Neuroecology and neuroethology in Molluscs The interface between behaviour and environment

The term neuroecology was first coined in the 1980s and describes the ways in which species adapt to their environment both in the short term and in evolutionary time. Here, we focus on molluscan neuroecology to show how it interfaces with neuroethology and how animal behaviour adapts to environmental cues. neuroecology is thus meeting point between ethology, neuroscience, evolution, ecology, physics and chemistry. In this book, our contributors examine the concept of Neuroecology as applied to molluscs for the first time with particular reference to the areas of chemical ecology, predator prey relationships, neuroethology and evolution. Significant neuroecological progress has been made with a number of molluscan groups in terms of neurotoxic peptides, complex defensive ink alarm pheromones, bioaccumulation of shellfish toxins and the evolution of chemical defence mechanisms in species with reduced physical protection. Many molluscs inhabit a world of olfactory cues and their perceptions of the outside world are largely chemically driven, leading to odorant driven behavioural responses. This is important to both molluscan predators and prey and this area is explored in some detail with particular reference to gastropod molluscs. It is also true for cephalopod molluscs which although they have excellent vision, rely on distance chemoreception particularly prey perception, thus demonstrating their significance in affecting marine populations and communities. A better understanding the interactions of chemical cues between predator and prey molluscs will be important in future studies in the area of chemical ecology. Within the immune and neuroendocrine systems of molluscs the primary signalling molecules are exceptionally well-conserved and the pool of molecules used is similar to those in advanced vertebrates. This conservation of molecular systems is important in neuroecology and underlies the conservation of neural mechanisms underlying behaviours as organ systems alter under evolutionary pressure. Indeed, studies on pulmonates have shown that behavioural networks remain virtually intact during these processes, although reflecting the evolutionary changes that adapt the animal to its environment. Such networks exhibit plastic responses to allow for behavioural selection and seasonal change. However, studies on respiratory behaviour lead to the conclusion that many molluscs and other invertebrates are facing extinction because they cannot adapt their respiratory behaviour to the rapidly changing environmental conditions currently occurring particularly where hypoxia threatens the health of ecosysystems due to human activity. Such animals may prove to be sensitive models for studying the neuroecological effects of climate change with particular respect to invasive freshwater species such as predators, freshwater plans or microbial species. The challenge for the future is to utilise molluscan species research to illuminate the effects of environmental change on the neuroecology of these species, using them wherever possible to evaluate the degree of ecological change taking place. (Imprint: Nova Biomedica