bluuebunny/crossref_metadata_2025 huggingface dataset:
Habitats, feeding ecology, and home range size in the genus Callithrix
Authors: Rylands Anthony B , Faria Doris S de
Published: November 2023

The most recent taxonomic revisions of the marmoset genus Callithrix indicate more than 14 species and subspecies, distributed through the southern and eastern part of the Amazon basin (south of the Rio Amazonas and east of its southern tributary, the Rio Madeira) extending into eastern Bolivia and the northeastern tip of Paraguay (eight taxa), and throughout most of central, northeastern and southeastern Brazil (six taxa) (Mittermeier et al. 1988b; Ferrari and Lopes 1992b; Coimbra-Filho 1990; for review see Rylands et al. this volume). Although still lacking sufficient extensive field studies, the wide distribution of this genus testifies to the wide variety of habitats that marmosets occupy, and argues for significant ecological and behavioural differences between the various forms. In this paper, we review the current knowledge regarding their feeding and ranging behaviour with the aim of identifying key features which unite the genus and the differences which separate them, and which are related to their use of contrasting habitats. Aspects of their social behaviour have been reviewed by Sussman and Kinzey (1984), Sussman and Garber (1987), Stevenson and Rylands (1988), and Ferrari and Lopes Ferrari (1989) (see also Rothe and Darms, this volume).
Feeding ecology and behaviour of the genus Saguinus
Authors: Garber Paul A
Published: November 2023

Tamarins of the genus Saguinus represent a successful radiation of New World primates that exploit a wide range of primary, secondary, and forest edge habitats from western Panama throughout much of the Amazon Basin of Colombia, Ecuador, Peru, Bolivia, and northern Brazil (Hershkovitz 1977; Mittermeier and Coimbra-Filho 1981, Snowdon and Saini 1988). In terms of species number and subspecific differentiation, this genus is the largest and most diverse platyrrhine lineage with three primary groupings (hairy-face taxa, mottled-face taxa, and bare-face taxa), 11 species, and 29 recognized subspecies (Hershkovitz 1977; Mittermeier and Coimbra-Filho 1981; Mittermeier et al. 1988b) (Table 13.1). Although there is little fossil evidence from which to reconstruct the evolutionary history of this group, differentiation of many of the current species is likely to have occurred sometime during the Pleistocene (Hershkovitz 1977; Kinzey 1982; Ford 1986a).
Evolution, palaeobiogeography, and life history
Authors: Janvier Philippe
Published: November 2023

One step further from reality, we enter here the realm of evolutionary processes and life history, i.e. all the flesh that one may put on fossils, homologies, and phylogenetic patterns: whence, how, and why early vertebrates evolved, how they lived, on what they preyed, etc. These stories are often amusing, sometimes plausible, but generally untestable as theories. Some are long-lived, even if unlikely; others are bound to geological or biological fashions. Nevertheless, this book would be incomplete if it did not include stories of this kind relating to early vertebrates.
Priapulids, Sipunculans, Echiurans, and Entoprocts
Authors: Knight-Jones E W , Ryland J S
Published: November 2023

Unsegmented worms with a chitinous cuticle, small surface spines and papillae, a large body cavity, and near-radial symmetry, except for paired gonads and nephridia, and a nerve cord regarded as ventral. The anterior body forms an introvert, in which the mouth is central. This is alternately pushed out and withdrawn to burrow, and prey is drawn in and swallowed during withdrawal, having been caught by curved teeth on the everted mouth and pharynx lining. The gut is simple and the anus terminal, except that a few genera have long tails arising ventrally to the anus. These bear many vesicular branches, which contain extensions of the coelom and are thought to be respiratory. Sexes are separate and cleavage radial, producing loricate larvae which stay in the adult environment.
Parasitoids of leaf-mining Lepidoptera: what determines their host ranges?
Authors: Askew R R
Published: November 2023

Larvae of microlepidoptera which feed as leaf miners are heavily attacked by many species of parasitic Hymenoptera (Askew and Shaw 1974). These communities of parasitoid species are composed, with a few exceptions, of Chalcidoidea belonging to the family Eulophidae. The chalcid species vary in their biology in many ways. Some attack the leaf-mining caterpillars when these are in an early instar, but most do not do so until the larvae have finished or almost finished feeding, or have pupated. Most are primary parasitoids, but a number can behave as facultative hyperparasitoids through other Hymenoptera, and in a few species this is the principal mode of development. They may be solitary or gregarious, bisexual or thelytokous, ectophagous or endophagous, idiobionts or koinobionts (Askew and Shaw 1986). The most variable feature of parasitoid biology is, however, the host range. It is also the most difficult to define.
The window of parasitoid vulnerability to hyperparasitism: template for parasitoid complex structure
Authors: Stiling Peter , Rossi Anthony M
Published: November 2023

Tritrophic interactions can play an important role in determining the composition of parasitoid communities. In these interactions, the individual responses of each parasitoid in the community vary in accordance with intra and interspecific host-plant variation. In some cases, specific phytochemicals mediate the interaction between herbivores and their natural enemies (Barbosa 1988; Hare 1992). In others, physical attributes of the plant such as trichomes may affect parasitism rates by reducing the availability of hosts to searching parasitoids (Obrycki 1986). In gall-making insects, the thickness of the gall can determine which parasitoid species attacks which types of galls (Craig Chapter 11). In this chapter, we propose that tritrophic interactions can also affect parasitoid community structure by mediating interspecific competition between guild members.
Parasitoid communities, parasitoid guilds, and biological control
Authors: Ehler L E
Published: November 2023

In the native home of a given phytophagous insect species, we can expect to find several species of parasitoids characteristically associated with the particular insect at a given location. Such a cluster of species constitutes a ‘parasitoid community’, the members of which may either remain relatively constant or vary considerably in different parts of the host’s geographic range. Much of the recent literature on parasitoid communities is devoted to either comparative analysis of many different communities or more in-depth analysis of a single community. This chapter will emphasize the latter approach, with particular reference to interspecific interactions among species exploiting the same resource unit.
Metapopulation dynamics and conservation biology
Authors: Hanski llkka
Published: November 2023

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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).
Explanation, description, and the meaning of ‘transformation’ in taxonomic evidence
Authors: Brady R H
Published: November 2023

The nature of description and its role in scientific procedure is examined. Observation is theory laden, but not necessarily with explanatory theory. Darwin attempted, in the Origin, to absorb all the known facts of current morphology in his notion of homology. His insistence on literal ‘transformation’ between forms, however, forced a confusion between explanation and description that he did not notice. Recent papers have attacked the ‘transformation approach’, arguing that the hierarchy of forms is essentially static rather than successive. While this rejection of Darwin’s literalism appears correct, the emphasis on stasis may be misplaced. Pattern reconstruction must take logical precedence over process explanation, but topological relations can be dynamic without reference to succession. What I have termed ‘literalism’ understands the dynamic as the temporal, and this confusion between the realms of law and event continually leads to a substitution of explanation for description.
Three-item consensus: empirical test of fractional weighting
Authors: Nelson* G , Ladigest† P Y
Published: November 2023

Fractional weighting may be used in 3-item analysis in one or both of two procedures: obtaining one or more most parsimonious tree for character data, or obtaining a consensus among trees that represent different data. These procedures are applied to two published sets of molecular sequence data for mammals: five proteins, 128 informative sites (Cytochrome C, Fibrinopeptide A and B, Haemoglobin A and B), and 11 taxa (kangaroo, monkey, sheep, horse, mouse, rabbit, dog, pig, human, cow, ape); seven proteins, 186 informative sites (including Myoglobin and A-Crystallin), and 12 taxa (including cat). Results suggest that 3-item analysis with fractional weighting offers advantages over alternative methods.
Recent past and future extinctions in birds
Authors: Bibby Colin J
Published: November 2023

As a class, birds are second only to terrestrial molluscs in the number of known extinctions in the past few centuries (Jenkins 1992). If we understood extinction processes, we might be able to predict probabilities of future extinctions and target applied research and conservation work. Knowledge of recent past losses of species, either globally or locally, offers some understanding of extinction. Population modelling may give a more rigorous route to insight.
Estimating extinction from molecular phylogenies
Authors: Nee Sean , Holmes Edward C , May Robert M , Harvey Paul H
Published: November 2023

Increasing mechanization is turning a trickle of molecular information about phylogenies into a flood. Molecular phylogenies can both describe the hierarchical relationships among taxa by defining clades (monophyletic groups), and provide a time axis by utilizing molecular clocks. Even when those clocks have not been calibrated against real time, molecular phylogenies can still describe the temporal orderings of nodes relative to each other. We have shown elsewhere how many properties of the past, present, and even the future of a clade leave their footprints in its molecular phylogeny, even if that phylogeny is based only on information from extant organisms (Harvey et al. 1991, in press b; Nee et al. 1992). As a consequence, it is possible to use a careful combination of theoretical modelling, statistical analysis, and biological knowledge of the clade under investigation to make inferences about many aspects of the tempo and mode of its evolutionary history. In this chapter we describe how such inferences can be made, and produce illustrative examples to show how extinction rates can be estimated and other components of biodiversity can be measured.
The occurrence of petroleum
Authors: Stoneley Robert
Published: November 2023

Except in the case of dry gas (see below), petroleum consists of variable mixtures of the chemical substances known as hydrocarbons. The molecules of these, as the term suggests, are made up predominantly of atoms of carbon and hydrogen in varying abundances, arranged and linked together in many different ways. Some other elements may also be present: oxygen, nitrogen, sulphur, and metals such as vanadium, copper, and nickel. The molecules can be large and extremely complex. They are commonly described and depicted by semi-graphical chemical formulae, of which a few of the simplest are shown in Fig. 2.1; the formulae of complex ones, even using a form of short-hand, may cover a page!

Many hundreds (literally) of these compounds are present in a single crude oil, and it is their variety that accounts for the wide range in the properties and appearance of oils. The majority of the hydrocarbons fall into three families, the names of which may be familiar to the non-chemist (Fig. 2.1):
Human adaptability research methodology
Authors: Ulijaszek Stanley J
Published: November 2023

A. C. Haddon, in his History of anthropology, divided anthropologists into two classes: field-workers and arm-chair workers (Haddon 1910); the fonncr were seen as collecting the data which the latter might ‘weld into coherent hypotheses’. However, he was quick to point out that ‘the most valuable generalisations are made when the observer is at the same time a generaliser’ (Quiggin 1942). Although a higher value has often been placed on the thinker and generalizer (Parkes 1985; Lasker, 1993), observation, data collection and hypothesis testing based on a wide variety of data have been the hallmark of human adaptability (HA) research. In this chapter, methods employed in HA research from the time of the International Biological Programme (IBP)/HA onward are reviewed, and possible methodological avenues for the future are considered.
The model family
Authors: Mock Douglas W , Schwagmeyer P L , Parker Geoffrey A
Published: November 2023

From a comparative perspective, monogamy is a truly anomalous mating system. Its relative scarcity makes intuitive sense when one recognizes that the anisogamy1 that formally defines males (as the purveyors of small gametes) typically leaves them less constrained by parenting tasks (e.g. Bateman 1948; Parker et al. 1972; Trivers 1972). Most males manifest their relative irresponsibility by departing right after insemination, often to seek further mating opportunities. What makes monogamy special as a mating system, then, is the spectacle of males remaining in the picture after fertilization and continuing to invest in their offspring. While it is possible for males to be monogamous for relatively ignoble reasons (e.g. inability to attract additional mating partners), the phenomenon in need of special explanation is the pattern of sizeable male investment that is not met with immediate desertion by the female (as occurs in many polyandrous taxa): in short, we come quickly to the matter of biparental care.
Protozoa, helminths, and arthropods of birds
Authors: Janovy John
Published: November 2023

An enormous body of art, poetry, music, literature, popular science writing, and an equally impressive scientific literature, has grown out of our fascination with birds. In surveying the parasitological literature, one can’t help but feel as if the worms, mites, and lice have been no less fascinated with birds than have humans. Every species of bird that has been studied carefully has been shown to be a host for at least one, and often several, species of parasites. The overwhelming majority of free-living animals are small ectotherms, and while these play host to a large diversity of parasites, it is the large endotherms that support truly rich parasite species assemblages. And among the large endotherms, some of the truly astounding parasite faunas are found in/on birds. A number of parasite groups attain their highest diversity in birds, most notably insects of the order Phthiraptera (formerly Mallophaga), protozoan intracellular blood parasites, and possibly some tapeworms. The number of species of protozoans, helminths, and arthropods that parasitize birds is enormous. The following discussion merely covers the tip of the iceberg.
Freeing the mind
Authors: Lovelock James
Published: November 2023

Lovelock’s formal training was as a chemist, and until 1961 he worked at the National Institute for Medical Research in London. Then he left, and has since financed himself through inventions and consultancies. This has allowed him to pursue the research project for which he is best known, the quest for Gaia.
Not a company man
Authors: Cairns John
Published: November 2023

The overwhelming impression from the scientific literature is that researchers are an orderly lot who spend their time working in groups and turning out innumerable publications. john Cairns is not like that at all. He is a brilliant and original experimentalist whose career has been shaped as much by accident as design. Working mainly alone, and publishing relatively little, he has tacked across continents and disciplines, challenging orthodoxy as he goes. Some of his most recent experiments, which he undertook in the context of cancer research, have upset the evolutionary establishment.
The study of mass extinctions
Authors: Hallam A , Wignall P B
Published: November 2023

Having been largely ignored throughout most of the history of paleontological and geological research, the subject of mass extinctions has emerged within the last couple of decades as one of the most lively and contentious issues in the whole of science. Not only the Earth sciences community but also physical and biological scientists have involved themselves in the debate, and the media have exhibited intense interest.
Chromatin domains and boundary elements
Authors: Corces Victor G , Gerasimova Tatiana I
Published: November 2023

The temporal and spatial expression of eukaryotic genes is regulated by transcription factors through their interaction with enhancer elements. After this initial interaction, enhancer-bound transcription factors cause changes in the transcription complex assembled on the promoter to activate transcription (Thompson and McKnight 1992). The mechanisms of this activation are not well understood and several alternative mechanisms have been put forward to explain this process. Transcriptional activation might involve direct protein-protein interactions through the looping of intervening sequences that separate enhancers and promoters, tracking of the transcription factors from the enhancers to the promoter, changes in chromatin structure that take place upon factor binding to its target sequence and can be transmitted to the promoter to activate transcription, or localization to a particular nuclear compartment that is permissive for gene expression. Independent of the particular details of the process, the intrinsic nature of enhancer-promoter interactions lacks the necessary specificity required for the precise temporal and spatial patterns of gene expression that underlies the development of eukaryotic organisms. To account for the observed specificity in enhancer-promoter interactions it has been proposed that the eukaryotic genome has organizational properties that rely on the ability of chromatin to establish autonomous functional units delimiting levels and patterns of gene expression. Functional specificity of transcriptional enhancers might then be imposed by the existence of chromosomal domains, discrete and topologically independent units of gene expression in which transcription from a specific promoter results only from activation by enhancers located within the same domain, whereas enhancers in a second domain are unable to act on a promoter located in the first one.
Nuclear matrix-associated regions
Authors: Ludérus M E Eva , Driel Roel
Published: November 2023

Eukaryotic interphase chromosomes are thought to be organized in topologically independent loop domains. Such loops can be visualized emanating from permeabilized nuclei after extraction of histone proteins (Vogelstein et al. 1980; Jackson et al. 1984; Gerdes et al. 1994). At their bases the loops are fastened to the residual nuclear structure, which is known as nuclear matrix or nuclear scaffold. It is believed that the loop organization of chromatin is important not only for the compaction and spatial organization of the chromatin, but also for the regulation of gene expression. Each loop domain may represent an independent unit of chromatin structure and gene activity.
Mechanisms of heritable gene silencing during development of Drosophila
Authors: Breiling Achim , Paro Renato
Published: November 2023

An unsolved problem in the field of developmental biology is how a determined state can be faithfully maintained over many cell generations. Genetic analysis in Drosophila uncovered two classes of genes which play a role in such a process. The Polycomb group (PcG) and trithorax group (trxG) genes were first identified as transcriptional regulators of homeotic selector (HOM) genes. They maintain the differential expression pattern of these important determining factors by keeping either the inactive (PcG) or the active state (trxG) during development. The two groups are not directly involved in the process of pattern formation. They are responsible for ‘freezing’ a developmental decision, such that during the differentiation process appropriate structures can be generated based on the committed programmes of the cells. In Drosophila it was found that the mechanisms of pattern formation rely heavily on differentially localized molecules (morphogens, region-specific transcription factors, etc.). On the other hand, the process of maintaining a determined state, also called ‘cellular memory’, appears to rely on molecules that are expressed in every cell of the developing fly. How can such a set of homogeneously distributed factors memorize differentially determined states of cells? There is increasing evidence that the proteins encoded by the PcG and trxG genes exert such a regulatory role at the level of chromatin structure. Differential patterns of gene expression are encoded in higher order chromatin structures and are epigenetically transmitted from one cell generation to the next.
Woodland, scrub, and hedgerow
Authors: Gilbert Oliver L , Anderson Penny
Published: November 2023

Woodland habitat creation entails creating woodland communities that have a diverse structure and contain a wide range of tree, shrub, and ground flora species. It involves making many desisions, one of the most important of which concerns the origin of the material to be used. Here there is a range of choices (Peterken 1995), which become progressively less rigorous: Purists advocate the use of local genetic stock; however, this is rarely available in the quantities required, so the second definition has to be employed using commercially obtained nursery material. The realities of imposing the strictest policy in relation to major timber species, such as oak (Quercus spp.), which have been widely planted in the past, need to be recognized and not allowed to hinder woodland creation.
Heath and moor
Authors: Gilbert Oliver L , Anderson Penny
Published: November 2023

Heath and moor are used here in a general sense to embrace all the plant communities, excluding grasslands, that are associated with heathlands and moorlands. In practical terms, the focus is on dwarf-shrub heath, especially heather (Calluna vulgaris), because this is where most habitat creation experience lies. In addition, some attention will be paid to the associated plant communities of wet heath, valley bog, and blanket bog. For simplicity, the generic term ‘heathland’ is used to cover the whole range of such communities in the uplands and lowlands.
Montane and submontane habitats
Authors: Gilbert Oliver L , Anderson Penny
Published: November 2023

This section deals with habitat creation where high altitude or latitude, shallow infertile soils, and the severity of the climate render the communities vulnerable to both natural and human damage. The main threats are the development of ski facilities, damage from trampling, and localized construction or mining projects. On the scale of change in montane and submontane areas, none of these are large or extensive compared with the degradation of communities as a result of overgrazing by sheep and deer (Thompson et al. 1987). Reversal of these effects is more the subject of habitat restoration than habitat creation or repair. Although not at the same elevation, there is a considerable and relevant North American literature relating to the repair of tundra damaged by oil related development or strip mining.
The mollusca: coelomate turbellarians or mesenchymate annelids?
Authors: Haszprvnar Gerhard
Published: November 2023

Questions about the origin of the Mollusca and their closest relatives (i.e. their sister group) are as old as Malacology itself. As reviewed in detail by Ghiselin (1988) two main theories have been formulated. Table 1.1 summarizes current opinions and recent references. Many authors have argued on various lines of evidence that the molluscan ancestor was a turbellarian-like organism (Thiele, 1902; Hammersten and Runstrom, 1926; Vagvolgyi, 1967; Salvini-Plawen, 1968, 1972; Table 1.1). It is significant that the majority of these authors investigated aculiferan molluscs. Concerning character evolution most basic assumptions of these authors are additive, meaning that starting from a turbellarian-like ancestral condition specific characters were added or modified towards a higher (more complicated) level of organization.
Allozyme variation in some cretan albinaria (gastropoda): paraphyletic species as natural phenomena
Authors: Schilthuize Menno , Gittenberger Edmund
Published: November 2023

The genus Albinaria, represented in Greece, western and southern coastal Turkey, Cyprus and The Lebanon, is extremely speciose. Currently, about 80 species are recognised (Nordsieck, 1977; personal observations). All these snails live, often in large numbers, on or near limestone rocks, where they feed on microflora. This ecological similarity may explain why their diversity is mainly allopatric (sensu Solem, 1984): morphologically characterised species are confined to relatively small geographic areas which do not or hardly overlap. Gittenberger (1991) considered this pattern of diversity to have resulted from “non-adaptive radiation”, the term non-adaptive referring not to any supposed neutral type of evolution, but used in contrast to “adaptive radiation”, where speciation is accompanied by conspicuous nichesegregation.