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The chimpanzees of Bossou are known to use the stone tools to crack open the oil-palm nuts. This is the unique cultural behavior of the community. I have studied the community for the past 3 decades
since 1986. The talk will highlight the past, present, and future of the unique chimpanzees. The conservation effort is called "Green corridor project" that is planting trees in the savanna. I have been doing the parallel effort of fieldwork and laboratory work on chimpanzees. Please take a look at the following site for the information: http://langint.pri.kyoto-u.ac.jp/ai/ Based on the accumulation of the primatology, my colleagues and me has started a new discipline called "Wildlife science" that deals the endangered non-primate large animals in their natural habitats. Please take a look at the following site too.
http://www.wildlife-science.org/index-en.html
Darwin’s ‘entangled bank’ captured the principle that species in nature must manage complex interdependencies to successfully coexist in natural communities. Despite great advances in the study of intricate ecological networks, we still do not know what the entangled bank looks like, nor if evolutionary restrictions create pattern in the multidimensional niche structure of communities. Disentangling the bank requires building comprehensive ecological networks which synthesize all known species interaction types (e.g., predation, competition, facilitation) as well as developing statistical methods for discovering pattern in such multiplex systems. We studied connectivity in a comprehensive ecological network using novel network models. We show that the network exhibits clear patterns at different organizational levels and ultimately collapses into a small set of 'functional groups' that are taxonomically coherent. This suggests that the iconic complexity of ecosystems may simplify into fundamental building blocks of nature.
Animal venoms 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 of animals. Not surprisingly, the evolution of venom, one of nature’s most complex biochemical concoctions, has underpinned the predatory success and diversification of numerous animal lineages. Animal venoms provide unparalleled models for understanding molecular adaptations associated with predator-prey interactions and the convergence of biochemical functions. Venoms are theorized to evolve under the significant influence of positive Darwinian selection in a chemical arms race scenario, where the evolution of venom resistance in prey and the invention of potent venom in the secreting animal exert reciprocal selection pressures. However, the dynamics of venom evolution and the mechanistic insights into the molecular changes that confer toxin resistance mostly remain elusive. We provide evidence of surprisingly constrained parallel molecular evolution across the animal kingdom, where the resistance to toxic cardiac glycosides produced by plants and bufonid toads is mediated by similar and predictable molecular changes to the sodium-potassium-pump (Na+/K+-ATPase) in several lineages of insects, amphibians, reptiles and mammals.
Understanding the genetic basis of the diversification of venom encoding genes in animals can provide fundamental biological insights into their species evolution, ecological specialization and genetic novelties, which may be of further importance for antivenom, pesticide development and drug-discovery research. However, venom research has mostly neglected ancient animal groups, such as spiders and centipedes in favour of focusing on venomous snakes and cone snails that originated relatively recently in the evolutionary timescale (~50 million years ago). By analysing over 3500 sequences from 85 toxin families in both ancient and evolutionarily young animals, we propose a new model of venom evolution that describes how venomous animals respond to evolutionary arms races and the significant shifts in ecology and environment. Our ‘two-speed’ model captures the fascinating ‘rise and fall’ in venom evolution.
Although the dire effects of malnourishment on an individual has
been well documented across taxa, considerably little is known if
populations can adapt to chronic malnutrition over several generations,
the adaptive traits that facilitate such tolerance and the associated
trade-offs. We used an experimental evolution approach involving replicate
populations of Drosophila melanogaster (over 190 generations) to
investigate the life-history and behavioural consequences of adaptation to
larval malnutrition. We found that the ability to cope with malnutrition
leads to several adaptations that impinge upon diverse aspects of
structure, function and life-history of the fly. However, this
malnutrition tolerance is costly, increasing susceptibility to intestinal
pathogens and reducing fecundity. Interestingly, this investigation also
led to the discovery and detailed study of two novel larval behaviours:
predatory larval cannibalism and prepupal tunnel building. Furthermore,
these experimentally evolved populations have raised important questions
on the evolution and maintenance of traits that regulate nutritional
homeostasis in an organism.
Many ecosystem services derived from soils depend on their capacity to store organic matter. The aim of this talk is to present results from recent studies concerning biological as well as physico-chemical mechanisms leading to C gain or loss from soils. The importance of stabilisation processes for elevated residence times of bulk soil organic matter (SOM) and specific molecular compounds in different parts of the soil profile will be highlighted. I will present recent advances and changing paradigms concerning the composition and origin of stabilised SOM. Moreover, I will discuss the influence of biological factors, such as microbial diversity and faunal activity on these processes.
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Can animals have history? After all, the sense of history is assumed to be a part of what makes us uniquely human. Yet, the story of the lions of Gir, now over 500 in number with a range four times what it was a decade ago, gives cause for a cautious rethink.
On the brink of extinction around 1900 in their last forest home in Asia, they recovered under selective protection by princes, the Empire and in independent India. Since hunting ended in the 1950s, there has been a major change in lion behaviour. Far more than in the past and possibly unlike any other big cat population in the wild they often allow humans to come very close on foot. There are conflicts and there have been two instances of "lion plague" but these need to be set against a wider canvas of a remarkable human-animal interaction.
The remaking of carnivore-human interactions has entailed adaptation and change on the part of both. How should these be viewed historically? Peter Boomgaard in writing of tigers in the Malay world (where they were mostly wiped out) spoke of the tigers as "political animals" whose behaviour and habits were deeply conditioned by specific histories they shared with humans. But do the Gir lions merge as actors or actants in a history? Are they products of the historical process or makers of it even if in a very specific sense?
These questions require reflection even if there is no easy answer. They also make us rethink not only what it means to be animal but also what constitutes the human in the world of today.
Survival and adaptation of plants in their habitats involve sophisticated ecological events. For example, when attached by herbivores, elicitation of defense responses involves perception, processing and integration of external information into cellular and physiological machinery, ultimately leading to a massive molecular reprogramming. Except for the involvement of some transcription factors (TFs), a few imbedded in MPAK pathway, how defense signaling is modulated remains poorly understood. Regulatory small RNAs (smRNAs) have appeared as master regulators in cellular processes both in prokaryotes and eukaryotes. Information on their involvement in regulating plant defenses during herbivore attack is still limited. In our studies we are attempting deconvolution and reconstruction of a smRNA pathway that functionally regulates induced plant defenses. The evolution of smRNA-pathway effectors, the AGOs, is a dynamic process that could generate signatures of diversification of function of smRNA pathways in plants. Understanding molecular evolution of these components of smRNA machinery is providing further insights into mechanistic details of recruitment of specialized smRNAs. We are further expanding our studies to determine how such processes have responded to evolutionary pressures of polyploidization and domestication that have shaped agriculture, and in turn modern civilization.
The present distribution and co-occurrence of trees in the Western Ghats is determined by environmental drivers and biotic interactions operating over a hierarchy of spatial and temporal scales, from local sets of individuals to the regional pool of extant taxa. The French Institute of Pondicherry has conducted extensive characterization and mapping of the diversity of forest types in the
Western Ghats, and also characterized and monitored the long-term dynamics of local communities. From this rich information, it is time for us to address the determinants of the diversity and predict the dynamics of these forests across spatial scales.
Our main objectives are therefore: (i) to address the drivers of taxonomic, functional and phylogenetic diversity of forests over a broad environmental gradient, using cutting-edge theories and methodologies, (ii) to understand the origins of the extant pool of taxa, and how endemics have evolved in diverse niches.
Bringing together complementary skills and mutual interests of research teams working on biodiversity in the Western Ghats is an exciting and promising perspective. It will allow tackling the great challenge of better understanding the past and present of our legacy, as well as to predict its future in the face of intensive global changes.