the abiotic factors regulating enzyme activity at larger spatial scales, I compiled data from 54 published studies reporting enzyme activity in natural soils. I examined the effects of biome, edaphic factors (pH, organic carbon [SOC], total nitrogen [TN], total phosphorus [TP]), climatic factors (mean annual temperature [MAT], mean annual precipitation [MAP]), and geographic factors (elevation). Our results revealed that N-acquiring enzymes showed no significant differences across biomes, suggesting widespread nitrogen limitation. Conversely, C- and P-acquiring enzymes exhibited the lowest activity in desert soils, likely due to moisture limitations.

C acquiring enzyme activity was negatively affected by MAP, suggesting reduced carbon acquisition in wetter conditions, while SOC had a positive influence. NAG activity also decreased with increasing MAP but was positively influenced by elevation and TN, indicating enhanced nitrogen acquisition at higher elevations and with greater nitrogen concentrations in soil. For P acquiring enzyme, elevation and soil pH had negative effects, with reduced phosphorus acquisition at higher elevations and in more alkaline soils, whereas SOC positively influenced P acquiring enzyme activity. This study highlights the complex interplay of biotic and abiotic factors regulating soil enzyme activity across spatial gradients. Further research could explore additional factors or interactions to refine our understanding of microbial contributions to nutrient cycling.

This lecture explores the innovative use of Lab-on-a-Chip (LOC) technologies in conservation and environmental applications. LOC devices, which miniaturize laboratory processes onto a single chip, offer rapid, cost-effective, and portable solutions for monitoring ecosystems, and conserving biodiversity. The presentation will cover the integration of microfluidics, sensors, and bioanalysis for real-time environmental data collection, highlighting their potential in addressing global challenges. Case studies demonstrating the impact of LOC in wildlife conservation, and ecosystem monitoring will also be discussed.

Multiple traits, including antipredator responses, foraging behaviour, development rate and fecundity, contribute towards an organism's fitness. These diverse traits interact through the shared resources allocated to maximise fitness. Ecological conditions can affect these interactions by driving increased investment in a particular trait at the cost of other traits (inter-trait trade-off). How are these interactions affected when an individual goes through different development stages, which serve different functional roles? What are the consequences for an individual's fitness in such a complex life-cycle?
To understand the trade-offs that operate at multiple levels in a complex life cycle, I investigated the role of early predation risk conditions across the life cycle of the holometabolous insect– Aedes aegypti. Aedes aegypti has four major stages: egg, larva, pupa, and adult. Previous work suggests that ecological conditions experienced by the larval stage affect adult traits. However, we lack knowledge of how early larval conditions affect the pupal stage and the cumulative effects of both stages on adult traits.
To understand multistage, inter-trait trade-offs, I exposed the immature stages to a key selection pressure, predation risk. Leading to our aim of understanding the combined and individual roles of larval and pupal stages in managing trade-offs, I first unravelled the relationship between larval and pupal stages. I adopted behavioural approaches to examine (1) the carryover of larval predation-risk experience on the pupal stage to understand if a pupa independently responds to risk or whether the larval experience influences its response to risk conditions. I discovered that a pupa that has experienced predation risk as a larva modulates its response to predation cues, showing that the larval experience affects pupal traits. This experiment showed that a behaviour or experience with an adaptive value can overcome the barrier of metamorphosis. Since Aedes aegypti larvae and pupae are found in group settings, I also examined (2) the behavioural manifestation of predation experience in a group setting. This allowed me to understand the abilities of the pupal stage in responding to risk conditions under different contexts. I found that experience does not influence the behaviour of an individual pupa if it is in a group. This is probably because being in a group is an antipredator response itself. My first two chapters highlight the need to include the pupal stages in life history studies because of their ability to process different cues while responding to their environment.
After discovering the context-dependent antipredator response of the pupal stage, I examined (3) the multistage trade-offs, driven by early predation risk conditions, between larval-adult, pupal-adult and larval-pupal-adult stages. I performed lab-based controlled experiments where I followed all the life stages under risk and no-risk conditions. On analysing diverse morphological, biochemical and life-history traits of risk-experienced and naive individuals, I demonstrated that the fitness consequences differ for males and females, and it may start from larval-pupal trade-offs and accumulate as the risk persists. I also found that the pupal stage, like the larval stage, can respond to risk conditions both behaviourally and physiologically. However, it is less well-equipped than the larval stage to manage the trade-offs. Fitness consequences are worse when the pupal stage alone experiences risk. Hence, different stages can contribute to trade-offs that lead to various fitness consequences.
My thesis yields novel insights into life history evolution by displaying the ability of individual life stages to manage trade-offs. It highlights the importance of a poorly understood pupal stage, which can respond to different environmental cues, behaviourally and physiologically. It also explains how the abilities of individual stages to manage trade-offs independently and cumulatively can change the consequences for adult fitness.

Invasive alien species represent a significant global threat to ecosystems, economies, food security, and human health. They are responsible for 60% of global plant and animal extinctions. In 2019, the global economic cost of invasive species exceeded USD 423 billion annually, with costs increasing at least fourfold every decade since 1970. High-elevation ecosystems, however, remain among the few areas not yet heavily impacted by these species. This is expected to change as invasive species expand their range upwards to occupy new climatic niches in response to ongoing human-induced disturbances. The construction of infrastructure, such as roads and railways, is accelerating this process, particularly in the Kashmir Himalaya. Particularly, the roads act as effective corridors, facilitating the spread of invasive species along elevation gradients in mountain areas. In my presentation, I will discuss what we know about plant invasions in mountainous landscapes in general, with a particular focus on the Kashmir Himalaya.

My research explores the dynamic and multiscale nature of animal behavior, integrating insights across scales of biological organization. Today, I will discuss two key directions of my work.

Firstly, I will present past findings about how the brain makes decisions when faced with spatial choices. I will highlight the evolutionary universality of this algorithm and discuss the consequences this has for our understanding of movement and social influence in animal collectives. I will emphasize why explicit consideration of space is important for decision-making processes and extend these insights to ecologically and evolutionarily relevant contexts, specifically to the study of mate-choice on antelope leks.

Secondly, I will delve into a new research direction focusing on animal search behaviours, using prey search in octopus-fish hunting groups as a prime example. Contrary to traditional views, my field-based analysis reveals mutual benefits in these mixed-species relationships, with different species contributing to group movement decisions in distinct ways. By leveraging natural variations in group composition, I demonstrate measurable improvements in octopus foraging success within these mixed-species hunting groups.

Overall, my research underscores the importance of integrating insights across biological scales for a comprehensive understanding of animal behaviour and its ecological implications.

Social insects like ants, bees and wasps are well-studied for their efficient colony organization through division of labor, and their complex mode of communication, primarily mediated through chemical cues. Although the first social insect genome was sequenced nearly 20 years ago, it is only in recent years that neurogenetic tools have been developed to study the molecular and neural pathways underlying social behavior. I will use two social insect species- a tropical paper wasp and an army ant - to illustrate how the integration of behavior, genomics, and neuroscience can provide a holistic understanding of behavioral phenotypes and uncover novel mechanisms driving social behavior.