Introduction to the Nigel Barlow Symposium

Dr Nigel Barlow died on 4 June 2003 aged 53 in Christchurch, New Zealand. Nigel completed his PhD at the University of East Anglia in 1977 and emigrated to New Zealand in 1979 where he worked initially at Palmerston North and for the last 12 years for AgResearch at Lincoln. Nigel made an enormous contribution to New Zealand ecological science through the use of mathematically based models. In particular, he worked on insect pests such as grass grubs and vertebrate pests such as possums and rabbits, producing over 130 papers. Nigel’s models of bovine tuberculosis underpinned the current strategies and expenditure of over $50 million each year on the control of wildlife vectors on this disease. Nigel’s capabilities as a scientist were not only in the applied field but also reflected in his ability to win funds with his student John Kean from the prestigious Marsden Fund for basic research on the causes of rarity. He was Editor of the New Zealand Journal of Ecology from 1985 to 1990 and of the Journal of Applied Ecology. Nigel was awarded the New Zealand Ecological Society Award for his outstanding contribution to applied ecology in 1996 and posthumously in 2003 the Caughley Medal for lifetime contributions to wildlife management and ecology by the Australasian Wildlife Management Society. Nigel was a true polymath and enthusiast about all natural history. He had an interest in bird-winged butterflies and regularly vanished into the jungles of Indonesia and Papua New Guinea to study them. He was fascinated by crocodilians and anacondas, mountain climbing, landscape painting, and malt whisky. At work he was resistant to bureaucratic interference but happy to pass on his abilities and insights to his students and numerous colleagues.     

Evolution of Starfishes: Morphology, Molecules, Development, and Paleobiology. Introduction to the Symposium

Among starfishes, fascinating life cycles and complex morphologicalpatterns have evolved within a familiar but unusual basic bodyplan. In spite of these rich complexities, available phylogeneticinterpretations conflict, and the history of this importantgroup remains uncertain. The symposium brought together currentperspectives on phylogeny, the implications of certain poorlyknown aspects of asteroid morphology, and consideration of significantevents that preceded the diversification of extant asteroidgroups in the Mesozoic. It has become axiomatic in modern organismal biology that stronglysupported phylogenetic reconstructions are crucial to the understandingof biological pattern and progress. Although asteroids exhibitcomplex morphologies, life cycles, and behaviors that indicatetheir status as ideal model organisms in the study of marineinvertebrates, their evolutionary history remains obscure. Thisis in part due to a lack of treatment by researchers but alsoin part due to inherent limitations of the available data. In the following pages, the state of inquiry into the studyof relationships among starfishes is arranged in three sections:the nature of the fossil record (an introduction to modern starfishes),taxa and morphology, and phylogenetic interpretations.     

Introduction to the Symposium: What is Computational Neurobiology?

SYNOPSIS. Current advances in computational biology are derivedfrom two sets of ideas established in the work of Santiago Ramóny Cajal. One is the neuron doctrine, which holds that neuronsare the functional units of the nervous system, and has ledto detailed models of neuronal properties based on increasinginformation on the physical and chemical properties of neurons.The second is the idea of networks of neurons with specificpatterns of interconnections that has led to a variety of mathematicalmethods of analyzing such networks. Future work in computationalneurobiology promises to be a blend of these two modeling approaches.     

How to Win the Evolution War: Teach Macroevolution!

If the American public understood what is actually known about the major evolutionary transitions in the history of life and how we know about them, uncertainty about evolution would drop precipitously, creationist arguments would fall on deaf ears, and public education in biology would make much more sense than it now does. Macroevolution must take a much more prominent place in K-12 science teaching. To do so, a curriculum must be redeveloped at both K-12 and college levels, so that preparation in macroevolution is a required part of K-12 biology preparation.     

Macroevolution: macrogenesis and typogenesis

One can distinguish two levels (and stages) of macroevolutionary processes: the lower (macrogenesis) and higher (typogenesis) ones. The macrogenesis represents macroevolutionary alterations of separate structures; the typogenesis is the forming of general Bauplan (type of organization) of a new macrotaxon on a base of initial macrogenesis. Discrete (or quantum) character of many macroevolutionary transformations is caused by various mechanisms, which are based on properties of integrated organismic systems and are characterized by threshold effect of their action. Initial macrogenesis can be resulted from the morphofunctional preadaptations; the pattern (or regime) transformations of morphofunctional organismic systems; emerging of dichotomy of morphogenetic programs and their following switching; the ontogenetic heterochronies (in particular, paedomorphosis); the allometric structural changes (and possibly some other mechanisms). The initial macrogenesis forms a base for qualitatively new adaptation and essentially influences on other systems in whole organism. That changes the selection vectors significantly. All these alterations trigger the typogenesis. The latter represents a complex of organismic systems transformations, integrated by selection and interconnections of various systems in whole organism. The important role in typogenesis belongs to the key alterations of some limiting organismic system that trigger and direct evolutionary changes of depended organismic systems. In course of typogenesis evolution, new macrotaxon occupies new adaptive zone.     

Introduction to the Symposium: Territoriality: Conceptual Advances in Field and Theoretical Studies

This symposium was convened to synthesize recent advances indeveloping and testing quantitative and qualitative models ofterritoriality. The goals were to increase the rigor of currentmodels of territoriality, to put field data into a conceptualframework, and to involve a variety of taxa so as to obtaina breadth of perspective not previously available.     

Hormonal Control of Growth and Reproduction in the Arthropods: Introduction to the Symposium

SYNOPSIS. An overview of hormonal control of growth and reproductionin the arthropods is presented.     

Introduction to the Symposium: Ontogenetic Strategies of Invertebrates in Aquatic Environments

This symposium presents different ecological and physiologicalstrategies used by invertebrates to successfully adapt to aquaticenvironments. Adaptation has been studied mainly in adult animals,but the papers comprising the symposium emphasize ontogeneticstrategies, starting from the principle that natural selectionacts on all stages of development. Adaptive strategies may thusdiffer strikingly between developmental stages of the same organism.Invertebrates offer a wide array of ecophysiological modelsfor study, and these are exemplified by the contributions tothe symposium, which are briefly summarized. Future researchin the field will 1, expand the number of models for comparativepurposes; 2, examine the strategies, not only of larvae andjuveniles, but also of embryos, eggs and reproductive cells;and 3, investigate the genetic basis of ontogenetic strategies.     

Macroevolution: The Morphological Problem

The central question of macroevolution concerns the evolutionof major morphological innovations (and major taxonomic groups).It is a matter of scale rather than simply rate of evolutionor hierarchical level of mechanism. Through the history of microevolutionarytheory there is a constant counterpoint of macroevolutionaryquestioning: are current versions of microevolution sufficientto explain the data concerning origins of major novelties? Thus,Simpson proposed the term "megaevolution" and "quantum evolution."Mayr partially separated micro- and gradual aspects by proposing"genetic revolution" as a mechanism for rapid change. Evolutionarytheory in general suffers because different concepts have incompatibleframes of reference. Key innovation and correlated progressionare concepts that approach the problem in terms of evolutionarymorphology. They have in common with quantum evolution and geneticrevolution features such as threshold effect, preadaptationand smooth transition due to change in function and environment.One aspect of paleontology and morphology, however, is to showthat some morphologies can only exist in binary states, withno intermediates. This leads us to look away from selectionon graded series of phenotypes to development (developmentalcascade/threshold models) for new levels of explanation.