The unique geological history of the Indian Plate and its current position at the junction of biogeographic realms make it a fascinating landscape for biogeographers. Geckos are a useful model system for studies in historical biogeography because of their diversity and antiquity. The bent-toed geckos in India include the Palaearctic naked-toed geckos ('Cyrtopodion'), Cyrtodactylus and Geckoella. Each of these have unique distributions, the arid-adapted Palaearctic naked-toed geckos are at the southeastern limit of their global distribution, Cyrtodactylus at the northwestern limit, and Geckoella is endemic to Peninsular India and Sri Lanka. I sampled for bent-toed geckos across India and placed each group in a dated global phylogeny to understand how each group diversified, gaining insights into the biological history of the Indian subcontinent from gecko biogeography. The first chapter deals with the Palaearctic naked-toed geckos and Hemidactylus. Palaearctic naked-toed geckos track the aridification of NW Peninsular India, with middle Miocene dispersal into India and late Miocene diversification while data from Hemidactylus suggests Peninsular India had also begun drying by the early Miocene. The second chapter deals with Cyrtodactylus, the most speciose lizard genus in the Himalayan region. Cyrtodactylus diversification in the Himalayas and Indo-Burma closely tracks geological events related to India-Asia collision, with a number of geographically concordant subclades resolved in Indo-Burma. The third and final paper presents a Geckoella phylogeny and contrasts historical diversification in Geckoella and Peninsular Indian Hemidactylus, which overlap in geographic range and both date to the Oligocene. Geckoella phylogeny reveals deep splits between India and Sri Lanka, and between Indian dry and wet zone species going back to the late Oligocene. Peninsular Indian Hemidactylus and Geckoella show contrasting diversification through time. Geckoella shows signals of niche conservatism and appears to have retained its ancestral forest habitat, and a slowdown in diversification followed by a late Miocene burst in speciation may be linked to historical forest contraction and expansion with global climatic fluctuations. Indian gekkonid diversity is vastly underestimated with sampling revealing 30 potential new species. The Indian dry zone is an overlooked reservoir of biodiversity and field sampling is vital to document basic diversity and distribution. Distinct geographic associations and high diversity make geckos in India an excellent system for historical biogeography.

Cooperation is widespread in the animal kingdom. Studies have sought to explain the evolution of cooperation through kinship, reciprocal interactions, and spatial structures arising from limited dispersal of offspring. However, animals across taxa live in complex dynamic social groups that constantly merge and split. In such cases, these mechanisms cannot be invoked to explain cooperation. Using individual-based simulations, we show how emergent differences in the movement characteristics of cooperators and defectors can lead to the evolution of cooperation without communication, kinship, reciprocity and limited dispersal. I propose an empirical test of our model in a semi-virtual system with real fish predators and virtual simulated prey.

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Two morphologically indistinguishable host races of the fall armyworm have been identifies and we examined the behavioural and chemical ecology of pheromone mediated mating in the two races, as well as in the hybrids, to determine the possible role of both male and female sex pheromones for reproductive isolation.

In this talk, I will focus on how growth rate of ecological knowledge has been limited by statistical issues that we did not deal with well, at least initially. But of course there are recommendations for how we can do better, and, I share some of these ideas with students and practitioners as they embark on answering new questions and/or meeting new challenges.

Understanding species distribution and richness can contribute significantly to our knowledge of community assembly and macroecological patterns, as well as to the effective conservation of threatened species and habitats. Although there have been a plethora of studies on birds in India over the years, there is a critical need to accurately delineate species distributions and understand patterns of richness. The focus of this study was to understand the factors that influence the distribution of bird species in the Western Ghats, as well as to explore patterns in their geographic range sizes. These questions were addressed at the scale of the entire Western Ghats using a combination of primary field data comprising 78 one km transects across habitat types and a published secondary dataset comprising 57 transects. Random forest analysis and species distribution modeling were used to examine the influence of environmental factors, and the relationship of floristics and vegetation structure on bird species distribution were explored using Mantel’s tests. Species distribution models also produced fine scale maps which were used to investigate patterns in range sizes in terms of species-specific traits and compared with currently available information on range. The specific approaches used to address these questions and the findings will be presented at the colloquium.

The history of botanical exchanges between Africa and the Indian
subcontinent reaches back in time over 5000 years. Recent advances in
archaeobotany have revealed these connections through evidence of food
crops of African origin found at various archaeological sites in the
subcontinent. However, little is known about the people that brought the
crops to these places and other parts of the Indian Ocean world. This is
also the case with other plants from Africa such as the charismatic
baobab tree (Adansonia digitata L.) that appears to have had a
longstanding presence in South Asia. Most scholarly accounts assume that
'Arab traders' were responsible for introducing baobabs to this region
but do not offer any reasons for their doing so. Few scholars, if any,
have sought to relate the dispersal of baobabs with the history of
African migrations to the region. This presentation reveals the elusive
traces of their entwined environmental histories by linking baobab
genetics with historical accounts and cultural evidence of the presence
of African diasporic communities in South Asia.