bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metapopulation dynamics and conservation biology
Authors: Hanski llkka 
Published: November 2023

Abstract
Conservation biology evolved into a distinct field of biology in the 1970s, with two major contributions from population biology, the dynamic theory of island biogeography (MacArthur and Wilson 1963, 1967) and population genetics applied to endangered species, particularly in the study of drift and inbreeding in small populations (Simberloff 1988). The island biogeographic theory quickly attracted much attention (Fig. 10.1). In this theory, species number on true and habitat islands settles to a dynamic equilibrium between ongoing local extinctions and recolonizations. The island theory clearly shares key underpinnings with metapopulation models-the division of nature into discrete fragments of habitat, with movement of individuals among relatively unstable local populations.
Ontogeny of hunting behaviour of otters (Lutra lutra L.) in a marine environment
Authors: Watt Jon 
Published: November 2023

Abstract
The foraging activity of 15 individually recognizable otters was recorded along the coast of Mull between July 1987 and November 1989. Data were gathered on the success rates of dives, size and identity of prey captured, dive duration and duration of pauses between dives. Cubs (n = 5) began to capture a small proportion of their own food by five months of age and this proportion increased with age. The rest of the cubs’ food was provided by the mother. By 13 months of age all cubs were self sufficient foragers. The diving success and weight of prey captured per hour of foraging increased with age and continued to improve after the attainment of independence.
Hunting success of lions in a semi-arid environment
Authors: Stander P E , Albon S D 
Published: November 2023

Abstract
Parameters that influence the hunting success of lions in a semi-arid region in Namibia were assessed by means of generalized linear models. Results indicate that when combined, hunting techniques employed by lionesses, lioness group size, prey species, time of day (day/night), terrain, and the interaction between terrain and day/ night had significant independent effects on the probability that a hunt would be successful. Hunts that involved co-ordinated stalking were more likely to succeed than other hunt categories. Success of hunting the five major prey species increased linearly with lioness group size. Lionesses were also more successful during hunts on moonless nights in undulating terrain. Under the semi-arid conditions in Namibia, where lions are exposed to eight months of food scarcity in an open habitat, group hunting and co-ordinated co-operation are the most important variables influencing the outcome of hunts and therefore also per capita food intake. In this environment group hunting may be an important factor in the evolution of sociality in the species.
Seasonal dispersion and habitat use of foraging northern elephant seals
Authors: Stewart Brent S , Delong Robert L 
Published: November 2023

Abstract
Elephant seals are at sea and dive continously for 8-10 months each year. They range widely in the North Pacific; their dispersion and migratory patterns correspond with three major North Pacific oceanographic features where enhanced biological productivity supports deep-water assemblages of elephant seals’ primary cephalopod prey. Throughout the year adult males are dispersed farther north than females. Both sexes forage primarily on squid that reduce their specific gravity to maintain neutral buoyancy either by storing fat in their bodies or by actively replacing heavy metal ions in their body fluids with lighter ammonium ions. Squid with these adaptations are slower swimmers, and therefore probably more susceptible to predation by elephant seals, but are of poorer nutritional quality than are negatively buoyant squid species. Adult elephant seal males may gain access to higher-quality prey than females by travelling farther north to capitalize on larger fat-rich gonatid squid, the dominant cephalopod fauna in the Subarctic water mass. It is not clear why females do not forage in those northern areas. But reduced intraspecific competition for food resources because of such sexual segregation of foraging adults has important implications for demographic studies of the rapidly growing northern elephant seal population.
Role of plasma and tissue lipids in the energy metabolism of the harbour seal
Authors: Davis R W , Beltz W F , Peralta F , Witztum J L 
Published: November 2023

Abstract
Lipid is an important source of energy for harbour seals and other carnivorous marine mammals. This results primarily from their diet, which is rich in fish oil, and the large lipid stores in the blubber. Measurements of respiratory quotient (RQ) indicate that whole-body lipid catabolism provides 87% of metabolic energy for resting and 95% for exercising harbour seals. In earlier studies, we showed that the catabolism of plasma free fatty acids (FFA) provides only about 20% of total energy production in harbour seals. Recent studies indicate that very low density lipoprotein triglycerides (VLDL-TG) may provide an additional 13% of energy production in postabsorptive harbour seals. However, the catabolism of fatty acids from triglyceride-rich chylomicrons may increase fourfold after a meal and represent the primary source of lipid for energy metabolism during foraging dives. The third source of lipids is endogenous triglyceride stores in the tissues, especially skeletal muscle. Although studies to quantify the catabolism of endogenous tissue triglycerides are just beginning, the prospect of assembling a complete fuel budget for resting and exercising harbour seals appears good. This information will contribute to our understanding of how marine mammals partition oxygen and fuel reserves to maintain an aerobic, fat-based metabolism during most voluntary dives.
Balancing power and speed in bottlenose dolphins (Tursiops truncatus)
Authors: Williams T M , Friedl W A , Haun J E , Chun N K 
Published: November 2023

Abstract
Hydrodynamic, energetic and physiological limitations dictate the swimming speed and duration of submergence of marine mammals. To determine the effects of these limitations on swimming and diving performance by cetaceans, we examined the relationships among aerobic transport costs, oxygen stores and locomotor speed of bottlenose dolphins. Metabolic rate and the cost of transport were assessed for two adult dolphins trained to swim next to a boat.
Some applications
Authors: Aitken M J 
Published: November 2023

Abstract
The brief outlines given in this chapter have the objective of illustrating the way in which practical application has been made of the techniques and principles of the preceding chapters; it is not a comprehensive review. These examples also serve to indicate the wide range of sediment types for which optical dating can be used; this range includes: dune sand, loess, colluvial sediment, sand aprons formed from disintegrated sandstone, organic-rich sediment, buried podsols, and even the mud of wasps’ nests.
The history of Tokelau: 1841 to 1948
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E 
Published: November 2023

Abstract
By the end of the eighteenth century, following some two hundred years of exploration by Portuguese, Spanish, Dutch, French, and British navigators, virtually all the islands of the Pacific were known to the European world. From then on, the islands began to feel the weight of European ambitions - for souls, commercial opportunities, and colonies -which inexorably drew them all, even the most remote, into the meshes of the expanding world system. In the South Pacific, it was mainly Christian missionaries who made the first direct incursions into the island societies. Everywhere, though, they were quickly followed by traders seeking sandalwood, beche—de-mer, or labour, and by the whalers of both Europe and the United States who sought safe harbours for replenishment of their supplies and for whatever other refreshments might be available.
Social characteristics of the migrant communities
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E 
Published: November 2023

Abstract
This chapter is largely based on census data. Sources include the study team’s 1977 and 1985 Project Censuses of all New Zealand Tokelauans, the New Zealand Censuses of 1976, 1981, and 1986, and information from our medical examinations and sociological interviews in New Zealand. These data not only provide a sketch of the living conditions of the migrants, but they also indicate some of the distinguishing features of each of the several migrant communities and their changing character.
Migration and blood pressure
Authors: Wessen Albert F , Hooper Antony , Huntsman Judith , Prior Ian A M , Salmond Clare E 
Published: November 2023

Abstract
The major epidemiological goal of the Tokelau Island Migrant Study was to document the influence of migration on the development of ‘Western diseases’ within a population in which incidence of such diseases had been low before resettlement in a modern urban social milieu. As was explained earlier, Tokelauans in the late 1960s seemed to constitute an ideal population for this effort. As noted in Chapter 8, however, the population of Tokelau is young-a characteristic of developing societies where birth rates are high. Since many of the diseases associated with modern urban living are chronic and affect older people primarily, and therefore are uncommon in a young population, blood pressure was selected as a useful, easily-monitored indicator by which to assess physiological changes associated with migration.
Parallel activation of thalamic and cortical neurons by brainstem and basal forebrain cholinergic systems
Authors: Steriade M , Buzsaki G 
Published: November 2023

Abstract
As commonly happens in the history of science, ideas about neuronal substrates of behavioural activation have evolved from the concept of a globally-energizing monolithic structure to its dissection into distinct nuclear divisions and functional systems. The first demonstration that the brainstem is the key structure in maintaining the electrical activity of the cerebrum related to the vigil state was carried out by Bremer (1935, 1937) who showed that an animal with a bulbospinal transection (the encephale isole preparation) alternates between sleep and wakefulness, as indicated by electroencephalogram (EEG) and ocular behaviour, whereas a midbrain-transected (cerveauisole) preparation is comatose. Moruzzi and Magoun’s (1949) experiments led to a distinction between the brainstem reticular core which was thought to be essential for EEG activation and classical sensory pathways that were considered nonessential. In those acute experiments the basic sign of brain activation was the replacement of spontaneous high-amplitude synchronized EEG waves by low-amplitude fast (desynchronized) activity, without evidence of increased cerebral responsiveness during the EEG-desynchronized state. Actual demonstration of enhanced cortical response under brainstem reticular stimulation came a decade later by means of field potential recordings (Bremer and Stoupel 1959; Dumont and Dell 1960). We define in § 1.2 the notion of activation and we discuss the full methodological armamentarium that should be used to assess it.
The nucleus basalis of Meynert during ageing and in dementing neuropsychiatric disorders
Authors: Bigl V , Arendt’ T , Biesold D 
Published: November 2023

Abstract
When Lewy (1913) described for the first time the severe degeneration of neurons in the nucleus basalis of Meynert (NBM), at that time termed nucleus of the Substantia Innominata, in cases with paralysis agitans, this marked the beginning of a long development which finally shifted this comparatively small brain structure into the focus of modern neurobiological research. At the time of Lewy’s discovery the function of the NBM and its fibre connections were unknown. On the basis of histological evaluation, Lewy attributed the neurons of the NBM to the motor type. Hassler (1938) confirmed and extended Lewy’s findings, and in 1965 he was the first to deduce the significance of the NBM for cognitive rather than motor function. Hassler (1965) stated: ‘because these nerve cells of the basal nucleus have no relations to motor functions, their loss is supposed to be related to the most frequent psychical alteration in paralysis agitans, which is called bradyphrenia. This is characterized by a slowing down of thinking, a delay and reduction of emotional reactions, a failure of distributive attention and difficulty of decision’.
Kew Index For 1989
Authors: Davies R A , Lloyd K M 
Published: November 2023

Abstract
This is the fourth of a series of annual supplements to the Index Kewensis. It will provide more up-to-date information than has hitherto been available for the five-yearly supplements that have been issued since the appearance of the original work in 1895. As in the five-yearly supplements, information is included on new and changed names of seed-bearing plants at the level of family and below. There is an additional section listing new and overlooked generic names. In this volume there are no entries for ferns at the ranks above genus.
Kew Index For 1989 Names of all ranks above genus Up To And Including Family
Authors: Davies R A , Lloyd K M 
Published: November 2023

Abstract
COMMELINACEAE subfam. Cartonematoideae (Pichon) R. Faden ex G.C. Tucker in J. Arnold Arbor., 70( 1): 99 (1989): Cartonemataceae. COMPOSITAE tribus Plucheae A.A. Anderberg in Canad. J. Bot., 67(8): 2293 (1989), as '(Benth.)'.
Sensorimotor space representation: a Neuromimetic model
Authors: Gilhodes Jean-Claude , Coiton Yves , Velay Jean-Luc 
Published: November 2023

Abstract
Superior vertebrates, particularly humans, exhibit a great range of motor behaviours, among which spatially oriented activities are fundamental. Activities directed in space require at least the presence of a sensory signal coming from the immediate environment. In principle, this signal should suffice to trigger a correct motor response, assuming that there exists a precabled link between this input and a given motor response. This simple mechanism involves only a primary level of spatial perception and does not necessitate an internal model of space. A great number of primitive animals probably act on the basis of primary mechanisms of this type. Their motor behaviour is fairly restricted, however, and in addition there is no possibility of adaptation to environmental changes. In fact, in the majority of superior organisms, the sensorimotor relationship is not completely fixed but can be modified in the course of life, if necessary. Furthermore, the relationship is not given at birth but has to be learned early in life. Highly evolved nervous systems must therefore build and store an internal sensorimotor representation in which motor responses are interconnected with sensory signals.
Dung and carrion insects
Authors: Hanski I 
Published: November 2023

Abstract
Dung and carrion are the textbook examples of patchy and ephemeral resources. In reality, they range many orders of magnitude in habitat patch size and durational stability, as well as in their density in the surrounding environment. African savannas in the rainy season present one end of the continuum (Kingston 1977). Innumerable dung pats, marking the trails of herds of large herbivores, are hot spots of beetle life: Anderson and Coe (1974) counted 16000 dung beetles arriving at a 1.5 kg heap of elephant dung in East Africa. Working in West African savannas, Cambefort (1984) estimated that beetles bury 1 metric tonne of dung per hectare per year. Locating the resource may not be a great problem in the savanna ecosystem, but competition is: the above elephant pat was eaten, buried and rolled away in 2 hours.
Patchiness and community structure
Authors: Kitching R L , Beaver R A 
Published: November 2023

Abstract
An ecological community is a set of organisms usually associated with a particular habitat and connected by first, second, or higher order interactions in time and/or space. Implicit in this definition is the idea of a degree of coevolution among the organisms involved and a repeatability in constitution and structure through time. As such we often make the perhaps unjustified assumption that these entities, communities, transcend the environmental patchiness, a consideration of which is crucial in any proper treatment of the ecology of single species, as other chapters in this book testify. Of course, communities are made up of populations of animals and plants, the dynamics of each of which reflect behaviour evolved to cope with heterogeneity in the environment of individuals of that particular species. We show in this chapter, however, that there are community-level responses to patchiness, expressed as variation in habitat quality in both space and time and that these may be apparent on both local and geographical scales. The difficulties in such an analysis and the probable reason why such community-level considerations of patchiness and its role in ecosystems have received relatively little attention, are twofold. First we must choose appropriate parameters which reflect community responses to patchiness and, perhaps, more serious, we must find real-world examples in which to measure these responses.
Our view of nature
Authors: Hastings Harold M 
Published: November 2023

Abstract
Natural patterns, especially those in ecosystems, frequently appear irregular, complex, and hard to measure, even at very small scales. Consider, for example, the problem of measuring the length of the coastline of England (Richardson 1961; cf. Mandelbrot 1977, 1982). Richardson attacked this question by traversing the coastline in a sequence of small steps, and counting the number of steps required. If the coastline could be traversed in n(Δ s) steps, each of length Δs, then the product n(Δ s) Δs would be a close approximation of the actual length. If the coastline were a smooth curve, then for very small steps the apparent length n(Δ) Δ s would closely approximate the actual length, implying that
n(Δ s) = const x (1/ Δ s).
Fractals and power law scaling
Authors: Hastings Harold M 
Published: November 2023

Abstract
The examples from Chapter 1 demonstrated that some natural patterns can appear extremely complex. However, they may display an underlying simplicity through scale-invariance. Again, scale-invariance means that the pattern appears unchanged under magnification or contraction. More generally, there may be several scaling regions, separated by breakpoints, with scale-invariance holding within each region, but failing when a break-point is crossed.
Dimension of patterns
Authors: Hastings Harold M 
Published: November 2023

Abstract
In the last chapter we introduced two related concepts of dimension for fractals: the scaling dimension (Section 2.3) and the Hausdorff dimension (Section 2.5). We then described the axioms for fractal processes, whose graphs form prototype random fractals (Section 2.4), and power laws, the fundamental algebraic property that links dimension and self-similarity (Section 2.6). We shall now develop alternative equivalent definitions of dimension, with practical methods for computing the dimension of random fractals, in particular, the graph of Brownian motion. We shall also develop some additional properties of dimension.
Examples
Authors: Hastings Harold M 
Published: November 2023

Abstract
In this chapter we introduce the application of fractals to the study of spatial patterns through several illustrative examples: the work of Hastings and Troyan (1991) on scaling in earthquake time series (Section 8.2), the work of Hastings et al. (1992) on pancreatic islets (Section 8.3), and the work of Caserta et al. (1990) on neuronal processes (Section 8.4). The following section considers the possibility or impossibility of predicting earthquakes, and asks about possible measurable differences between earthquakes along fault lines and ‘mid-continent’ earthquakes far from fault lines. Which comes first-the fault or the earthquake? The last two sections investigate a possible universal role for diffusion-limited aggregation in developmental biology (Witten and Sander 1981; Meakin and Tolman 1989), as suggested by Caserta et al. (1990), Kleinfeld et al. (1990), and Hastings et al. (1992).
Fractal analysis of time series
Authors: Hastings Harold M 
Published: November 2023

Abstract
We begin by reviewing the process of’detrending’, using to eliminate large cyclic trends (such as those in temperature data) or linear trends, and considering when to form cumulative time series. We next illustrate these processes and fractal modelling by studying California ocean surface temperatures and New Jersey rainfall data. The chapter concludes with a brief formal comparison of fractals with residence time models. A detailed case study on the application of fractals to population dynamics and the possible application to forecasting species extinction (see Sugihara and May 1990a) is given in Chapter 11.
Immunological relationships between host and ixodid ticks
Authors: Brossard M , Rutti, B , Haug T 
Published: November 2023

Abstract
Ticks are important ectoparasites and vectors of diseases to humans and animals (Aeschlimann, Chapter 8, this volume). They cause substantial economic losses in livestock production all over the world (FAO 1983). Two tick families are parasitologically important: the Ixodidae (hard ticks) and the Argasidae (soft ticks) (for details of their life histories, see Chapter 8 by Aeschlimann, this volume). The immunological interactions between hosts and the economically more important ixodid ticks have been better investigated than in argasids (reviews by Willadsen 1980, 1987; Wikel and Allen 1982; Brown 1985, 1988a; Wikel and Whelen 1986; Ribeiro 1987; Kaufman 1989). Because of the relatively long feeding period, ixodid ticks particularly need to evade the host’s immune and inflammatory responses. The importance of this ability is illustrated by tick-host associations which have existed for a long time or which have been newly established (i.e. by the introduction of livestock). In long-established relationships one might expect that the coevolution of the host’s immune system and of the parasite’s immune-evasion system has led to some degree of adaptation.
Action of calcium ions on the surface of nerve cells
Authors: Kostyuk Platon G 
Published: November 2023

Abstract
Modern ideas about the mechanisms of interaction between calcium ions and the external surface of excitable cell membranes originate from the studies of Frankenhaeuser (1957) on frog nerve fibres and Frankenhaeuser and Hodgkin (1957) on squid giant axons. It was established in these experiments that an increase in the extracellular Ca2+ concentration greatly increases the threshold of action potential generation without changing the resting potential value. A similar alteration has been found in other excitable structures, for instance in cardiac muscle fibres (Weidman 1955).