Collective behaviour is a commonly observed phenomena which
encompasses a wide range of organisms – from swarming microbes to insects
to aggregation of whales. These groups which from through individual level
interactions exhibit interesting features like shifting from one form of
organization (for example a swarm) to the another (highly polarized). These
shifts are analogous to phase transitions in physical systems, and have
implications in ecology.

Phase transitions (shifts from one state to another) have been studied to a
great deal in physics and various fields of ecology, from lakes to corals
to semi-arid ecosystems. Scientists have developed statistical methods to
recognize and anticipate such shifts. Here we employ some of these methods
to check whether these generic statistical indicators of transitions which
sense shifts between ecological states, also capture signals in behavioural
transitions from one type of collective movement to another (e.g. swarm to
polarised group motion).

We discuss some possible biological motivations to investigate indicators
of transitions. Mass migration of animals is a process where some abiotic
factor (decrease in resources, change in climatic conditions, et cetera)
causes sedentary organisms to disperse to other parts of the world. This
process involves the movement of multiple individuals from a certain point
in space to another and also shift in the form of organization of migrating
animal societies (less polarized/random movement direction of individuals
in swarms to highly coordinated individual movement in groups).

Motivated by the above considerations, here, we simulate a simple agent
based model of the collective movement which generates a number of
biologically realistic grouping patterns through very simple local
interaction rules. We generate time series data of the group alignment by
varying the key local interaction parameters. We then generate a phase
diagram which shows how the state of the collective motion changes across
the key parameter value which we changed. Then, we use the time series data
which exhibit collective behaviour movement transitions to check for
distinct changes in the values of the statistical indicators. Based on the
change in the value of the indicator parameters prior to the shift in the
organizational pattern, we claim whether using these tools we can sense
imminent transitions or not in the time series data.

The time series that we had generated and used for the analysis, have shown
mixed results. We find changes in the values of the statistical measures
prior to the shift in states which inform us about the transition before
its onset. There were also scenarios where we obtained peculiar and also,
failed signals. Hence, these tools have some importance in their ability to
capture systemic changes prior to transitions in the states of collective
motion of animals but they are also not predictive of such events. Our
study suggests that it is worthwhile to test if these signals show similar
or some characteristic patterns before transitions in real animal group
movement data.

The terrestrial biogeochemical processes are perhaps the most dynamic and complex
component of the Earth’s Climate system. In order to better understand this complex system, the
integrated use of process-based modeling, remote sensing (RS) and measurements at multiple scales
(with an ecohydrological spirit) is proposed.
At the outset, a process-based ecohydrological model (BEPS-TerrainLab V2.0) that has tight
coupling of water (W), energy (E), carbon (C) and nitrogen (N) cycles is discussed as applied to a
forested ecosystem in boreal Canada. The potential errors in the simulated C fluxes under abstracted
hydrology are presented using a numerical experiment. Further, an improved and generic model
(STEPS) is presented as applied to a patchy-landscape in southern France. Improvements made
towards the modeling of canopy radiative transfer mechanism, in addition to some issues that are
pertinent to agro-ecosystems (C4 photosynthesis, irrigation, fertilizer N etc.) are presented. In the
second part of the presentation, long-term modeling of C in the soil and vegetation is discussed from
the lessons learnt from various projects in the Canadian C Program and the AmeriFlux programs.
Some studies on the long term ecohydrological responses under climate change in the lower
Himalayas are also discussed.
Finally, large-scale ecohydrological interactions are discussed. An analysis of the recent trends
in the global vegetation is explored using long-term RS data (AVHRR). Because of the importance of
soil water in governing the global vegetation, I hypothesize a major limitation in the widely used
global estimate of terrestrial photosynthesis (MOD17A2). A modeling strategy that is being developed
to improve the MOD17A2 by incorporating soil moisture data is briefly explained. In this regard, I
also present an analysis of some global soil moisture products obtained from microwave RS (SMOSL3
and AMSRE-LPRM) with respect to a reanalysis product (ECMWF).

The 90 My-old obligate and mutualistic fig–pollinator wasp system is exploited by parasitic non-pollinating fig wasps that are fig-species specific and oviposit into their hosts from the exterior of the fig which serves as a wasp nursery. Using Ficus racemosa as the study system, we investigated the underlying mechanisms employed by parasitic wasps to locate hidden hosts, where only cues from the exterior surface or from the interior of the fig could guide this search. We also determined the preference of different parasitic wasps for oviposition sites and hosts within the fig. We show, for the first time, that the fig wasp ovipositor is an olfactory sensor that responds to host volatiles and gaseous CO2. This sensor could be used by the parasitic wasps to evaluate ecologically relevant cues for oviposition. Chemical footprints left by previously ovipositing wasps also influenced oviposition choice. We found that physiological factors such as ageing and egg load greatly influenced oviposition behavior. These findings reveal the different ways in which parasitic wasps exploit their hosts but also have bearing on the survival of a plant–pollinator mutualism in such a complex and multiply-parasitized system.

Speakers

Prof. William Brown, SUNY Fredonia, USA 3-3:50 p.m. (including discussion)
Diptarup Nandi, CES 4:10-4:35 p.m. (including discussion)
Manvi Sharma, CES 4:35-5 p.m (including discussion)

Talk 1: The behavioral ecology of sexual cannibalism in praying mantids
William D. Brown, Department of Biology, State University of New York at
Fredonia
I will present work that my students and I have doing on sexual
cannibalism in the praying mantid Tenodera sinensis. Sexual cannibalism in
most predatory arthropods occurs when the female kills and consumes the
male before, during, or after copulation. The act obviously has strong
potential for generating sexual conflict but evolutionary models suggest
that degree of conflict over cannibalism will depend on the expected
mating frequency of males and additional offspring produced from the
resources obtain by cannibalism. Thus males are predicted to alter their
risk-taking during approach of females depending on perception of mate
availability and the fecundity benefits of cannibalism. I will present the
results of a series of experiments in which we examine the effect of (1)
level of predatory risk, (2) frequency of mating opportunities for males,
and (3) use of male soma for offspring production by females. I will also
discuss our current work assessing mating opportunities in the field, and
our future plans to measure natural mating frequencies and patterns of
paternity to more accurately assess the costs and benefits of falling prey
to a mate.

Talk 2
A sensory ecological perspective on mate sampling strategies: Models and
an empirical test
Speaker: Diptarup Nandi, CES
Abstract
Mating behaviour in animals often involves communication, wherein signals
are produced by individuals of one sex to attract members of the opposite
sex from a distance. Long-range communication signals thus play a central
role in mate search and mate choice in such systems. Among the different
aspects of mate choice, mate sampling has been less explored despite its
significance. Though analytical models of mate sampling have demonstrated
significant differences in individual fitness returns for different
sampling strategies, these models have rarely incorporated relevant
information on the ecology of signalers and sensory physiology of
receivers, both of which can profoundly influence the optimal performance
of a sampling strategy. In this study, we used simulation models to
compare the costs and benefits of different female mate sampling
strategies in an acoustically communicating field cricket (Plebeiogryllus
guttiventris), by incorporating information on relative spacing of callers
in natural choruses, their signal intensity and the effect of signal
intensity on female phonotaxis behaviour. The optimal strategy that
emerged reflected the physiological mechanisms of sound signal
localization (“passive attraction”) rather than active sampling. When
tested empirically in the field, female behaviour was also consistent with
the optimal strategy predicted.

Talk 3
Title: Oviposition site selection response to larval predation risk in
Aedes aegypti
Speaker: Manvi Sharma
Abstract
Animals ovipositing in discrete aquatic patches avoid patches with high
predation risk on their offspring. In nature, magnitude of larval
predation risk varies across patches yet this risk has mostly been studied
at one level of magnitude. We tested how a females of a mosquito species
Aedes aegypti assess a gradient in larval predation risk across
oviposition sites. To understand underlying trade-offs associated with
patch-selection decisions, we quantified consequences of possible patch
selection decisions by measuring larval survivorship across a predation
risk gradient. We find larval survivorship reduced drastically with
increasing predator density. Surprisingly, adult females did not reject
predator pools altogether, but reduced oviposition in “unfavourable”
pools. We suggest that larval predators may provide a release from intense
larval competition and that the interplay between larval predation and
competition may influence the nature of female-avoidance response to
larval predator densities. We also suggest that females make oviposition
decisions at pool network scale.

The film is about multi modal communication found among some rare &
endemic species of frogs found in “Western ghats”, India.
From time immemorial the graceful courtship behaviour of a peafowl has
inspired reams of poetic verses, some one with a sweet voice is always
compared to Indian Koel (a song bird) or perhaps the royal bengal tiger
represents everything that is majestic!
In this film the call of a frog is modelled in to syllables (known as
konnakol) used in the percussion instruments of Indian classical music.
That makes frogs as percussionists!
Equally fascinating is another weird behaviour - foot flagging found among
a certain species of frogs commonly known as dancing frogs. The film
throws some new light on to this behaviour buttressed by solid research.
The behaviour is similar to foot stomping among Sumo wrestlers.
Through “Wrestlers of western ghats”, the producer intends to encourage
the audience to develop fresh perspectives about the wonderful natural
world of which we are an inseparable part. The film is expected to fire up
the imagination of viewers - scientists and general audience alike.

All are cordially invited to watch the documentary and we will be having a
discussion session right after the movie screening.

The 19–49 My-old obligate mutualism between Macrotermitinae termites and the Termitomyces fungus is an example of an ancient agriculture system in which Termitomyces is cultivated by termites for nutrition. Termites, in turn, keep other parasitic fungi like the parasitic weed Pseudoxylaria at bay. Unraveling the proximate mechanisms used in fungal cultivar protection is central to understanding the evolutionary stability of these farming mutualisms. We investigated the role of abiotic factors, antifungal chemicals and hygienic behaviours used by termites to keep their fungal gardens free from such parasitic fungi. Our results show the important role of abiotic factors such as termite mound temperature and CO2 in decreasing parasitic fungus growth. Using novel assays we also found that termites can display a differential behavioural response towards mutualistic and parasitic fungi and that this behaviour is coupled with antifungal activity. These results not only shed new light on how the ecology of these fungi is affected by their host but also reveal the mechanistic basis that may contribute fundamentally to the evolutionary stability of this ancient mutualism.

I use island systems to study ecology and evolution of birds in natural landscapes. Mountaintop habitats, such as on sky islands in different parts of the world, also form islands for species adapted to these specific habitats. It is imaginable that on these sky islands, valleys interrupt species distributions and can lead to range fragmentation, differentiation, and ultimately speciation on an evolutionary time scale. However, there can often be a disconnect between processes at an evolutionary time compared to the contemporary. Many tropical habitats have faced high levels of anthropogenic deforestation resulting in habitat loss and fragmentation. Processes operating at this recent ecological timescale may lead to changes in gene flow patterns and bird song dialects as possible precursors to speciation.

There are very few systems that allow us to investigate both evolutionary and contemporary processes simultaneously. The Western Ghats Shola Sky Islands are one such system where deep, wide valleys (such as Palghat Gap) are known to cause genetic differentiation in varied taxa, while at a smaller scale almost 80% of the mountaintop landscape has been modified by humans.
This system allows us to ask if species adapted to such evolutionary patchiness are impacted by recent anthropogenic patchiness; and what the drivers of these different processes may be.
Across the larger landscape of the Western Ghats, I found a nested impact with the depth and width of valleys impacting species differently, possibly due to the interaction of topography and paleoclimate. This study led to the description of two new genera of birds, with endemic radiations of seven species.
At a localised spatial scale, population genetic data of one endemic passerine across the landscape revealed higher contemporary differentiation relative to historic differentiation in anthropogenic fragments, despite the species’ ability to historically traverse shallow valleys. Simulations confirm recent isolation in the anthropogenic fragments of Western Ghats. These fragments are thus akin to islands within natural islands of montane habitat.
Birdsong, analogous to human language, is a cultural trait that changes rapidly and can be transmitted horizontally, across generations. In some passerine species, songs could thus provide greater resolution of isolation. Analysis of song data at a similar scale (to genetic data) reveals that songs have also changed rapidly in this system. Changes in spectral traits appear to correlate with recent anthropogenic isolation while syntax changes correlate with historic isolation.
I plan to conduct further research, hoping to expand to other landscapes, examining underlying causes for the emergent patterns that I have discovered in this landscape.

Organised by Dr. Praveen Karanth Lab

This is a six day intensive course, which would entail lectures on phylogeny, biogeography, ecology and behaviour using herpetofaunal model systems. Selected applicants from across the country can also attend lab sessions dealing with hands-on training in taxonomy of reptiles & amphibians as well as basics of phylogenetic tree building using molecular data. The outdoor sessions include field techniques and basic photography.

The workshop starts at 9 AM on November 1st and goes on till 6:30 PM each day, till November 6th.

Venomous animals have fascinated humans for millennia, and for good reasons. Injection of even miniscule amounts of certain venom components can result in rapid paralysis and death. The evolution of venom, one of nature’s most complex biochemical concoctions, has underpinned the predatory success and diversification of numerous animal lineages. Such a cocktail of pharmacologically active peptides, proteins, salts, and organic molecules is often employed for both predation and defence by the secreting animal. I study animal venoms as a model system to understand various aspects in evolutionary biology, molecular biology and ecology. I have studied venoms across the breadth of the animal kingdom, including those of snakes, lizards, cnidarians (jellyfish, sea anemone, corals and hydras) – the first venomous animals, scorpions, spiders, centipedes, insects, vampire bats and coleoids (octopus, cuttlefish and squids). I employ an interdisciplinary approach, spanning omics (transcriptomics, proteomics and genomics), bioinformatics (e.g., simulations, evolutionary rate estimations, sequence and phylogenetic reconstructions) and molecular biology (e.g., transgenesis) in order to uncover i) the molecular and biochemical diversity in animal venoms; ii) the evolutionary origin and diversification of toxic protein families and the toxin- delivery apparatus; iii) the role of environmental and ecological factors in driving the evolution of venom and the venomous animals; iv) the molecular mechanisms of causing toxicity; and v) the evolution of venom resistance in prey animals. Most importantly, my research aims at utilizing the aforementioned information for the production of highly specific, efficient and cost effective next-generation antivenoms in India, where snakebite has become a socio-economical disease.

Existence of geographical clines have equally attracted ecologists and evolutionary
biologists. In recent years our understanding of geographical clines has immensely improved.
The most promising pieces of evidence come from studies showing phenotypic change
observed over seasonal time scales i.e. temporal variation. Temporal variation in selection
pressures could be at least partially responsible for the generation of latitudinal clines that
appear so pervasive in Drosophila melanogaster. However, the connection between temporal
and spatial evolutionary dynamics of life histories remain to be comprehensively tested in
nature. Increasing recognition that evolutionary processes can operate on ecological time
scales has generated growing interest in eco-evolutionary dynamics, where evolutionary
change alters ecological interactions, which in turn, feed-back to alter subsequent
evolutionary change. Much of the interest in this process stems from the hypothesized ability
of reciprocal feedbacks between ecology and evolution to influence how populations respond
to environmental change. Nonetheless, our understanding of this important relationship is in
its infancy. Progress is hindered by the difficulty of manipulating rapid evolution in field
populations, limited molecular resources to understand adaptation, and the inherent difficulty
of quantifying how the effects of evolution on ecological dynamics feed-back to affect
subsequent evolutionary change. My recent research work uses orchard populations of D.
melanogaster as a model system to understand how eco-evolutionary dynamics influence
adaptation to a seasonally changing environment. The work explores the population dynamic
consequences of manipulating fly evolution in tree-scale field mesocosms with an innovative
offspring replacement methodology. Parallel experimental manipulations quantify the
importance of temperature and density as drivers of rapid evolution. Utilizing the strengths
of D. melanogaster, the phenotypes, and genomic regions that underlie the adaptive response
to these and other seasonally changing factors are identified and evaluated for functional
significance