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.
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.
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.