Biology concerns itself primarily with understanding the life-mechanisms, diversity, relatedness and adaptedness of life forms, and the processes shaping the spatial and temporal patterns we see in the living world. Evolution, broadly taken, explains the diversity, relatedness and adaptedness of life forms. In this talk, I will develop a view of biology that stresses the dynamics of how population compositions change over time, emphasizing the interplay of three major “phenomena” in biology: development, ecology and heredity. The picture emerging from this view of biology constitutes the framework within which much of the mathematical modeling in both ecology and evolutionary biology is carried out. I will discuss this framework in an attempt to clarify the relationships between the various approaches to modeling the evolutionary process that are taken in evolutionary ecology, population genetics and quantitative genetics.

Darwin included only one figure in the Origin of Species, which depicted an “evolutionary tree”. This metaphor of evolutionary change is now being challenged. Instead of a tree like structure, the so called “web of life” metaphor possessing strands interconnected by genetic exchange has been supported by a growing number of data sets. This talk will delve into the evidence supporting the new metaphor, with much of the discussion centering on our own species, and those species with which we daily interact.

Claude Alvares is a name that needs no introduction for people who are into conservation or the organic movement. For the rest, a notorious man who has stalled the mining giants from plundering the country's resources for the last 3 decades and successfully so. He has very strong views on our current education system some of which might be hard to digest. He claims to have worked on a meagre salary of Rs 10,000 for the last 3 decades and to make a living he runs Other India Press. He grows his own veggies and is a content man. His 3 kids are home schooled and he can talk at length on the merits of right education. He will be here to share his recent work on Organic Farming and also share the secrets of how to battle giants in order to conserve our forests and such. Depending on the interest of the audience he can sway in any direction so please feel free to ask the questions of your interest.

The ability to fly has enabled insects to evade predators, disperse, and
occupy diverse niches leading to their remarkable success. Most flying
insects have undergone miniaturization. Miniaturization or a reduction in
body size implies reduced wing span which results in reduced aerodynamic
forces. To overcome the reduced lift, flies (order Diptera) flap their
wings at very high frequencies, often exceeding 100Hz. These rapid wing
beats are powered by specialized myogenic muscles. Their fast and exquisite
flight maneuvers are controlled by rapid feedback from halteres; modified
hind wings that have evolved into mechanosensory organs. Halteres also
oscillate at wing beat frequencies but at precise phase relationship to the
wings. The two contralateral wings also oscillate precisely in-phase with
each other. Flies must maintain precise phase coordination between wings
and halteres for stable flight. This coordination occurs at rates that are
often difficult to achieve via active neural control. Our results show that
this rapid and yet coordination of wing and haltere motion is achieved by
passive, mechanical connections within the fly thorax instead of being
under active neural control. Coupled by mechanical linkages, wings and
halteres act as coupled oscillators. This mechanical coupling ensures
robust coordination even if there are slight differences in the natural
frequencies of wings and halteres due to developmental errors or
environmental damage for e.g. in flies with torn wings often seen in the
wild. In addition to the passive, rapid coordination flies use an actively
controlled clutch and gear box under each wing base which allows
independent control of individual wing motion despite being mechanically
connected. Passive mechanical coupling might be a general mechanism that
enables rapid coordination in various miniaturized insects like bees (order
Hymenoptera) and beetles (order Coleoptera).

One of the basic issues in evolutionary biology is to understand the mechanism(s) underlying the formation of new species, new units of diversity and of evolution. The more advanced the stage of speciation of two diverging populations, the more difficult to delineate the genetic/evolutionary events that has set the process in motion. In this regard, studies on Experimental evolution, wherein populations that are maintained for hundreds of generations in laboratory or controlled field manipulations facilitates to witness the evolutionary changes in real time and may throw light on the processes and patterns of events in nature. Introgressed populations resulting from the interracial hybridization between D. nasuta (2n = 8) and D. albomicans (2n = 6) form the material for the present study. The hybrid populations of these races can be maintained for any number of generations and as of now they have crossed over 700 generations in the environs of the laboratory. These hybrid populations are being maintained in different cages and each one of them is called a 'Cytorace' and there are 16 Cytoraces (C1 - C16). Parental races namely D. nasuta and D. albomicans and the newly evolved Cytoraces (C1 - C16) are grouped together and this cluster is named "nasuta-albomicans complex" - a new taxonomic unit. This 'allosympatric' assemblage of closely related forms has become a goldmine for studies on evolutionary cytogenetics. These cytogenetically closely related members are passing through the process of population differentiation reflecting different patterns of divergence for different sets of phenotypes such as karyotypes, neo-sex chromosomes, morhophenotypes, life history traits, mating behaviour with incipient isolation, Repetitive DNA, isozymes, glue proteins, a few gene loci such as sod1, Rpd3, Aly, and Rab etc. The members of this complex which are at different stages of divergence offer a rare and an unique opportunity to look into multidimensional process of raciation. I will summarize the results of these investigations and also of the ongoing studies and wish to share the pleasure and excitement we experienced during the course of this study.

Most distribution patterns in nature have been shaped by contemporaneous ecological processes as well as historical events. From a historical perspective, availability of dispersal routes and biotic interactions in evolutionary time as well as paleoclimate and geology have contributed to current distributions. In this regard, the Indian subcontinent provides us with an interesting setting to address questions in biogeography and phylogeography. This is because the Indian subcontinent has experienced diverse geological and climatic changes ever since it separated from Gondwanaland supercontinent. Given this background, one of the fundamental questions in Indian biogeography is, how, when and from where different groups colonized India.Furthermore how have these historical events contributed towards diversification within India.One of the approaches to understand the contribution of historical processes in shaping distributions is to study a system at multiple taxonomic levels.
I plan to address these question using freshwater snails as a model system. Freshwater snail families -Ampullariidae and Viviparidae have contrasting global distribution, suggesting different routes and time of colonization of India. This makes them an ideal system to test different hypothesis regarding their evolutionary origin. Additionally given their habitat preference and modes of dispersal, understanding genetic patterns within a species will be also an exciting area of enquiry. Bellamya bengalensis, a widespread species, is the ideal system to study such patterns in peninsular India. Hence, both biogeographic and phylogeographic studies will be implemented to understand diversity at various spatial and evolutionary scales.

Phoresy is an interspecific and temporary relationship in which the phoretic organism (traveller) actively seeks out its vehicle (carrier) for dispersal out of unsuitable areas for further development of itself or its progeny. In nature, this unsuitability of areas might arise due to over-crowding, habitat deterioration, sibling rivalry or unavailability of mates. These conditions generally lead to the development of a close association between the traveller and the host and the traveller might therefore also show synchrony with the host life cycle. The traveller not only needs to locate and latch on to its carrier but also should not have a greatly detrimental effect on the host which would prevent it from being transferred to a new favorable environment. Only few studies in phoresy have indicated that the carrier might bear the cost of such a relationship but this cost has not been adequately quantified. The addition of a third interactant leads to the development of a tritrophic interaction which increases the complexity of the system and might require an increase in the traveller’s specificity towards the carrier. One system in which nematodes show a highly species-specific tritrophic phoretic interaction is the well known mutualistic fig–fig wasp system.

In fig–fig wasp–nematode system, the fig nematode is the traveller, the female pollinator wasp serves as the vehicle and the fig is the substratum for their development. The pollinator wasp is the most reliable carrier as non-pollinator wasps that also occur within this system do not enter syconia in most fig species; the male fig wasps, being wingless, do not fly at all and die within their natal syconium. Such a phoretic system requires great specificity between nematodes and female pollinator wasps. Therefore, this system gives us an excellent opportunity to investigate the cost of phoresy on the mutualism between the fig and the fig wasp and the mechanism of dispersal of these phoretic organisms between figs.

Animal communication involves a transfer of information from signaller to receiver through different sensory channels. Effective communication between conspecifics can sometimes require the use of two or more sensory channels, making the communication multimodal. I am interested in understanding the phylogenetic patterns and ecological drivers of multimodal signalling. My study broadly revolves around three aspects of animal communication and signalling: morphology, behaviour, and environment. As a model system, I plan to use seven species of the day gecko, Cnemaspis, all of whom have male-specific throat-colour and femoral gland secretions that are likely used in social and sexual signalling.
My main objectives are to: Compare the signalling morphology of multiple species of Cnemaspis and determine whether there is a trade-off between visual and chemical signals; Quantify behavioural responses of male and female conspecifics to each visual and chemical signal separately and simultaneously and determine the relative importance of the two signals in multimodal communication; and Understand how current microhabitat conditions affect the morphology and behaviour associated with multimodal signalling in multiple species of Cnemaspis.

The communication system in the order Orthoptera (crickets, katydids, grasshoppers) consists of stationary males broadcasting species-specific acoustic signals which are used by females in conspecific recognition and localisation. Some species show deviation from this behaviour, engaging in duetting, with females also contributing to the signal repertoire and the males actively contributing to localisation. A unique duetting system was recently discovered in a katydid species Onomarchus uninotatus, where the females reply to a male’s call with vibratory signals and the male localises females using the vibrations. Laboratory experiments establish vibratory signals to be an immediate response to male calls even at the threshold of female hearing. This presents a paradox as the species is a canopy insect which limits the range of communication through vibratory signals. This is the first known case of female tremulation in response to the male acoustic call being used as a long-range signal. I plan to investigate the functioning of this multimodal duetting in the wild and the factors that could have led to the evolution of such a communication system.

The evolution of extreme form of altruism in the form of forsaking reproduction in order to help others to reproduce is arguably one of the most interesting paradoxes in biology. One of the theoretical frameworks that allows one to understand the evolution and maintenance of such behaviour is W D Hamilton's kin selection theory. *Ropalidia marginata*, a species of wasp in which generally only a single female lays all the eggs at a time, though most of the females are capable of developing their ovaries and laying eggs, is an excellent system to study the implications of this theory. One of the parameters in this framework is genetic relatedness. In my work I have estimated this parameter in the initial colony founding stage as well as in mature colonies. I have also constructed several models based on this framework in order to predict the next queen, and tested them. In addition I have studied the genetic structure of *R. marginata* populations. I found nestmate relatedness to be lower than the expected 0.75, with newly founded colonies having even lower average relatedness than mature ones. The queen's successor could not be predicted form any of the models. Regarding its population, *R. marginata* had quite high level of structuring and absence of any inbreeding. Moreover, structuring was higher at the level of the colonies.