The Digestive Tract Of Cephalopods At The Interface Between Physiology And Ecology

Aristotle in the Historia animalium, (Book IV) gives one of the earliest descriptions of the anatomy of the cephalopod digestive tract, comparing it to that of other molluscs. From dissections of cuttlefish several key features of the cephalopod digestive tract were described: the beak (“teeth”) and radula (“tongue”), the passage of the oesophagus through the brain en route to the crop and stomach. The stomach is described as having spiral convolutions like a trumpet snail shell suggesting that the structure described is actually the caecum. The gut then turns anteriorly so that the anal opening is near the funnel leading a modern author to comment that they “defaecate on their heads” (Leroi, 2014). In the intervening two millennia research on the cephalopod digestive tract has been sporadic with much of the current knowledge arising from a series of studies in the 1950s to the 1970s by A.M. Bidder, E. Boucaud -Camou, R. Boucher-Rodoni and K. Mangold which established the basic mechanisms of digestion and absorption (e.g., Bidder, 1950; Boucaud-Camou et al., 1976). The last 10 years has seen a resurgence of research on the digestive tract stimulated by interest cephalopods (particularly Octopus vulgaris and Sepia officinalis) as candidate species for aquaculture and the potential impact of climate change on cephalopod ecology. Additionally, the inclusion of cephalopods in the European Union legislation regulating scientific research has necessitated improved understanding of dietary requirements and metabolism as well as the development of methods to monitor digestive tract function to ensure optimal care and welfare in the laboratory. Prompted by this resurgence of interest in the cephalopod digestive tract and an international workshop on the topic held in November 2015 we have collected a series of papers reflecting the current state-of-the art. The seventeen papers in this book combine original research publications and reviews covering a diversity of topics that are grouped under four main themes reflecting key topics in the physiology and ecology of the cephalopod digestive tract; feeding strategies, early life stages and aquaculture, anatomy and digestive physiology, care and welfare. This book provides a timely synthesis of ongoing research into the cephalopod digestive tract which we hope will stimulate further studies into this relatively neglected aspect of cephalopod biology. References Aristotle. The History of Animals, Book IV. Translated by D’Arcy Wentworth Thompson. Bidder, A. (1950). The digestive mechanisms of the European squids Loligo vulgaris, Loligo forbesii, Alloteuthis media and Allotuethis subulata. Q. J. Microscop. Sci. 91, 1-43. Boucaud-Camou, E., Boucher, Rodoni, R., and Mangold, K (1976). Digestive absorption in Octopus vulgaris (Cephalopoda: Octopoda). J.Zool.179, 261-271. Leroi, A.M. (2014). The Lagoon-How Aristotle Invented Science. Bloomsbury Circus, London.

The last five years have been extremely challenging, but also very innovative for cephalopod science, and the outstanding tradition of biological contribution with cephalopod molluscs as key players in science and human activities and interests has continued. This Research Topic is one of several dedicated to cephalopod molluscs (e.g., Hanke and Osorio, 2018; Ponte et al., 2018) hosted by Frontiers over the last few years, not to mention other papers published separately. Highlighting of cephalopod science is important because it has much to offer not only the life science community, but also more broadly the public perception of science and its understanding and relationship with scientific endeavour and cephalopods as living organisms and part of our everyday life (at least for most of us). This contribution illustrates the key needs that need to be overcome by the cephalopod research community, i.e. rapid and effective mechanisms for exchange of knowledge and resources, sharing of laboratory protocols, videos, tissues, samples and data-sets, innovative approaches and initiatives in public engagement. The cuttlefish comic included is an excellent example of a type of media that can be used to expand scientific knowledge to the public and human relationship with live animals. There are strategic challenges in convincing globally distributed policy makers and funders of the relevance of cephalopods in scientific advances, and also in the regulatory aspects, since cephalopods are the only invertebrates whose use is regulated in Europe in a research context and this increases the need for integrated oversight and direction in terms of ethics and animal welfare (e.g., Jacquet et al., 2019a; 2019b; Ponte et al., 2019). This Research Topic also aligns with the interests of the cephalopod community in stimulating public interest in cephalopods extending to a broader audience that could include chefs and gourmets, and fishers and scientists aiming to develop sustainable food resources. “CephsInAction: Towards Future Challenges for Cephalopod Science” Research Topic includes 14 papers from about 40 authors representing ten different countries, thus overlapping with the original parties that contributed to the COST FA1301 that, together with CephRes, promoted and supported this editorial initiative.

Squid, cuttlefish and octopuses, which form the marine mollusc group the cephalopods, are of great and increasing interest to marine biologists, physiologists, ecologists, environmental biologists and fisheries scientists. Cephalopods: ecology and fisheries is a thorough review of this most important animal group. The first introductory section of the book provides coverage of cephalopod form and function, origin and evolution, Nautilus, and biodiversity and zoogeography. The following section covers life cycles, growth, physiological ecology, reproductive strategies and early life histories. There follows a section on ecology, which provides details of slope and shelf species, oceanic and deep sea species, population ecology, trophic ecology and cephalopods as prey. The final section of the book deals with fisheries and ecological interactions, with chapters on fishing methods and scientific sampling, fisheries resources, fisheries oceanography and assessment and management methods. This scientifically comprehensive and beautifully illustrated book is essential reading for marine biologists, zoologists, ecologists and fisheries managers. All libraries in universities and research establishments where biological sciences and fisheries are studied and taught should have multiple copies of this landmark publication on their shelves.

A fully updated overview of the causation, function, development and evolution of cephalopod behaviour, richly illustrated in full colour.

Molluscs comprise the second largest phylum of animals (after arthropods), occurring in virtually all habitats. Some are commercially important, a few are pests and some carry diseases, while many non-marine molluscs are threatened by human impacts which have resulted in more extinctions than all tetrapod vertebrates combined. This book and its companion volume provide the first comprehensive account of the Mollusca in decades. Illustrated with hundreds of colour figures, it reviews molluscan biology, genomics, anatomy, physiology, fossil history, phylogeny and classification. This volume includes general chapters drawn from extensive and diverse literature on the anatomy and physiology of their structure, movement, reproduction, feeding, digestion, excretion, respiration, nervous system and sense organs. Other chapters review the natural history (including ecology) of molluscs, their interactions with humans, and assess research on the group. Key features of both volumes: up to date treatment with an extensive bibliography; thoroughly examines the current understanding of molluscan anatomy, physiology and development; reviews fossil history and phylogenetics; overviews ecology and economic values; and summarises research activity and suggests future directions for investigation. Winston F Ponder was a Principal Research Scientist at The Australian Museum in Sydney where he is currently a Research Fellow. He has published extensively over the last 55 years on the systematics, evolution, biology and conservation of marine and freshwater molluscs, as well as supervised post graduate students and run university courses. David R. Lindberg is former Chair of the Department of Integrative Biology, Director of the Museum of Paleontology, and Chair of the Berkeley Natural History Museums, all at the University of California. He has conducted research on the evolutionary history of marine organisms and their habitats on the rocky shores of the Pacific Rim for more than 40 years. The numerous elegant and interpretive illustrations were produced by Juliet Ponder.

Octopus Biology and Ecology is an all-in-one resource that explains early life history stages, including age and growth maturation, distribution, migration, diet, predators and parasites related to these mollusks. Octopods are becoming a strong source of protein, with information on the species becoming more and more important to fisheries. This reference offers detailed information on the most economically important octopods in the world and addresses the management and future forecasting of octopod fisheries. Special attention is given to octopods in highly variable coastal environments as they constitute a particular challenge. Octopod populations (together with other cephalopod groups) have increased worldwide, suggesting that these commercially relevant mollusks will benefit from the conditions of the oceans of tomorrow (e.g., global warming and decreased competition and predator pressures). This is a complete resource for aquatic scientists, marine biologists, researchers, cephalopod biologists, cephalopod ecologists, fisheries and aquaculture scientists, regulators and students. ? Provides a thorough overview of the biodiversity of octopuses ? Presents a detailed information about 21 different species ? Includes a profound analysis of past, present, and future trends in octopus research

The aim of this open access book is to facilitate the identification and description of the different organs as well as pathogens and diseases affecting the most representative species of cephalopods focussed on Sepia officinalis, Loligo vulgaris and Octopus vulgaris. These species are valuable ‘morphotype’ models and belong to the taxonomic groups Sepioidea, Myopsida and Octopoda, which include most of the species with a high market value and aquaculture potential. The study is based on photographs at macroscopic and histological level in order to illustrate the role of the most important pathogens and related diseases from the view of a pathological diagnosis. The reader is able to familiarize with functional anatomy, necropsy and general histology of adults and paralarvae, as well as with the identification of different pathogens and pathologies. This work is thus an invaluable guide for the diagnosis of cephalopod diseases. Besides including pathogens for non-European cephalopod species, it also provides a useful contribution encouraging marine pathologists, parasitologists, veterinarians and those involved in fishery sanitary assessments, aquarium maintenance and aquaculture practices aiming to increase their knowledge about the pathology of cephalopods.

Focusing on comparative cognition in cephalopods, this book illuminates the wide range of mental function in this often overlooked group.