bluuebunny/crossref_metadata_2025 huggingface dataset:
A dental microwear study of pig diet and management in Iron Age, Romano-British, Anglo-Scandinavian, and medieval contexts in England
Authors: Wilkie Tom , Mainland Ingrid
Published: November 2020

Insight into the diet of domestic animals in the archaeological record can elucidate diverse activities pertaining to ancient agricultural systems, including the utilization of the landscape by livestock and their herders (Bocherens et al. 2001; Bentley et al. 2003; Charles & Bogaard 2005), the impact of livestock farming on the environment (Amorosi et al. 1998; Witt et al. 2000; Mainland 2001), seasonality in husbandry practices (Akeret et al. 1999; Akeret & Rentzel 2001; Charles & Bogaard 2005), animal productivity (Amorosi et al. 1998) and the role of animals in society (Moens & Wetterstom 1988; Mainland & Halstead 2004). Research into the diet of domestic livestock has, however, largely focused on cattle, sheep, and goats (see for example all the references cited above) and it is only relatively recently that palaeodietary studies have begun to consider suid diet/nutrition and its potential value for elucidating the socio-economics of pig husbandry (e.g. Ervynck et al. this volume). This article presents one further such study: an analysis of dental microwear patterning in domestic pigs from selected Late Iron Age to medieval contexts in England, undertaken as part of a wider project into the potential application of dental microwear analysis to the question of pig diet and management in the prehistoric and historic past (Mainland et al. in prep.). Dental microwear analysis, although still primarily used within palaeontology (Teaford 1994; Rose & Ungar 1998), is increasingly being applied in archaeology to reconstruct both human (Rose & Ungar 1998; Schmidt 2001) and animal diet (Beuls et al. 2000; Mainland & Halstead 2004). In common with many other palaeodietary techniques (e.g. Schwarcz & Schoeninger 1991), dental microwear will not identify the consumption of individual foodstuffs but rather reflects broad functional and/or dietary adaptations (Rose & Ungar 1998); for example, browsing vs grazing (Solounias & Hayek 1993), folivory vs frugivory (Teaford & Walker 1984), hard vs soft diet (Teaford & Oyen 1989). Preliminary studies in modern suid populations have indicated that one basic axis of variation in pig diet/management is potentially identifiable using dental microwear, namely the separation of indoor-reared/stall-fed and outdoor reared/rooting populations (Ward & Mainland 1999).
Wild boar hunting in the Eastern Mediterranean from the 2nd to the 1st millennium BC
Authors: Dalix Anne-Sophie , Vila Emmanuelle
Published: November 2020

Recent studies of the archaeozoological material from the site of Ras Shamra- Ugarit and of related textual sources have been added to the archaeological data; these studies demonstrate in an unexpected manner the importance which the wild boar held on this site during the Late Bronze Age. Is this importance characteristic of Ugarit or of the Late Bronze Age? This question encouraged us to look for traces of wild boars and wild boar hunting in the osteological, iconographic, and textual data for this period in neighbouring regions. This study represents the first stage in research which is intended to be carried out in more detail. Thus here we will only propose avenues for reflection. The site of Ras Shamra on the Syrian coast corresponds to the ancient city-state of Ugarit, the flourishing capital of a small coastal kingdom. Its key geographical situation and its port rendered it a point of contact between Mesopotamia and the Mediterranean world. The city prospered in the Late Bronze Age before being destroyed by the ‘sea people’ in about 1180 BC. The ‘sea people’ and the ‘people from the North’ are known exclusively from Egyptian sources (Ramsès III, Medinet Abu). They are considered to be the destroyers of almost all the Levantine cities of the coast at that period. The excavations of the port (Minetel- Beida), the royal palace, the sanctuaries, and the residential quarters have produced many objects which are evidence of relations with Egypt, Cyprus, and Anatolia, as well as exceptional archives (2nd millennium BC)—numerous economic, administrative, literary, and mythological texts on clay tablets. Ugarit was an important commercial crossroads (Yon 1997). The archaeozoological study carried out on nearly 7000 bone remains reveals a food economy based on the breeding of cattle, sheep, and goats (Vila in press c). Evidence of pig rearing was not found. Hunting was not a common activity, being concentrated mainly on deer and sometimes wild boar. Although its domestic equivalent the pig was not bred at Ugarit, the wild boar was hunted and consumed on the site: 22 remains, some with butchering marks, provide the evidence (Vila & Dalix 2004).
Communities: patterns
Authors: May Robert M. , Crawley Michael J.
Published: November 2020

In all areas of ecology, from studies of individual organisms through populations to communities and ecosystems, there have been huge empirical and theoretical advances over the past several decades. Our guess—a testable hypothesis—is that the worldwide research community of ecologists has grown by roughly an order-of-magnitude since the 1960s, as is of course true for other areas of the life sciences. One consequence is that it is harder to put together a book like the present one. And we find it especially hard when we compare this chapter on community patterns with the corresponding chapter in the second edition of Theoretical Ecology. For the chapters on single populations, for example, there has been growth both in understanding the nonlinear dynamical phenomena that can arise, along with a host of well-designed field and laboratory experiments which illustrate these processes. The narrative, however, retains a unifying central thread, and much of the task of overview and compression lies in choosing good examples from an increasing panoply of choice. For communities, on the other hand, we find so many different yet intersecting areas of growth, many of which have recently produced booklength collections of papers, that the task of choosing which topics to emphasize and which to elide is invidious. The result is necessarily quirky. Without further apology, here is an outline. One broad area of community ecology deals with models for the dynamical behaviour of collections of many interacting species—either within a single trophic level or more generally—essentially as a scale-up of models for single and pairwise- interacting populations. This was the subject of the preceding chapter. Here, we begin by emphasizing the importance of work which views communities from, as it were, a plumber’s perspective, looking at patterns of flow of energy or nutrients or other material. But we then move on quickly to other topics. These include: the network structure of food-webs (connectance, interaction strengths, etc.); what determines species’ richness (niche versus null models); relative abundance of species (observed patterns and suggested causes); succession and disturbance; species–area relations; and scaling laws (with suggested connections among some such laws).
Fisheries
Authors: Beddington John R. , Kirkwood Geoffrey P.
Published: November 2020

The depletion of fish stocks on a global scale is well documented. The United Nations Food and Agriculture Organisation collects statistics on fisheries from all states and, despite obvious shortcomings in the data, a clear picture has been available for some time. Garcia and Grainger (2005) have succinctly documented the position from the latest available date: in 2003, only 3% of stocks were underexploited and 26% moderately exploited, while 52% were fully exploited, 16% were overfished, 7% were depleted, and 1% were recovering from earlier depletion. These global statistics mask two important phenomena. The first, highlighted by Pauly et al. (1998), is that fisheries are increasingly focusing on species lower down in the food-web and the second, highlighted by Myers and Worm (2003, 2005), is that large predatory fish have been particularly reduced in abundance. Both of these analyses are somewhat flawed. In the case of Pauly et al. there are two problems: the first is that the metrics used for the mean trophic level are presented as simple numbers with no estimates of error or indeed sensitivity. In such a situation, the changes in mean trophic levels are hard to interpret, particularly where the mean trophic level changes by at most around 10% over four decades. The second problem has been highlighted by a recent paper by Essington et al. (2006). They point out that in the periods when according to the analysis of Pauly et al. the mean trophic level was declining, in most cases catches of apex predators and indeed all upper trophic levels increased (an exception is the North Atlantic). In the case of the Myers and Worm analysis, they used the catch per unit of effort (CPUE) as an index of abundance. As discussed later in this chapter, there are problems with this, but more importantly for some key apex predators, in particular large tunas, the CPUE declines in the early stages of the fishery, where catches are small, but remains relatively stable under a regime of much higher catches. In such a situation, the interpretation that the CPUE reflects changes in abundance is clearly problematic.
Climate change and conservation biology
Authors: Kerr Jeremy T. , Kharouba Heather M.
Published: November 2020

It is increasingly recognized that, as a result of ever-growing atmospheric inputs of greenhouse gases like carbon dioxide from the burning of fossil fuels, the climate is changing regionally and globally. This has been affirmed, in light of increasing scientific understanding, in the latest report of the Intergovernmental Panel on Climate Change (IPCC) in 2001, by the US National Academy of Sciences in its 2001 report, and most recently by a statement from the Science Academies of all G8 countries, along with China, India, and Brazil. This latter statement calls on the G8 nations to ‘Identify cost-effective steps that can be taken now to contribute to substantial and longterm reduction in net global greenhouse gas emission [and to] recognize that delayed action will increase the risk of adverse environmental effects and will likely incur a greater cost’. Global warming caused by elevated greenhouse gas levels is expressed with long time lags, which can be difficult to appreciate by those unfamiliar with physical systems. Once in the atmosphere, the characteristic residence time of a carbon dioxide molecule is a century. And the time taken for the ocean’s expansion to come to equilibrium with a given level of greenhouse warming is several centuries. If current trends continue, by around 2050 atmospheric carbon dioxide levels will have reached more than 500 parts per million, which is nearly double pre-industrial levels. The last time our planet experienced levels this high was some 20–40 million years ago, when sea levels were around 100m higher than today. It can also be difficult to relate intuitively to the seriousness of the roughly 0.7 °C average warming of the Earth’s surface over the past century. And the warning by the IPCC in its 2001 report, that global warming would be in the range of 1.4–5.8 °C by the end of this century, may also seem unalarming when we experience such temperature swings from one day to the next. There is, however, a huge difference between daily fluctuations, and global averages sustained year on year; the difference in average global temperature between today and the last ice age is only around 5 °C.
Echoes
Authors: Zalasiewicz Jan
Published: November 2020

It would seem to be like searching for a needle in a haystack. One hundred million years on, strata containing recognizable fossils of multicellular creatures will extend through a 640-million-year span in time, and will have piled up, in total, to many kilometres in thickness. Somewhere in those endless stretches of rock might be the layer in which traces of humanity may be preserved, awaiting discovery by our curious visitors. Would they happen upon this by chance? Or would they be led to it by following a trail of clues, much as a detective is led to the perpetrator of a crime by the ripple effects of the act itself: the wealth gone astray, the scattered victims, the damaged property, the spree in Monte Carlo. In the case of humanity, there have been victims, and damage, and stolen wealth. It has been a quite singular felony. It will leave echoes, collateral changes, that may act, in the far future, as signposts. Some of these may give clear directions to a heist that was quite out of the ordinary. On a planetary scale, in fact. But first, how thick a section of strata should we take, as the geological target to be searched for, analysed, interpreted for signs of a vanished civilization? One might start by taking ten thousand years’ worth. To us, that represents a gigantic stretch of time (just imagine trying to peer ten thousand years into the future). Geologically, it barely counts. There are a hundred such intervals in a million-year span, and a million-year span represents the small change of geological history. Nonetheless, there are good reasons for choosing this duration, for it represents the span during which human activities can be said to have left a detectable imprint upon the geological record—an imprint beyond the odd vanishingly rare bone of an obscure bipedal hominid. Ten thousand years ago, half of the large mammals of the Earth abruptly disappeared, and it seems increasingly likely that this disappearance was mainly the result of hunting by humans.
Body of Evidence
Authors: Zalasiewicz Jan
Published: November 2020

The most direct legacy that we can leave to future geology is that of our own mortal remains. Today, in reconstructing the long-vanished Jurassic landscapes, we put the mighty, charismatic dinosaurs square in the foreground. This focus we have—well-nigh a fixation—seems to us almost self-evident. Were they not the rulers of their empire, just as we are of ours, literally bestriding their domain as colossi of scale and blood and bone? Their skeletons, avidly sought, intensely studied, painstakingly reconstructed in museum displays, are the symbols of those times, iconic, mesmerizing. Might we not hope for similar awe and reverence from our future excavators? There is no guarantee, of course, that these as yet unborn explorers of a future Earth will share this perspective. Perhaps their focus will be on what, among all the diverse living inhabitants of this planet, is most important in preserving this living tapestry. They may well regard the myriad tiny invertebrates, or the bacteria, of the world as much more important to that (in planetary terms) rare phenomenon, a stable, functional, complex ecosystem. If these future explorers took this view, at the risk of off ending what little there might then remain of our amour propre, they would have a point. Take away the top predator dinosaurs, and the Jurassic ecosystems would have been a little different, to be sure, but no less functional. Take away humans, and the present world will also function quite happily, as it did two hundred thousand years ago, before our species appeared. Take away worms and insects, and things would start seriously to fall apart. Take away bacteria and their yet more ancient cousins, the archaea, and the viruses too, and the world would die. But, let us imagine our excavators as being, in true science fiction style, just as obsessed with their relative position in the food chain as we are. Let us assume that, in their excavation of the Earth’s history, they will be looking for the power brokers of the ancient past, that they will be digging for bones and bodies.
Archaeology and the 1820 Liberal Revolution: The Past in the Independence of Greece and Latin American Nations
Authors: Diaz-Andreu Margarita
Published: November 2020

Nationalism did not end with Napoleon’s downfall, despite the intention of those who outplayed him in 1815. Events evolved in such a way that there would be no way back. The changes in administration, legislation, and institutionalization established in many European countries, and by extension in their colonies, during the Napoleonic period brought efficiency to the state apparatus and statesmen could not afford to return to the old structures. Initially, however, the coalition of countries that defeated the French general set about reconstructing the political structures that had reigned in the period before the French Revolution. In a series of congresses starting in Vienna, the most powerful states in Europe—Russia, Prussia, and Austria, later joined by Britain and post-Napoleonic France—set about reinstating absolutist monarchies as the only acceptable political system. They also agreed to a series of alliances resulting in the domination of the monarchical system in European politics for at least three decades. These powers joined forces to fight all three consecutive liberal revolutions that raged across Europe and the Americas, in 1820, 1830, and 1848, each saturated with nationalist ideals. The events which provide the focus for this chapter belong to the first of those revolutions, that of 1820 (see also Chapter 11), and resulted in the creation of several new countries: Greece and the new Latin American states. In all, nationalism was at the rhetorical basis of the claims for independence. The past, accordingly, played an important role in the formation of the historical imagination which was crucial to the demand for self-determination. The antiquities appropriated by the Greek and by Latin American countries were still in line with those which had been favoured during the French Revolution: those of the Great Civilizations. However, in revolutionary France this type of archaeology had resulted in an association with symbols and material culture whose provenance was to a very limited extent in their own territory (Chapter 11) or was not on French soil but in distant countries such as Italy, Greece, and the Ottoman Empire (Chapter 3).
Archaeology and the Liberal Revolutions (c. 1820–1860): Nation, Race, and Language in the Study of Europe’s Past
Authors: Diaz-Andreu Margarita
Published: November 2020

There was no return to the Ancien Régime after Napoleon’s downfall in 1815. Firstly, the early nineteenth-century economy was increasingly strengthened by the industrial, imperial and trading expansion of the European powers throughout the world (Chapters 5 to 10), which helped to stimulate Western Europe’s financial growth. Adding immeasurable impetus to this movement was the territorial expansion of Russia and the US, and later in the century other countries such as Japan contributed by broadening their frontiers manifold (Chapters 9 and 10). Factors such as these accelerated the enlargement and aspirations of the middle classes, who were precisely the group leading most of the revolutionary activity in the first half of the nineteenth century. Secondly, the reforms in administration made the state machine more efficient than that of the Ancien Régime and this impeded a full restoration of the old order. Also, for the efficient functioning of the state, the enthusiasm with which educated individuals identified with the nation was extremely important to ensure their loyalty. The late eighteenth and early nineteenth-century socio-political revolutions had brought a series of new meanings to concepts such as conservatism, liberal, democrat, party, and the distinction between left and right (Roberts 1996: 21). For example, liberalism was a doctrine that favoured ‘progress’ and ‘reform’. It was also linked with the type of nationalism that the French Revolution had promoted with the sovereignty of nations and the belief that all citizens were equal in the eyes of the law (although at this time ‘citizenship’, as propagated by the proponents of this doctrine, mainly meant the prosperous classes and male citizens). For progressive liberals, it was not only the established states that had the right to be a nation. The nationalist sentiments and claims by Greeks, Slovaks, Czechs, Brazilians, Mexicans, Hungarians, and a myriad of would-be nations, illustrate the growth of the widespread notion of nationhood that reached to other people with distinctive pasts and cultures. Liberals also had to confront, or negotiate with, the reactionary forces that brought down Napoleon in 1815. They were mainly made up of the nobility, and also supported by conservative intellectuals.
Evolutionism and Positivism (c. 1860–1900)
Authors: Diaz-Andreu Margarita
Published: November 2020

This was the way that one of the executive members of the Swiss National Museum phrased, at the end of the nineteenth century, the changes that had taken place in the previous decades: the interest in the national past was replacing the former emphasis on the Great Civilizations. Another transformation that had occurred was that the study of prehistory, rather than the history of the Roman and medieval periods, was definitively on the agenda. This change of emphasis, which took place between the 1860s and 1880s, had been in motion throughout the century but had finally crystallized in the last two decades of the century. By then, nationalism had transformed its character into a predominantly conservative doctrine. Another adjustment was also apparent. The acceptance of evolutionism had emerged as a major scientific theory to explain change. Issues of nationalism, regionalism, and imperialism became intertwined with scientific theory and further nourished the interest in the remote past. The development of methods to study evolution in the natural sciences promoted a scientific approach to the prehistoric period. At the same time, this affected attitudes towards the Roman and the medieval past. In this chapter, therefore, I reject the view expressed by other historians of archaeology such as Trigger (1989: 148) and to a certain degree Sklenár (1983: 123–6), who think that nationalism constituted a threat to cultural evolutionism and its eventual dismissal. This, they think, took place when scholars moved towards the adoption of the culture-historical perspective in the first decades of the twentieth century. The following pages will reveal, however, that the belief in evolutionism was not contrary to the nationalist cause. Late nineteenth-century archaeologists believed in the evolutionary theories to a greater or lesser extent. Despite this, they also became deeply implicated in the construction of their national past, to a degree not seen in previous decades. Culture-history did not oppose evolutionism; it accepted its tenets and moved beyond them.
Questions of Context: A Greek Cup from the River Thames
Authors: Bradley Richard , Smith Amy. C.
Published: November 2020

The anthropologist Mary Helms has argued that in traditional societies access to exotic items is often a source of prestige (1988: chs. 3 and 4). So is knowledge of the appropriate ways in which to use them. This idea plays a central role in a new study of the European Bronze Age which postulates long-distance links between Scandinavia and the East Mediterranean and suggests that they were a source of political power (Kristiansen and Larsson 2005: ch. 5). Similar attitudes can also be found in studies of the Iron Age. In the graves and hillforts of Hallstatt C and D there are Mediterranean amphorae, Greek and Etruscan bronze vessels and Attic (Athenian) pottery, some of which were most probably acquired through the port of Massalia. Their distribution extends over a large area north of the Alps and has been discussed by Barry Cunliffe on several occasions. As he says ‘It is difficult to resist the conclusion that the presence of the Greek trading port created a demand for commodities from the north and that this led to the emergence of powerful chiefdoms in the core of the barbarian area, able to command the flow of luxury objects from the south’ (1988: 24–5). Such interpretations emphasize the significance for Iron Age people of access to imported goods. Individual artefacts travelled even greater distances, with a major concentration of Etruscan beaked flagons in the Middle Rhine (Kimmig 1982: Abb. 32), but much further to the north and west the distribution of imports virtually runs out. That raises a serious problem. What are archaeologists to make of the few examples which have been found beyond the areas that were in regular contact with the Mediterranean? Here it is important to consider questions of context. There have been a number of reviews of the evidence for Mediterranean imports in Iron Age Britain, but they have all had one feature in common. They have catalogued a series of artefacts which were made in the Mediterranean.
The circulatory system
Authors: Atkinson Martin E.
Published: November 2020

The circulatory system has two interrelated, but distinct parts, the cardiovascular system which circulates blood around the body and the lymphatic system which returns excess fluid from the tissues to the cardiovascular system. The function of the cardiovascular system is to oxygenate blood in the lungs and distribute the oxygenated blood to the tissues of the body. At the same time, carbon dioxide that accumulates as a result of metabolism of oxygen within the tissues is removed from the tissues and transported to the lungs where it is released from the blood and exhaled. The cardiovascular system comprises the heart, a muscular pump, and blood vessels. Arteries convey blood to thin-walled capillaries where gaseous exchange takes place and veins return blood to the heart. The cardiovascular system is often described as two parallel systems; the pulmonary circulation moves blood through the lungs and the systemic circulation circulates blood through the body. Trace the circulation of blood through the two systems in Figure 4.1 by following the arrows from the side of the heart coloured red. It follows a figure-of-eight (8) pattern with the two systems interlinked at the heart, the upper loop representing the pulmonary circulation and the lower loop the systemic circulation. The heart is a muscular pump driving blood at considerable pressure through arteries that get progressively smaller in both circulations until capillaries are reached. Arteries are sometimes dismissed as mere plumbing, but they play a vital role in regulating the blood flow through organs and tissues. Capillary walls are only one cell thick, allowing for the efficient diffusion of gases and small nutrient molecules to and from tissues. Waste gases and metabolites are also returned to the circulatory system through capillaries and these unite to form veins carrying blood under comparatively low pressure back to the heart. The heart comprises two muscular pumps arranged in parallel and beating in unison. As you can see in Figure 4.1, these two pumps are designated as the right and left sides of the heart. Each pump consists of two chambers, a thin-walled atrium that receives blood from one or other circulation and a thick-walled ventricle that ejects blood into the circulations.
The autonomic nervous system
Authors: Atkinson Martin E.
Published: November 2020

A large part of the nervous system is dedicated to the control of the internal viscera and their functions. Much of the activity of these organs is controlled reflexly at the brainstem level, e.g. the cardiovascular and respiratory centres (the vital centres) in the reticular formation of the medulla controlling cardiac and respiratory activity. There are also centres in the cerebrum, notably the hypothalamus in the diencephalon. Somatic and visceral functions are closely integrated at these higher levels; think of the effect that emotional factors or somatic stimulation can have on heart rate, blood pressure, and gastrointestinal activity when we are nervous or are in pain. The nerves involved in these activities are described as visceral sensory or visceral motor nerves because they control visceral function; this distinguishes them from somatic sensory nerves from peripheral receptors and somatic motor nerves controlling voluntary function. Visceral motor neurons innervate smooth muscle and secretory cells of the gastrointestinal and respiratory systems, the smooth and cardiac muscle of the cardiovascular system, the sweat glands and arrector pili muscles of the skin, and the muscles of the ciliary body and iris of the eyeball. In many cases, there is a dual supply from the sympathetic and parasympathetic divisions of the autonomic nervous system. In both divisions of the autonomic nervous system, there is a sequence of two neurons between the CNS and the effector organ which synapse in peripheral autonomic ganglia. The neurons from the CNS to the synapse in the ganglion are the preganglionic neurons and those from the ganglia to the effector organs are the postganglionic neurons. The enteric plexus is a third set of neurons interposed between the post-ganglionic neurons and the effector cells in the gastrointestinal tract. Figure 17.1 compares the general arrangement of the sympathetic and parasympathetic nervous system. The cell bodies of sympathetic visceral preganglionic motor neurons are located in the intermediolateral horns of the thoracic and upper lumbar segments of the spinal cord while those of the parasympathetic visceral preganglionic (secretomotor) neurons are in the nuclei of four of the cranial nerves and the sacral segments of the spinal cord.
Development of the central nervous system
Authors: Atkinson Martin E.
Published: November 2020

The early development of the nervous system, the process of neurulation, has already been outlined in Chapter 8 and illustrated in Figure 8.4. To briefly recap, an area of dorsal ectoderm is induced by the underlying notochord to form the neural plate during the third week of development. The lateral edges of the neural plate rise to form the neural folds which eventually fold over and unite in the midline by the end of the fourth week to produce the neural tube. A distinct cell population on the crest of the neural folds, the neural crest, migrates from the forming neural tube to form various structures, including components of the peripheral nervous system. The closed neural tube consists of a large diameter anterior portion that will become the brain and a longer cylindrical posterior section, the future spinal cord. Initially, the neural plate is a single cell layer, but concentric layers of cells can be recognized by the time the neural tube has closed. An inner layer of ependymal cells surrounds the central spinal canal. Neuroblasts, the precursors of neurons, make up the bulk of the neural tube called the mantle layer; this will become the grey matter of the spinal cord. Neuroblasts do not extend processes until they have completed their differentiation. When the cells in a particular location are fully differentiated, the neuronal processes emerging from the neuroblasts form an outer marginal layer which ultimately becomes the white matter of the spinal cord. Figure 19.1B shows that the neural tube changes shape due to proliferation of cells in the mantle layer. This figure also indicates two midline structures in the roof and floor of the tube, known as the roof plate and floor plate. They are important in the determination of the types of neurons that develop from the mantle layer. The floor plate is induced by the expression of a protein product of a gene called sonic hedgehog (SHH) produced by the underlying notochord; the floor plate then expresses the same gene itself. Neuroblasts nearest to the floor plate receive a high dose of SHH protein and respond by differentiating into motor neurons; as seen in Figure 19.1B, these cells group together to form bilateral ventrolateral basal plates.
Embryology of the head and neck
Authors: Atkinson Martin E.
Published: November 2020

Embryology and development have been covered after the main anatomical descriptions in the previous sections, but it is going to precede them in this section. The reason for this departure is that the embryonic development of the head and neck explains much of the mature anatomy which can seem illogical without its developmental history. The development of the head, face, and neck is an area of embryology where significant strides in our understanding have been made in the last few years. The development of the head is intimately related to the development of the brain outlined in Chapter 19 and its effects on shaping the head will be described in Chapters 32 and 33. The major thrust of this chapter is the description of the formation of structures called the pharyngeal (or branchial) arches and the fate of the tissues that contribute to them. All four embryonic germ layers contribute to the pharyngeal arches and their derivatives, hence to further development of the head and neck. Figure 21.1 is a cross section through the neck region of a 3-week old embryo after neurulation and folding described in Chapter 8. It shows the structures and tissues that contribute to the formation of the head and neck: • The neural tube situated posteriorly and the ectomesenchymal neural crest cells that arise as the tube closes; • The paraxial mesoderm anterolateral to the neural tube; • The endodermal foregut tube anteriorly; • The investing layer of ectoderm. The development of all these tissues is intimately interrelated. The pharyngeal arches are very ancient structures in the evolutionary history of vertebrates. The arches and their individual components have undergone many modifications during their long history. In ancestral aquatic vertebrates, as in modern fishes, water was drawn in through the mouth and expelled through a series of gill slits (or branchiae, hence the term ‘branchial arch’) in the sides of the pharynx. Oxygen was extracted as the water was passed over a gill apparatus supported by a branchial arch skeleton moved by branchial muscles controlled by branchial nerves. Although ventilation and respiration is now a function of the lungs in land vertebrates, the pharyngeal arches persist during vertebrate development.
The oral cavity and related structures
Authors: Atkinson Martin E.
Published: November 2020

Technically, the oral cavity consists of the vestibule between the lips and cheeks externally and the teeth and alveolar processes internally and the larger oral cavity proper located internal to the dental arches. In clinical practice, the whole mouth is simply referred to as the oral cavity, but ‘vestibule’ is used for the specific area defined above. For charting of teeth and similar dental procedures, the mouth is divided into quadrants—upper right and left and lower right and left with the midline and occlusal surfaces of the teeth forming the dividing lines. It is a crucial skill for dental students and practitioners to recognize the naked eye appearance of the structures in a normal healthy mouth and variations that occur; abnormal appearances can then be recognized, diagnosed, and treated successfully. Much of the macroscopical appearance is determined by the underlying gross anatomy so this must be understood too. The best way to examine the interior of the mouth is on a subject seated in a dental chair with clinical lighting and the use of a tongue spatula and a dental mirror where necessary. However, you will be able to see most of the important features by examining the inside of your own mouth in a well-lit household mirror. The following description and illustrations apply to an adult mouth with a full secondary (permanent) dentition of two incisors, one canine, two premolars, and three molars in each quadrant, making 32 teeth in total. Apart from size, the major differences in childrens’ mouths are in the dentition. The primary (deciduous) dentition erupts into the oral cavity between the age of 6 months and 2 years. It comprises two incisors, one canine, and two molars in each quadrant, giving a total of 20 teeth. Most of the teeth of the secondary dentition erupt between the ages of 6 to 12, replacing the primary teeth; a combination of primary and secondary teeth, a mixed dentition, is found between these ages. Primary incisors and canines are replaced by their permanent successors, but the deciduous molars are succeeded by the permanent premolars; the three permanent molars in each quadrant are additional teeth.
Atmospheric Turbulence
Authors: Tuck Adrian F.
Published: November 2020

This book, authored by a well-known researcher and expositor in meteorology, focuses on the direct link between molecular dynamics, turbulence theory, fluid mechanics and non equilibrium statistical mechanics, it is relevant to the fields of applied mathematics, physics and atmospheric sciences, and focuses on fluid flow and turbulence, as well as on temperature, radiative transfer and chemistry. With extensive references and glossary, this is an ideal text for graduates and researchers in meteorology, applied mathematics and physical chemistry.
Summary, Quo Vadimus? and Quotations
Authors: Tuck Adrian F.
Published: November 2020

In this chapter, we offer a summary of the book’s results and conclusions, ask what future developments might be contemplated, both theoretical and experimental, and provide some scientific quotations which seemed relevant. The quotations are collected here rather than dispersed through the text, because some of them apply at several junctures and one or two apply to the whole book. It is hoped that they will underline some important points in a memorable and even entertaining manner. Application of generalized scale invariance to large amounts of research quality in situ airborne observations of the free troposphere and lower stratosphere has shown that the atmosphere behaves as a random, non-Gaussian, Lévy stable process. The scaling exponents describing the resultant statistical multifractality are the conservation H1, the intermittency C1 and the departure from monofractality α, the Lévy exponent. They had average values of 0.55, 0.05, and 1.6 respectively as deduced from airborne time series of wind speed and temperature. Certain regimes, such as jet streams, however showed correlation within the mean; the value of H1(s) for horizontal wind speed s was positively correlated with the magnitude of the horizontal speed shear and the value of H1(T ) for temperature was positively correlated with the meridional (equator-to-pole) temperature gradient. The value of H1(s) in the vertical showed clear correlation with vertical measures of jet stream strength, such as depth and maximum speed. The vertical scaling of temperature showed the paramount influence of gravity, having H1 close to unity, while horizontal wind speed and relative humidity were about 0.75. These results show that large scale ordered flow can be interpreted as emerging from less ordered smaller scale motions. At the same time, the smaller scale motions are never truly random in the atmosphere and the larger scale motions are never perfectly correlated, smooth flow. Ozone and water, while occasionally behaving as passive scalars, that is to say as tracers, more often showed the presence of sources and sinks: a numerical model-independent demonstration of the operation of photochemistry and precipitation respectively.
Population Changes: Magnitude, Mobility, and Disease Transfer
Authors: Cliff A. D. , Smallman-Raynor M.R. , Haggett P. , Stroup D.F. , Thacker S.B.
Published: November 2020

The human population of the earth took the whole of its existence until 1800 to build to 1 billion. By 2000 it had exceeded 6 billion, more than doubling in the twentieth century alone. In 1800, the time taken to navigate the globe by sailing ship was about a year. Today, no two cities served by commercial aircraft are more than a couple of days apart. Since this is less than most disease incubation times, infected people can travel undetected—a concern noted from the early days of commercial air travel. Within developed countries, the rate of individual circulation (in terms of average distances travelled) has increased 1,000-fold in the last 200 years. While the processes of population growth and geographical churn have been at work for the whole of human history, it is in the last two centuries that the momentum of change has gathered increasing pace. As described in Section 2.1, McMichael (2004) recognizes four separate stages. (i) Early human settlements from c.5,000 to c.10,000 years ago enabled enzootic pathogens to enter Homo sapiens populations. Some of these encounters led to the emergence of many of today’s textbook infections: influenza, tuberculosis, cholera, typhoid, smallpox, measles, malaria, and many others. (ii) Eurasian military and commercial contacts c.1,500 to c.3,000 years ago with swapping of dominant infections between the Mediterranean and Chinese civilizations. As described in Section 2.2, the plagues and pestilences of classical Greece and Rome date from this period. (iii) European exploration and imperialism from c.1500 with the transoceanic spread of often lethal infectious diseases. The impact on the Americas, on Australasia, and on remote island populations is well known; ships’ crews and passengers were the devastating vectors. (iv) The fourth great transition is today’s globalization, acting through demographic change and accelerating levels of contacts between the different parts of the world to facilitate disease emergence, re-emergence, and spatial transfer. Global warming, the destabilization of environments, the unparalleled movement of peoples rapidly across the globe through air transport, are all part of an evolving host–microbe relationship (cf. Section 1.3.1).
Controlling Re-emerging and Newly Emerging Diseases
Authors: Cliff A. D. , Smallman-Raynor M.R. , Haggett P. , Stroup D.F. , Thacker S.B.
Published: November 2020

As earlier chapters in this book have shown, cyclically re-emerging old plagues and newly emerging scourges are, because of their multifactorial ecology, likely to be the enduring experience of the human race. And so, in this concluding chapter, we look at some of the broad ideas which lie behind disease control and which might be used to mitigate the impact of new or re-emerging infections. Linked to surveillance systems, quarantine and vaccination are currently the front-line approaches, and we discuss these in Sections 11.2 and 11.3. The chapter is concluded in Section 11.4 with an assessment of the twenty-first- century context within which containment of newly emerging and re-emerging diseases is likely to occur. It is helpful to consider control strategies for communicable diseases by setting them within a modelling framework. A basic susceptible–infective– removed (SIR) epidemic model was described in Section 10.2.1. As shown in Figure 11.1, protection against the spread of infection can be undertaken at two points. The first method, (i), is to interrupt the mixing of infectives and susceptibles with protective spatial barriers. This may take the form of isolating an individual or a community, or of restricting the geographical movements of infected individuals by quarantine; another approach is by locating populations in supposedly safe areas. The historical use of quarantine in protecting communities against the plague and other diseases is considered in Section 11.2. For animal populations, there exists a third possibility: the creation of a disease-free buffer zone by the wholesale evacuation of areas or by the destruction of those infected. The second method, (ii), is to short-circuit the route from susceptibles to removed by the establishment of immunity through some variant of immunization. Vaccination as a control strategy is discussed in Section 11.3. Potential control strategies are illustrated schematically in Figure 11.2. In the two maps, infected areas have been shaded, while disease-free areas have been left blank. In Figure 11.2A, the disease-free areas need to be protected by isolation.
Hydrology and Rural Water Supply in Southeast Asia
Authors: Chuan Goh Kim
Published: November 2020

The East Asian economic turmoil of 1997 and its lingering effects belie the decade of unprecedented economic growth in the Southeast Asian region. This economic boom saw a significant increase in the per capita income of the population of the respective countries and a corresponding rise in the standards of living. The decade also saw increased government spending on infrastructural development of basic amenities, including irrigation extension and rural water supply. The demand for and consumption of water increased significantly in both cities and the rural areas. In contrast to the escalating demand for water by the economies of the Southeast Asian countries, available resources remain limited despite the fact that the region generally receives more rainfall than it loses through evaporation annually. Annual, seasonal, and spatial variations in the rainfall within and between countries on the one hand, and accelerated demands for water from the various sectors of the economy on the other, put a severe strain on the available water resource base. In addition, natural resources in the form of rivers, groundwater storage, and lakes are rapidly diminishing in quality as a result of domestic, agricultural, and industrial waste discharges. In the coastal plains, excessive groundwater abstraction resulting in salt-water intrusion has affected groundwater resources. Inland, and in the watershed areas, rapid and extensive development has been at the expense of forested land, which has given way to new urban centres and residential and industrial complexes, while uncontrolled logging and shifting agriculture have caused the deterioration of the remaining forested ecosystem and natural watersheds. Given these factors, the future water resources scenario of the region seems bleak unless urgent steps are taken to manage seriously the resources in a judicious and sustainable way. Water will certainly feature as an important issue of development in the region in the decades ahead, given that large population concentrations and economic development are located in the lower parts of river basins. This chapter describes the hydrological conditions of the Southeast Asian region and examines the nature and extent of water resources that have been put to use for rural and agricultural development.
The Iconography of Early Anglo-Saxon Coinage
Authors: Gannon Anna
Published: November 2020

This is the first scholarly art-historical appraisal of Anglo-Saxon coinage, from its inception in the late sixth century to Offa's second reform of the penny c.792. Outside numismatic circles, this material has largely been ignored because of its complexity, yet artistically this is the most vibrant period of English coinage, with die-cutters showing flair and innovation and employing hundreds of different designs in their work. By analysing the iconography of the early coinage, this book intends to introduce its rich legacy to a wide audience. Anna Gannon divides the designs of the coins into four main categories: busts (including attributes and drapery), human figures, animals and geometrical patterns, presenting prototypes, sources of the repertoire and parallels with contemporary visual arts for each motif. The comparisons demonstrate the central role of coins in the eclectic visual culture of the time, with the advantages of official sanctioning and wide circulation to support and diffuse new ideas and images. The sources of the motifs clarify the relationship between the many designs of the complex Secondary phase (c.710-50). Contemporary literature and theological writings often offer the key to the interpretation of motifs, hinting at a universal preoccupation with religious themes. The richness of designs and display of learning point to a sophisticated patronage with access to exotic prototypes, excellent craftsmanship and wealth; it is likely that minsters, as rich, learned, and well-organized institutions, were behind some of the coinage. After the economic crises of the mid-eighth century this flamboyant iconography was swept away: with the notable exeption of the coins of Offa, still displaying exciting designs of high quality and inventiveness, reformed issues bore royal names and titles, and strove towards uniformity.