Organisms can cope with novel challenges by modifying their behaviour, physiology,
morphology and cognition. In today’s world, however, anthropogenic activities, such
as urbanisation, rapidly and dramatically change natural environments, altering
habitats as well as shifting resources and predator communities. To understand the
impacts of urbanisation on phenotypic traits, I studied the social and survival
strategies of the Indian rock agama, Psammophilus dorsalis. Using a combination of
field and laboratory-based experiments, I examined differences in gross morphology,
signal-receiver dynamics in communication, anti-predator strategies, stress
physiology, and spatial learning. Social interactions in this species involve rapid
physiological colour changes and behavioural displays. My work shows that colour
patterns are diametrically different between courtship and aggressive interactions;
and that urban males express lower colour contrast and were slower to change colours
than rural males. Using robotic lizard stimuli, I found that receiver responses
match population-specific intensity of male signals. Escape strategies of males, but
not females, also differed between urban and rural populations, such that urban
males were more tolerant of simulated predator attacks than rural males. As expected
from their cryptic body patterns, females regardless of habitat, relied more heavily
on crypticity rather than flight to minimize predation risk. Urban males also had
stronger cognitive skills, as spatial learning and reversal learning was faster than
in rural males. Along with these phenotypic shifts, stress physiology was also
affected, as urban males had significantly higher circulating corticosterone levels
than rural males. In sum, differences in these phenotypic traits between urban and
rural populations suggest human-induced changes in selective pressures that support
shifted survival and reproductive strategies.

The Asian Horned Frogs (Megophryinae: Megophryidae) are a taxonomically and systematically poorly known group of primarily montane specialist species. They are found throughout the southern Himalayas, central and southern China, Indochina, the Greater Sundas and the Philippines. I will present part of my PhD thesis work that aimed for the first time to elucidate the phylogenetic relationships and evolutionary history of Asian horned frogs based on the most taxonomically complete study of this group ever to have been attempted. Beside determining how species (and species groups) are related to each other, I will discuss how we overcame the problems of estimating ancestral divergence ages given the absence of a fossil record for this group, and the surprising results that might lead to a re-evaluation of divergence dates of other frog families. My work required a complete overhaul of horned frogs taxonomy, synonymising genera and identifying many currently unnamed ("new") species that have previously been hidden under "catch all" cryptic species complexes.

Smallholder agriculture will need to become much more efficient and precise in its use of water, energy, and chemical inputs if it is to become environmentally sustainable. However, diffusing efficient cultivation technologies among smallholders faces many social and economic challenges, requiring innovative solutions. I will describe some example and experiences from related field work in India around attempts to reduce water and nitrogen use, and opportunities for students to become involved in such research.
I will focus on emerging opportunities for Indian-Israeli collaboration in such research, including a summer program in Tel Aviv university that offers scholarships to selected Indian students.

Understanding how plant communities have been structured by past environments, and predicting how they might respond to future environmental changes, requires an understanding of plant strategies with respect to resource use, climate and disturbances. Functional traits are measurable morphological and physiological metrics that can be used to draw inferences about these underlying strategies.

In this presentation, I draw on examples from savanna-forest transitions across the globe to consider how the functional traits of tropical savanna and forest plants are indicative of growth and survival strategies that are shaped by their distinctive environments. I present some recent data on plant traits and disturbance regimes from some Indian savanna-forest transitions to contextualize these ecosystems in this comparative framework. I conclude with some unanswered and puzzling questions in these ecosystems.

The Iron Age-Early Historic burials, more popularly known as megalithic burials, attracted attention of archaeologists, historian and general public alike. These burials, often identifiable by certain patterns of arrangements of usually larger stones on the surface (hence termed megalith), are found across the landscapes in the five southern states of India. They are dated, through various methods, from as early as 2000 BCE to as recent as 600CE. The practice of raising these burials was associated with the beginning of Iron Age, following the Neolithic period in peninsular India.
My research primarily focuses on understanding the material culture of people of this period thorough examining these burials. The patterns of these burials with occasional discovery of artifacts provide us with a range of understanding not only about the cultural traditions of the period, but also about the nature of variation both within a site and across sites in landscapes. Drawing examples and inferences from my field research and excavation in a site in north Tamilnadu, I would reflect upon some of these questions in the talk. These burials have fascinated archaeologists for over 200 years due to their visibility on the landscape, but the questions regarding these burials remain numerous as it was centuries ago.

There are two main hypotheses describing tree grass coexistence in savanna. The first of these was proposed by Walter (1970) suggesting that trees obtain their resources from deep soil layers while grasses are more shallow rooted. The second hypothesis was proposed by Higgins et al (2000) suggesting that trees are prevented from reaching mature size classes through insufficient rainfall or alternatively through fire and herbivory. Our research in the Kruger National park has allowed us to examine these two hypotheses more closely giving us a much broader mechanistic understanding of savanna systems. We now believe that the availability of water and nutrients not only determine grass biomass but also grass species composition. Whether these are in South America, Australia or in southern Africa savanna soils are limiting in nitrogen and phosphorous and this means that both grasses and trees are rooted in the same soil horizons where nutrients are highest.
Grasses rather than trees are superior competitors for these resources and grasses are not affected by fire frequency but fire frequency does control tree biomass. How then do trees survive among competitively superior grasses? Trees avoid competition with grasses by leafing out early and taking up nutrients before grasses are able. Trees are able to establish when grass biomass is low through drought or intense grazing. Funding for the manipulative experiments necessary to develop this understanding was not possible without the Mellon Foundation and here I reflect on how this understanding was achieved over the last 15 years.

Predators impact prey populations not only by consuming individuals, but also by altering their behaviours. These non-lethal effects can influence food web properties as much as lethal effects. We studied the interaction between three ungulate prey species and gray wolves (Canis lupus) at multiple scales. First we found that bison (Bison bison) did not avoid areas where wolves spend most of their time, but instead, adjust their foraging behaviour to the level of risk. Second we evaluated the spatial game between radio-collared caribou (Rangifer tarandus), moose (Alces alces) and wolves. Both caribou and moose use several responses to the passage of wolves, including an increase in selection for food-rich forest stands. For example, caribou selected conifer stands with lichen more strongly for nearly 10 days following the passage of a wolf. We also showed how spatial patterns in predation risk, experienced by prey in a human-altered landscape, depend on how the other prey species respond to the same disturbance. Overall, our analyses demonstrate how the predator-prey game involves behavioural adjustments to the expectation of what the other player is most likely to do in a heterogeneous habitat.

It is a great pleasure to invite you for photography exhibition at CES where we will display pictures taken by Ecology students during their field work.
Please visit and enjoy beautiful pictures with sips of tea/coffee. You are welcome to have discussions with photographers and listen to the stories behind these pictures, straight from the horse's mouth.

Will be uploaded shortly

Recent mass livestock mortality, known as dzud, have called into question
the sustainability of pastoral nomadic herding, the cornerstone of
Mongolian culture. A total of 20 million head of livestock perished in the
mortality events of 2000-2002, and 2009-2010. We examine mortality in 21
Mongolian aimags (provinces) between 1955-2013 to explain its density
independent cause(s) related to climate variability. We show that
livestock mortality is most strongly linked to winter (November-February)
temperatures. Additionally, we find prior summer (July-September) drought
and precipitation deficit to be an important trigger for mortality that
intensifies the effect of upcoming winter temperatures. Our density
independent mortality model explains 48.4% of the total variability in the
mortality dataset.

Volcanic eruptions have global climate impacts, but their effect on the
hydrologic cycle is poorly understood. We use a modified version of
superposed epoch analysis, an eruption year list collated from multiple
datasets, and seasonal paleoclimate reconstructions (soil moisture,
precipitation, and temperature) to investigate volcanic forcing of spring
and summer hydroclimate over Europe and the Mediterranean over the last
millennium. In the western Mediterranean, wet conditions occur in the
eruption year and the following 3 years. Conversely, northwestern Europe
and the British Isles experience dry conditions in response to volcanic
eruptions, with the largest moisture deficits in post-eruption years 2 and
3. The precipitation response strongly resembles the negative phase of the
East Atlantic Pattern. Modulated through this mode of climate variability,
eruptions force significant, widespread, and heterogeneous hydroclimate
responses across regions of Europe with diverse precipitation
seasonalities.

We present a tree-ring reconstruction of Upper Indus River watershed flow
using hierarchical Bayesian regression (HBR). One distinct advantage of
HBR is that we can use partial pooling of information across multiple
streamflow gauges allowing us to reconstruct streamflow across a watershed
network (seven gauges), including at stations where streamflow records are
too short to reconstruct using traditional methods. We do this by
explicitly modelling the covariance structure of streamflow residuals and
regression coefficients across different gauges. Additionally, using
Bayesian methods we can develop reconstructions for gauge records with
missing data, which may be interspersed through the length of the record.
Consistent with a prior study we find that current flows since the 1980s
are higher than average for past five centuries, but may be comparable to
streamflow during the mid 1500s and late 1600s.