bluuebunny/crossref_metadata_2025 huggingface dataset:
On the relative importance of direct versus indirect effects in ecological communities
Authors: Schoener Thomas W
Published: November 2023

The science of ecology is becoming increasingly complex. Theoreticians are telling us that we can expect a variety of important indirect effects in food webs, some of them over fairly long pathways, at least in models with random interaction coefficients and sometimes with real ones. Experimentalists, discovering new techniques and working harder and longer, are beginning to uncover indirect effects in fair number. Although they will never be able to investigate the full scope of complexity available to theoreticians, there is some feeling, perhaps fear, that this is the tip of the iceberg We are presently trying to determine how important indirect effects are, and how indirect they can be and still be important. This issue can be cast precisely in two ways First, pick two species in a community of interacting species. To what extent does the net or total effect of one on the other, in terms of sign and magnitude, depend on a direct effect component v. effect components of varying degrees of indirectness — how much do distant species matter? Secondly, perturb a given species.
Early Vertebrates
Authors: Janvier Philippe
Published: November 2023

This book presents our current knowledge of the early vertebrates, which were mainly fish, but included some land vertebrates, and lived about 470 to 250 million years ago. It centres on anatomical and phylogenetic questions, but includes information about fossil discovery and preparation, as well as the analysis of the characteristics from which their relationships may be reconstructed. It addresses critically both old and new problems in the evolution of certain anatomical structures and deals briefly with the animals' way of life, extinction, and former distribution. In addition, the author gives a potted history of the field of vertebrate palaeontology and the rise of cladistics, a major methodological revolution in comparative biology. The book is the first in theif field to use a cladistic approach. For each major vertebrate group, the reader will find a diagram of relationships, or cladogram, with a selection of characters at each node, and a cuccinct phylogenetic classification. The book is illustrated with numerous line drawings, culminating in a series of reconstructions of early vertebrates and their environment, which may have a more popular appeal.
Derivation of the exhalations
Authors: Stanton R L
Published: November 2023

There seems no reason to doubt* that de Beaumont and de la Beche assumed the ore-bearing emanations to result from degassing of the associated molten volcanic rocks, and hence to have a common, deep, origin with the latter. Indeed, in differing from the views of Werner, de Beaumont asserted that ‘One admits with him that mineral substances have been deposited by the action of waters ... but one does not admit that it may have been by supergene solutions; one considers, on the contrary, that the substances spread on the surface have come from the interior of the earth ... ‘ (de Beaumont 1847, p. 1284). One possible deviation from this assumption was the statement by N. H. and H. V. Winchell, in connection with the origin of the Lake Superior banded iron ores, that sea water, on encountering recently erupted basalts, would ‘... become surcharged with soluble silica and iron, obtaining the latter from the augitic minerals of the basic lavas, and possibly from masses of erupted metallic iron’ (Winchell and Winchell 1891, p. 396).
Sundry elements
Authors: Stanton R L
Published: November 2023

All the Solomons lavas of present concern contain, in addition to the trace elements considered in Chapters 6-19, very small quantities of elements such as cadmium, gallium, gold, silver, tungsten, uranium, and others that also commonly occur as minor to trace components of exhalative ores. They also contain varying, very small, amounts of sulphur. In addition they contain traces of elements such as rubidium, zirconium, and thorium, which, through their often highly systematic abundance relations with the traces of the ‘ore elements’ serve to emphasize the intimacy of the tie between the incidence of the latter and the geochemical and mineralogical evolution of the relevant lava systems.
The diversity of fruit fly (Diptera: Tephritidae) parasitoids
Authors: Hoffmeister Thomas S , Vidal Stefan
Published: November 2023

Three decades ago Hutchinson (1959) asked in his influential paper on niche differentiation and community structure ‘Why are there so many kinds of animals?’. Since then the diversity of species sharing the same resources, or in the case of parasitoids sharing the same hosts, has attracted increasing interest. Strong et al. (1984) discussed the major determinants of diversity in herbivorous insects, but only in recent years have patterns emerged on how life history traits of hosts shape the composition and diversity of their parasitoid communities (e.g. Askew and Shaw 1986). Subsequently, patterns have been studied at various levels, ranging from global (Hawkins 1990) to regional (Hawkins and Lawton 1987; Hawkins 1988a), and parasitoid complexes of exposed versus concealed herbivores have been compared (Hawkins 1988b; Price and Pschorn-Walcher 1988).
Patterns of parasitoid accumulation on introduced herbivores
Authors: Cornell Howard V , Hawkins Bradford A
Published: November 2023

Most of what we know about the structure of parasitoid communities comes from the examination of native host-parasitoid systems. More can be learned by studying parasitoid assemblages associated with hosts introduced into foreign locations. Such introductions can often be treated as natural experiments to test ideas about the assembly of ecological communities (Elton 1958; Diamond 1986). Surveys of many such introductions and their outcomes make it possible to profile successful invaders as well as their impacts on local communities (e.g. McDonald et al. 1986; Mooney and Drake 1986; Crawley 1987; Drake et al. 1989; Simberloff 1991).
The use and construction of parasitoid webs
Authors: Memmott J , Godfray H C J
Published: November 2023

This chapter is composed of two parts. In the first we argue that the construction of parasitoid webs offers the best prospects of advancing parasitoid community ecology, and also provides the hope of linking this field of parasitoid biology with other areas, such as population dynamics and behavioural ecology. At once we must declare an interest-our recent research activities have involved the construction of parasitoid webs-we are not exactly disinterested observers. In the second part we describe the construction of a parasitoid web centred around the leaf-mining insects of regenerating tropical dry forest in Costa Rica. We hope our experiences may be of use to workers building parasitoid webs involving other groups of hosts and parasitoids.
African fig wasp parasitoid communities
Authors: Compton Stephen G , Rasplus Jean-Yves , Ware A B
Published: November 2023

What are fig trees and fig wasps? Fig trees are a group of approximately 850 species placed in the genus Ficus (Moraceae), and are characterized by their unique inflorescence-the fig. Around 105 Ficus species are found in Africa, where they range in size from small shrubs to huge rain forest emergents (Berg 1990; Berg and Wiebes 1992). The term ‘fig wasps’ is sometimes applied to all the hymenopterans that develop inside figs, but more often is restricted to certain chalcid wasps (Hymenoptera, Chalcidoidea), the taxonomic placement of which has changed considerably in recent years (Table 18.1). At present, the fig wasps previously placed in the families Agaonidae, Pteromalidae, and Torymidae are all considered to belong to a single family, the Agaonidae (Boucek 1988). All agaonid species are associated exclusively with fig trees.
Building parasitoid communities: the complementary role of two introduced parasitoid species in a case of successful biological control
Authors: Takagi Masami , Hirose Yoshimi
Published: November 2023

It has now been just over a century since the successful control of the cottony cushion scale after the introduction of the vedalia beetle from Australia into California. Following this initial success, about 4300 introductions of natural enemies against insect pests have been attempted (Waage 1990; Godfray and Waage 1991), and some of them have resulted in spectacular successes. However, most attempts have not succeeded because of failures in establishment of the natural enemies or insufficient reduction of pest densities. To improve the success rate for classical biological control, a more scientific approach should be adopted in the selection of natural enemies for introduction. Ecologists and population biologists as well as biological control workers have been concerned with introduction strategies in classical biological control (Ehler 1990, Chapter 21). One long-standing debate on introduction strategies has been that between the ‘multiple species introduction’ and ‘single species introduction’ schools.
The implications of population dynamics theory to parasitoid diversity and biological control
Authors: Hochberg Michael E , Hawkins Bradford A
Published: November 2023

Insect parasitoids constitute an important and diverse group of taxa. Recent estimates indicate an average of about five to six parasitoid species per insect herbivore species (Askew and Shaw 1986; Hawkins and Lawton 1987; Hawkins 1990; Mills 1992, Chapter 3), although the range extends to almost 100 species (Delucchi 1982). Explaining this range in richness is an important challenge to community ecology. Comparative studies have shown how host feeding niche contributes substantially to explaining variation in parasitoid richness (Hawkins and Lawton 1987; Mills 1993; Hawkins 1993a). Feeding niche has been interpreted as a mechanism generating a ‘refuge’ for those host individuals that are sufficiently (and best) protected from parasitoid attack (Simmonds 1948; Gross 1991; Hawkins and Gross 1992; Hawkins 1993a).
Parasitoids as model communities in ecological theory
Authors: Lawton John H
Published: November 2023

I recently lectured to some 200 new undergraduates about to embark on a biology degree course. One of my themes was parasitoid diversity, and sensing that my young listeners were not entirely turned on by parasitoids, I stopped lecturing and asked how many in the audience had actually seen a parasitic wasp? The answer was four, and one of those wasn’t sure. Undeterred, I then foolishly asked how many knew what parasitoids were, and what they looked like, despite the fact that very few had actually seen one of these remarkable little creatures? Back came the show of hands-11 of them. From then on the lecture was, as they say, dead in the water. I might as well have been talking about little green men from Mars.
Interacting metapopulations and metacommunities
Authors: Hanski llkka
Published: November 2023

Two or more species can live in the same patch network without any interactions among the respective metapopulations. More interestingly, interspecific interactions might affect the rates of migration, extinction and colonization, in which case interspecific interactions modulate metapopulation dynamics of the species concerned. Extinction rates might become elevated, but local interactions between the species may also enhance metapopulation persistence by increasing asynchrony in local dynamics. An important recurring theme in the dynamics of two or more interacting metapopulations is the creation and maintenance of aggregated spatial distributions of species in the absence of any environmental heterogeneity. In singlespecies metapopulations, where extinctions are due to external perturbations, increased migration rate is generally beneficial for long-term persistence in facilitating colonization, with the caveat that too much is too much: massive emigration and high mortality during migration may increase extinction rate so much that metapopulation persistence is reduced.
Badger sociality—models of spatial grouping
Authors: Woodroffe Rosie , Macdonald David W
Published: November 2023

European badgers (Meles meles L.) are unusual amongst carnivores in that they form large groups, sharing a territory and a communal den, but forage alone on small prey. There is very little evidence of co-operative behaviour, raising the question of why groups form. Most discussions of group living in non-co-operative carnivores have concentrated upon group territoriality, suggesting circumstances under which territory holders might benefit from allowing other animals to share their territories. One family of models, the Resource Dispersion Hypotheses (RDH), demonstrates that the rule which a primary territory holder uses to choose a minimum territory, in a world where food is patchily distributed in space and time, can allow additional animals to share the territory at little or no cost to the territory holder. Another model, the Prey Renewal Hypothesis, shows more generally how rapid prey renewal may allow several animals to share a home range. Finally, the Territory Inheritance Hypothesis (TIH) suggests that territory holders might allow their offspring to share the territory if the possibility of inheriting this resource would enhance their future reproductive success.
Foraging strategies of shrews: interactions between small predators and their prey
Authors: Churchfield Sara
Published: November 2023

Foraging strategies of Sorex araneus and S. minutus were investigated by examining the diets of wild shrews together with the biomass and numbers of prey available. By having diverse diets, shrews had access to an abundant food supply throughout the year. But they needed to catch prey at a high rate to satisfy daily energy requirements, with an estimated daily intake of 566 prey by S. araneus and 247 prey by S. minutus. With the exception of Coleoptera and Isopoda, energy values of prey varied little and are unlikely to be the basis of prey selection by shrews. Rates at which prey were encountered were found to be more important in determining diets of shrews than selection based on prey size or food value.
Social organization in martens: an inflexible system?
Authors: Balharry David
Published: November 2023

The variability in the social organization of carnivores is attributed in some species to the distribution of key resources. Previous research on martens suggested an intrasexually determined territorial organization for the species. In this study martens at high and low density were studied. Twenty-four animals were radio-tracked and their social status was determined by aging, hormone analysis and gland measurements. Radio-isotopes were used to determine the presence of martens not captured. The social organization of martens at different densities was shown to conform with the results of previous studies. Range size of females was not determined by peripheral resource-rich patches. It is suggested that the distribution of resources would not support additional animals at a low cost to the territory holder. Additional conspecific adults were not tolerated although young martens were. While the results do not contradict the hypothesis that the spatial organization of these carnivores is determined by the dispersion of resources, it is suggested that group living in martens may be prevented by phylogenetically determined intolerance of conspecifics.
Use of molecular probes to analyse pilot whale pod structure: two novel analytical approaches
Authors: Amos Bill
Published: November 2023

DNA fingerprinting can be used to answer many questions in behavioural ecology. However, where the number of crosswise comparisons to be made is large, as in the study of genetic relationships within a group, single locus analysis is often preferable. Furthermore, the study of group structure is often complicated by the difficulty of defining a population mean. Two analytical approaches are presented which have been designed to circumvent this problem: one derives an estimate for the number of individuals accompanied by one or other parent, the other tests for strong philopatry. The two methods are investigated by means of computer simulations and, although applicable to other species, are illustrated with an analysis of pilot whale pod structure. Both appear to provide useful information concerning relatedness within the group.
Sex differences in diving and foraging behaviour of northern elephant seals
Authors: Boeuf B J Le , Crocker D E , Blackwell S B , Morris P A , Thorson P H
Published: November 2023

Sex differences in the foraging behaviour of adult northern elephant seals, Mirounga angustirostris, are predicted from the great disparity in size between the sexes, males being 1.5-10 times larger than females. Males must consume approximately three times more prey per day than females. By examining the diving behaviour, during which all foraging occurs, our aim was to elucidate how males do this and when the strategy develops. Dive data were collected by microcomputer time-depth recorders attached to the backs of free-ranging seals (nine adult males, 10 adult females, seven juvenile males and six juvenile females) during periods at sea ranging from one to three months. The sexes foraged in different locations and exhibited differences in foraging-type dives, suggesting different foraging strategies and, possibly, different prey. Females moved steadily across the north-eastern Pacific from the coast to as far as 150 °W, in the range 44-52 °N, foraging daily en route. Males migrated to areas along continental margins off the state of Washington, to as far as the northern Gulf of Alaska and the eastern Aleutian Islands, where they exhibited concentrated foraging.
Grey seals off the east coast of Britain: distribution and movements at sea
Authors: Hammond P S , Mcconnell B J , Fedak M A
Published: November 2023

As part of a programme of research to investigate the interactions between marine mammals and their environment, the SMRU has been studying the distribution and movements of grey seals off the east coast of Britain. Three approaches have been employed: monitoring from Automatic Recording Stations using VHF telemetry; continuous tracking from a yacht using a combination of VHF and underwater ultrasonic telemetry; and satellite-link tracking through Service Argos. The three different methodological approaches allow investigations from different perspectives. VHF monitoring gives data for up to a year on the presence/absence of animals at sites close to the coast; the use of a number of sites provides information on seal movements between them. Satellite-link tracking gives detailed data for up to several months on the location of seals, wherever they go. Continuous ultrasonic/ VHF tracking gives detailed records of movements and behaviour of seals for short periods of up to about ten days. The information on diving behaviour provided by real-time and satellite tracking is presented elsewhere; here we concentrate on the horizontal distribution and movements.
Siliceous microfossils
Authors: Jones Robert Wynn
Published: November 2023

This chapter deals with siliceous microfossils. These range in size from 5-20000 µ. Preparation of samples for siliceous microfossil study generally consists of physical disaggregation of containing sediment followed by hydrogen peroxide oxidation of organic material and acetic (ethanoic) or hydrochloric acid leaching of calcareous material and sieving. Heavy liquid flotation techniques can also be used, although they can be hazardous to health (commonly used chemicals such as carbon tetrachloride (tetrachloro ethane) being carcinogenic) and, moreover, are ineffective in the not uncommon event of the original silica having been replaced by pyrite. The final concentrate is made up in a strew slide for examination under a transmitted light microscope. Canada Balsam is a commonly used mounting medium.
Biostratigraphy and palaeoenvironmental interpretation
Authors: Jones Robert Wynn
Published: November 2023

This chapter contains sections on biostratigraphy and palaeoenvironmental interpretation. The section on biostratigraphy includes a subsection on quantitative biostratigraphy. The section on palaeoenvironmental interpretation includes some preli nary observations on benthonic foraminifera associated with petroleum seeps.

The summary stratigraphic ranges of the major microfossil groups discussed in Chapters 2-6 are shown on Fig. 7.1. The ranges over which they are stratigraphically useful are indicated by broad bands. It is evident that most are only useful over certain time intervals and then only in the appropriate facies (see Section 7.4).
Integrated stratigraphy
Authors: Jones Robert Wynn
Published: November 2023

This chapter contains sections on sequence stratigraphy (in both elastic and carbonate systems), absolute chronostratigraphic time-scales and stratigraphic controls on hydrocarbon habitat. The sections on elastic and carbonate sequence stratigraphy include subsections on the micropalaeontological characterisation of systems tracts.
An Introduction to Optical Dating
Authors: Aitken M J
Published: November 2023

Optical dating is a rapidly developing technique, used primarily in the dating of sediments deposited in the last 500,000 or more years. As such increasing numbers of Quaternary geologists, physical geographers, archaeologists, and anthropologists are now relying on the results produced. Written by one of the foremost experts on optical dating, this book aims to bring together in a coherent whole the various strands of research that are ongoing in the area. It gives beginners an introduction to the technique as well as acting as a valuable source of up to date references. The text is divided into three parts; main text, technical notes and appendices. In this way the main text is accessible by those researchers with a limited knowledge of physics, with the technical notes providing depth of understanding for those who require it. The first part of the book is concerned with basic notions and an introduction to the standard techniques, as well as several illustrative case histories. It goes on to then discuss the limitations of the technique and factors affecting reliability.
The migrants and their communities
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E
Published: November 2023

The Tokelau District Officer in Apia, Western Samoa, noted in June 1963 that 54 Tokelauans had departed from Apia for New Zealand since the previous January. Fourteen of these had been sponsored in some way, but the other forty had gone independently, following Tokelauans who had migrated to New Zealand during the four previous years. Unsponsored migrants preceded those who were sponsored, and certainly have consistently outnumbered them. However, simply to dichotomize migrants as unsponsored or sponsored masks differences within each category and overlooks similarities between the two. A more refined classification is required, taking into account patterns of migration which changed over time. Before describing the history of Tokelauan migration, however, one must deal with issues of definition. Who is a Tokelauan migrant?
Health problems of Polynesians: a historical perspective
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E
Published: November 2023

I have heard it mentioned in New Zealand that one of the greatest misfortunes which can occur to the inhabitants of an unknown island in the Southern Ocean, is its discovery by some civilised navigator. This painful reflection entirely refers to the misery the people suffer from the introduction of bad habits and new diseases’ (Thomson 1854).
Health behaviour and health services in Tokelau and New Zealand
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E
Published: November 2023

The influence of traditional or folk medicine on health behaviour and beliefs varies considerably in different areas of Polynesia and the South Pacific (Parsons 1985). The Tokelau Study’s anthropologists report that Tokelauans have neither an extensive range of healing agents and drugs nor a large number of recognized curers. None the less, folk medicine does play some part in the health behaviour of Tokelauans, both on the atolls and in New Zealand.
Migration and chronic diseases
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E
Published: November 2023

How does migration affect the incidence of chronic diseases? Can generalizations be made-even for one population moving to one new homeland, at one time in history? The experience of migration may differ greatly among individuals from the same population: for some it represents a traumatic uprooting and major culture shock, for some it may be a great adventure, for others it may mean little more than a change in the geographical setting of familiar activities and social networks. And some persons are more fortunate than others in their ability to adapt to change. However, it may be postulated that in so far as migration involves major changes in environmentin climate, in exposure to disease agents, in life-style, and in access to social supportchanges in health status are likely to occur. Thus, for Tokelauans, whose migration to New Zealand involved major changes in all these factors, the study expected to find significant differences between the health status of migrants and that of non-migrants. Following the logic of the ‘Western diseases’ theory, later summarized by Trowell and Burkitt (1981), we expected that the incidence of chronic diseases in particular would be higher in the migrant group. This chapter will investigate this hypothesis as it relates to coronary heart disease, diabetes, gout, osteoarthritis, asthma, and respiratory diseases related to smoking (for example chronic bronchitis).
Efferent organization of the mammalian basal forebrain
Authors: Koliatsos V E , Martin, L J , Price D L
Published: November 2023

The basal forebrain includes heterogeneous groups of neurons located in ventral and medial aspects of the tele- and diencephalon that are not clear components of other major forebrain structures, such as basal ganglia, hypothalamus, or cortex. Recently, this area of brain has become a focus of research, due in part to discoveries that specific populations of basal forebrain neurons participate in learning and memory (Bartus et al. 1986; Olton and Wenk 1987) and degenerate in certain types of dementias, including Alzheimer’s disease (AD) (Whitehouse et al. 1981; Price et al. 1985), Down’s syndrome (Casanova et al. 1985), progressive supranuclear palsy (Tagliavini et al. 1984; Rogers et al. 1985), and some cases of Parkinson’s disease (Arendt et al. 1983; Whitehouse et al. 1983). In this chapter, our primary goal is to discuss the current understanding of the efferent organization of basal forebrain nuclei that contain cholinergic neurons. We also summarize the organization and projections of basal forebrain areas topographically related to the cholinergic nuclei, with the understanding that this summary further clarifies the circuitry of cholinergic neurons.
Cholinergic neurotransmission in the brainstem: Implications for behavioural state control
Authors: Greene R W , Mccarley R W
Published: November 2023

Numerous recent studies have suggested an important role for brainstem cholinergic transmission in the control of mammalian behavioural state (Hu et al. 1989a, b; Greene et al. 1989). One of the most striking demonstrations of importance has been the production of REM sleep by microinjection of cholinergic compounds (both agonists and cholinesterase inhibitors) into specific locations within the medial pontine reticular formation (mPRF; George et al. 1964; Amatruda et al. 1975; Baghdoyan et al. 1985). Applied at the proper injection site, cholinergic agonists elicit a complete array of REM phenomena including muscle atonia (as in natural REM, the alpha motoneurons are hyperpolarized), EEG desynchronization, ponto-geniculooccipital (PGO) waves, rapid eye movements and hippocampal theta rhythm, providing the only phenomenologically adequate model of REM sleep.
Dysdifferentiation of structurally plastic neurons initiates the pathologic cascade of Alzheimer’s disease: Toward a unifying hypothesis
Authors: Woolf N J , Butcher L L
Published: November 2023

The fundamental neuropathologic processes underlying Alzheimer’s disease, a term used in this book to refer to both presenile and senile dementia, are incompletely understood, despite increasingly intense research efforts aimed at unravelling the many threads comprising the total fabric of the disorder. Here we attempt to develop a unifying conception of Alzheimer’s disease based on the thesis that the trigger for the disorder is dysdifferentiation of neurons capable of oscillating between more plastic and more stable states in the mature central nervous system, which leads to the synthesis of altered cytoskeletal proteins that, in turn, initiate a cascade of interlocking pathologies characterized by nerve terminal aberrancies, subsequent extrusion of atypical polypeptide entities, reactive gliosis, abnormal neuronal growth, and degeneration.
Eye-head co-ordination: influence of eye position on the control of head movement amplitude
Authors: Delreux Vincent , Abeele Sylvie Vanden , Lefevre Philippe , Roucoux AndrÉ
Published: November 2023

Orienting the gaze towards a visual stimulus is usually by a combined eye and head movement. How the position of the target in space is transmitted to the motor systems of the eye and head is still a matter of debate. Among the unsolved questions, the nature of the frame of reference into which motor commands sent to the neck muscles are coded is particularly intriguing. Common sense suggests that the retinal error (the position of the target on the retina, i.e. a signal coded within a retinocentric frame of reference) should not be sent as such to the motor plant of the head. This error should at least take into account eye position in the orbit (craniocentric coding) and perhaps head position with respect to the trunk
Spatial programming of eye movements
Authors: Schlag John , Schlag-Rey Madeleine , Dassonville Paul
Published: November 2023

To direct gaze on a visual target, the simplest solution for the brain would be to derive the vector of the appropriate saccade directly from the retinal error signal generated by the target. This signal represents a distance and a direction from the centre of the fovea, and can be directly provided by the retinal cells ‘seeing’ a single point on a blank background. There are good reasons, however, to doubt that a scheme relying solely on a retinal error signal is realistic. It does not explain how, in the dark, one can look successively at two sites between which a photic target has jumped, remaining at each place for a very short time (double-step paradigm). Human subjects can do this accurately even though the target is no longer visible when the two eye movements are actually executed (Hallett and Lightstone 1976). As the trajectory from the first to the second location does not start at the initial point from which the target has been seen, the vector of the second saccade cannot be equal to the retinal error. The calculation of the vector for the second saccade by the brain must take into account the change in eye position.
Space and the parietal association areas
Authors: Stein J F
Published: November 2023

In this chapter I will attempt to evaluate the evidence that the main function of the posterior parietal association area is to begin the transformation of sensory input into signals of use for controlling movement by mediating the accurate, spatial direction of attention. To do this I will show that the association areas behind the primary somaesthetic cortical areas 1, 2, and 3, which are collectively known as the posterior parietal cortex (PPC), are not merely passive association areas in which different sensory inputs are integrated; rather, that first and foremost they are sensorimotor association areas, where sensory, motor, and motivational inputs are brought together so that they can be correctly interpreted in the light of how the animal is moving. Sensory and motor signals about the position and movements of our bodies and of surrounding objects of interest are evaluated in the PPC by neural networks that enable us to direct our attention to them and then to shift our gaze to look at or move towards them.
Congruent representations of visual and somatosensory space in single neurons of monkey ventral intra-parietal cortex (area VIP)
Authors: Duhamel Jean-Ren É , Colby Caroll. , Goldberg Michael E
Published: November 2023

We perceive the space in which we live by the use of all of our senses. Vision is the pre-eminent sense in primates, but we can also use audition, somatic sensation, and even olfaction. Our perception of space is calibrated by the accuracy of our movements through it. This calibration requires an intermodality equivalence, such that stimuli of disparate modalities ultimately evoke equivalent responses at some place in the nervous system. Clinical and experimental evidence has long implicated the posterior parietal cortex in the process by which the brain constructs an image of space (Critchley 1953). The posterior parietal cortex lies at the junction of visual and somatosensory cortices, and although historically it was thought to be a somatosensory association cortex, recent work has emphasized its visual nature (Hyvarinen and Poranen 1974; Lynch et al. 1977; Robinson et al. 1978). Such studies also demonstrated some convergence between vision and somatic sensation in the posterior parietal cortex of the monkey (Robinson et al. 1978; Leinonen et al. 1979).
Starvation and predation in a patchy environment
Authors: McNamara J M , Houston A I
Published: November 2023

Outside the breeding season, an animal's reproductive success will depend on its ability to survive. For many animals, survival involves finding enough food and avoiding being killed by a predator. It is, therefore, not surprising that considerable theoretical and empirical work has been done on the influence of the dangers of starvation and predation (see Real and Cameo 1986; Cameo and Lima 1987; Milinski 1986; Dill 1987 for reviews). In the absence of predation, the probability of starvation depends not only on the mean rate at which an animal obtains food, but also on the variance (Cameo 1980; Houston and McNamara 1982, 1985; McNamara and Houston 1982, 1986). The choices of juncos and white-crowned sparrows depend on variance and can be understood in terms of minimizing the animal's probability of starvation (Cameo 1981a, 1983; Cameo et al. 1980; review in Cameo and Lima 1987). Similar remarks apply to the foraging behaviour of the common shrew (Barnard and Brown 1985; Barnard et al. 1985).
Dynamic stability of a single-species population in a divided and ephemeral environment
Authors: Rosewell J P
Published: November 2023

Ecologists have become accustomed to the idea that even very simple models describing single-species populations may show oscillatory or irregular, chaotic population fluctuations in the absence of any extrinsic factors.
Variance and patchiness in rates of population change: a planthopper’s case history
Authors: Strong D R , Antolin M F , Rathbun S
Published: November 2023

Working out the ‘details’ is the business of experimental population dynamics, which has not recently played a major role in ecology. Experiments concerning the mechanisms of population change among generations have been few relative to the volume of theory on population dynamics; the vital feedback between theory and experimentation is not as well-developed in population dynamics as in other disciplines. This imbalance between experimentation and theory can be seen, perhaps, as an adequate gross volume of theory with a deficiency of experimentation (although we would certainly like to see more theory inspired by realistic assumptions) (Strong 1986a, b).
Population dynamics and community structure of parasite helminths
Authors: Dobson A P , Keymer A E
Published: November 2023

Although definitions of parasitism may be very broad (Price 1980), we restrict this chapter to a discussion of helminth parasites: the platyhelminthes, nematodes and acanthocephalans. The population dynamics of these macro-parasites (Anderson and May 1979) are characterized by aggregated distributions in the host population and the dependence of parasite fecundity and pathogenicity upon the numbers of parasites harboured by the host. This contrasts with the micro-parasites which reproduce within the host and may be regarded to subdivide the host population into a few distinct classes (susceptible, infected but latent, infectious, recovered, and immune). Comprehensive discussions of the population dynamics of micro-parasites (which include viruses, bacteria, and protozoa) have been given by Anderson and May (1981, 1982).
Case study: scaling behaviour of density-dependent populations under random noise
Authors: Hastings Harold M
Published: November 2023

11.1 Introduction

The prediction of local species extinction is a useful goal and test for population models. Essentially by definition, the population levels of a species which persists for a long time remain within a bounded range, and thus there is an asymptotic value to the range of population fluctuations. The challenge is therefore to predict the long-term range of population values from available time series which are frequently relatively short.
Coevolution of Macroparasites and their hosts
Authors: Dobson Andrew P , Merenlender Adina
Published: November 2023

The coevolution of microparasites (viruses, bacteria, and protozoa) and their hosts has received extensive theoretical and empirical attention (Anderson and May 1983; Bremmermann and Pickering 1983; May and Anderson 1984; Toft and Karter 1990; Dwyer et al. in press). In contrast, there have been few attempts to synthesize the available data for the coevolution of macroparasites (parasitic helminths and arthropods) and their hosts. This review will describe some simple models for the coevolution of macroparasites and their hosts and attempt to synthesize some of the existing data on the ecology and genetics of these interactions.
A physiological perspective: physiological adaptations in host parasite systems
Authors: Castro Gilbert A
Published: November 2023

Adaptation is a word with many connotations (Prosser and Brown 1961; Fairbairn 1970), but, in general, refers to the fitness of an organism for its environment (Gould 1982; Keymer and Read, Chapter 3; Dobson and Merenlender, Chapter 5; May, Chapter 6; Harvey et al., Chapter 17, this volume). Physiologists view ‘adaptation’ as the process of adjustment by an organism to a changing environment. This view includes adjustments that occur within the life of an individual, and therefore represents acclimation or acclimatization, i.e. adjustments to single or multiple environmental factors, respectively, that contribute to homeostasis (Prosser and Brown 1961). However, because coping with environmental changes enhances survival and reproductive capacity in the long term, physiological adaptations relate to ‘adaptations’ in the evolutionary sense (Dobzhansky 1951). This holds true for both parasites and their hosts.
Neurophysiological analysis of striatal function
Authors: Rolls Edmund T , Johnstone Syren
Published: November 2023

The striatum receives inputs from different areas of the cerebral cortex, including association cortical areas far on in the hierarchy of cortical information processing as well as the sensori-motor cortex, and has connections via the globus pallidus and substantia nigra to the thalamus and thence to premotor and prefrontal cortical areas. Recordings of the activity of neurons in different parts of the striatum of primates show that they have the following properties:
Thalamic and non-thalamic subcortical aphasia: a neurolinguistic and SPECT approach
Authors: Démonet J F , Celsis P , Puel M , Cardebat D , Marc-Vergnes J P , Rascol A
Published: November 2023

In the current literature, so-called subcortical aphasia frequently refers to aphasic syndromes associated with subcortical non-thalamic lesions involving the lenticular nucleus, the caudate nucleus, and the internal capsule. Nevertheless, aphasia associated with thalamic lesions does exist. In 1987, we reviewed 251 reported cases of linguistic disorders associated with vascular subcortical lesions (Table 18.1): we found 108 thalamic cases and 143 non-thalamic cases (Demonet 1987). Language disorders were typified as classic aphasia in 6 per cent of thalamic cases and in 36 per cent of nonthalamic cases.
Role of subcortical structures in aphasia: evidence from studies of resting cerebral glucose metabolism
Authors: Metter E Jeffrey
Published: November 2023

Recent work has demonstrated the presence of aphasia with subcortical structural lesions including caudate, putamen, thalamus, and internal capsule. Divac and Öberg (Chapter 2, this volume) and Crosson (Chapter 12, this volume) have argued that the role of subcortical structures, and in particular the striatum and thalamus, is to act as part of a corticalsubcortical feedback loop which modulates, in a tonic manner, cortical function. Feedback loops are known to involve the frontal cortex, and the temporo-parietal cortex. Divac and Öberg argue for a multiple-tier organization of the forebrain with horizontal integration within a tier and vertical systems between the tiers. A vertical system consists of cortical-subcortical loops, that are focused around a specific thalamic nucleus. The basal ganglia are an integral part of some vertical systems. Divac and Öberg believe that the vertical systems mediate many types of complex behaviours. Language may be an exception by not being directly associated with the striatum. Crosson argues more specifically for cortico-striatal-thalamic loops, noting the existence of both anterior and posterior loops. He believes that these loops have a direct role in language. A critical question becomes whether it is disruption of these feedback systems that is important in subcortical aphasia, or whether (or to what extent) it is the intrinsic characteristics of the subcortical structures themselves that may play a role in the language abnormality.
Models, modules, and molecules in morphogenesis
Authors: Blackmore Stephen
Published: November 2023

This paper explores the relationships between ontogeny and phylogeny by focusing on the nature of development and the ways in which it has been conceptualized.
Inferring evolutionary processes from molecular phylogenies
Authors: Harvey Paul H , Holmes Eddie C , Mooers Arne Ø , Nee Sean
Published: November 2023

Phylogenetic trees are usually constructed in which extinct lineages are either under-represented or absent. Fossil-free trees, such as many molecular phylogenies, contain information about the evolutionary processes that gave rise to them. A variety of processes, including mass extinctions and density dependent lineage death rate, leave their own identifying signatures on such trees. Reconstructed avian and viral phylogenies can be used to reject some models of evolution but not others.
Population and the environment: complex interrelationships
Authors: Clarke John
Published: November 2023

Professor John Clarke DL is Emeritus Professor of Geography at the University of Durham. He took his first degree and was awarded his doctorate at the University of Aberdeen, where he was appointed an Assistant Lecturer in geography in 1954. He moved to Durham a year later to take up the lectureship which he held there until 1963. He then spent 2 years in West Africa, as Professor of Geography at the University College of Sierra Leone, before returning to Durham as Reader and, from 1968, Professor of Geography-a post that he held for 22 years. Professor Clarke served as Pro-Vice-Chancellor and Sub-Warden of the university from 1984 until his retirement in 1990, when he became a Deputy Lieutenant of County Durham. He is a vice-president of the Royal Geographical Society, Chairman of the Population and Environment Committee of the International Union for the Scientific Study of Population (IUSSP), a former chairman of the International Geographical Union’s (IGU) Commission on Population Geography, and the author and editor of many books on population geography, especially with reference to the developing countries. Professor Clarke is also Chairman of the North Durham Health Authority.
The potential effects of climate change on world food supply
Authors: Parry Martin
Published: November 2023

After graduating at the University of Durham and taking a Master’s degree at the University of the West Indies, Professor Parry was awarded his doctorate at the University of Edinburgh in 1973 for research in geography. In the same year he was appointed to a lectureship in geography at the University of Birmingham, where he subsequently held the appointments of Senior Lecturer, Reader in Resource Management and, from 1989, Professor of Environmental Management. In 1991, Martin Parry was appointed to be the first IBM Director of the newly established Environmental Change Unit in the University of Oxford and became a Professorial Fellow of Linacre College. He has held a number of visiting appointments overseas, including that of Director of the Climate Impacts Project at the International Institute for Applied Systems Analysis in Austria. In 1993 Professor Parry was a joint winner of the Norbert Gerbier-Mumm International Award for work in applied meteorology. He left Oxford in 1994 in order to take up the post of Professor of Environmental Management and Director of Environmental Studies at University College, London.
Introduction to Petroleum Exploration For Non-Geologists
Authors: Stoneley Robert
Published: November 2023

Over 1000 people have attended the three-day course on which this book is based since it was instituted in 1981 by JAPEC (Joint Association for Petroleum Exploration Courses). Key topics covered in this book are: the underlaying rationale for exploration; essential basic geological and geophysical exploration techniques; drilling and logging wells; an outline of reservoir geology and what constitutes reserves; and all of these topics are brought together in a case-history overview of exploration in the North Sea. The book is fully self-explanatory, needs no prior knowledge of geology or of exploration techniques, and as much as possible avoids the use of technical jargon. There is, however, a lengthy glossary of technical terms that can be used as a reference. The appeal of the book extends far beyond the audience originally envisaged for the JAPEC course. Anyone interested in finding out what petroleum exploration is all about will enjoy this volume.
North Sea case history
Authors: Stoneley Robert
Published: November 2023

At the beginning of the I 960s virtually nothing was known about the geology of the North Sea. In 30 years it has become a well explored and prolific oil producing region, and the geology is known in considerable detail. This is a remarkable success story of exploration, technological development, and of cooperation between the petroleum industry and national governments. Despite a few sad accidents, it has been achieved with relative safety under extremely hazardous conditions, and with very little effect on the environment. Let us look at the story in the light of what has been covered in this book.