Paleoecological studies can provide some insight into factors influencing a species’ present-day distribution, and its present-day distribution can, in turn, provide some insight into its future distribution. Being able to predict future distributions is very important because climate, an important influence on species distribution, is now changing at a rapid rate. Within a population, individuals may have a random, uniform, or clumped dispersion, though a clumped dispersion is most common because essential resources such as food, light, and undisturbed habitat are often spatially clumped. Distribution patterns change over the short term, as a result of dispersal, and over the long term from factors that influence range expansion and contraction. Abiotic factors, such as climate, soils, light availability and disturbance, and biotic factors, such as behavior, life histories and interactions with other species, can influence the distribution of species. Changes in these factors can lead to changes in distribution, including range expansion, range contraction and extinction. By quantitatively describing a species’ ecological niche, ecologists can understand a species’ present distribution, and may be able to make predictions about its future distribution.

The strong interactions among sea otters, sea urchins, and kelp are the basis of a trophic cascade, a community-level process that is influenced primarily by the actions of predators, and which has indirect effects at least two trophic levels removed from the actions of the predator. Ecologists explore community processes across scales of space and time to investigate whether trophic cascades such as these are common, and whether they are conditional on a particular set of environmental conditions. Ecological communities are structured by species composition and diversity, by the distribution and abundance of each species within the community, by the interactions among species, and by the presence of guilds and functional groups. In addition, community processes are strongly influenced by the actions of dominant and keystone species. Ecologists use food webs to construct a useful but incomplete picture of community structure. By quantifying certain attributes of food webs, such as linkage density and connectance, ecologists can compare food webs to identify unique features of community structure in a particular web. Food web structure and functioning are influenced by both consumers and producers. Ecologists are attempting to identify conditions under which bottom-up versus top-down processes are more likely to influence community structure

Climate change has already profoundly changed the ecological world on all levels of the biological hierarchy. Comparing the past with the present allows researchers to document that changes have happened, and to understand why some groups (e. g. birds vs. mammals in the Mojave Desert) respond differently than others. Climate change has already changed population phenology, and researchers can estimate the speed of phenological change. Population range shifts may occur on two fronts: leading-edge expansion and trailing-edge contraction. Both of these processes are influenced by biotic and abiotic factors. Climate change can also influence the genetic structure and sex ratio of populations – in extreme cases leading to extinction. Changes to the timing of migration or to the emergence of plants and insects can cause phenological mismatch of exploitative or competitive interactions. Prey species are likely to benefit, while predators or herbivores may suffer from lack of food. On a larger scale, both terrestrial and aquatic ecosystems are showing the effects of climate change, even in tropical biomes where warming and drying are not as prominent as they are in more temperate or polar biomes. Though immune to drought, marine biomes are suffering from acidification and from low oxygen levels.

Acclimatization and adaptation are two responses of organisms to a changing environment. Each species functions best in a particular thermal environment, and has adaptations that allow it to survive and reproduce successfully in that environment. The range of thermal conditions tolerated will vary with each species. Animals and plants face somewhat different challenges, as plants cannot move to a new environment, but there is also considerable overlap in how animals and plants deal with a variable thermal environment. Organisms must balance their internal water and solute concentrations within tolerable levels. Terrestrial species in dry environments have adaptations for procuring and conserving water, while aquatic species are more likely to be challenged to maintain the proper solute concentration. For many species, the problem of temperature regulation and water regulation are functionally linked, and there may be tradeoffs in how these two critical processes interact. Environmental temperature, water availability, and solute concentration influence species distribution and abundance. Climate change caused by human actions is already significantly affecting species distribution and abundance and ecosystem functioning.

Biological diversity should be viewed through the lens of genetic diversity, overall species diversity, and on a broader scale, ecosystem diversity. Small populations have very low genetic diversity, and have high probabilities of extinction. Ecologists use various types of population viability analyses to predict the probability of extinction. Field ecologists collect population data on survival of young and fecundity of females to construct life tables that help with making projections of future population growth. Immigration of individuals from nearby populations can maintain population viability and species diversity. Metapopulations are most viable when they are large and well-connected to numerous subpopulations, so they experience high immigration rates. Humans have caused the decline or extinction of many populations and species by degrading or destroying habitats, by fragmenting habitats, by overexploiting species, and indirectly by introducing non-native (invasive) species to a novel environment. Habitat destruction, habitat fragmentation, and direct exploitation of a naturally small population threaten the viability of the newly discovered Tapanuli orangutans.

Facilitative interactions include mutualisms, in which both species benefit, and commensalisms, in which only one species benefits and the second species is unaffected by the interaction. The commercially important pollination mutualism between honeybees and plants is under assault by a mysterious emerging disease, CCD. Mutualistic species play critical roles in biological communities, including coral and their algal symbionts that are the foundations of coral reef communities, and the mycorrhizal association between plant roots and their fungal symbionts that is essential for most plant communities. A facilitative interaction can benefit species either directly, or indirectly by its effect on another species. There is usually some cost to each mutualistic species; thus, mutualism is most likely to evolve if the benefits exceed the costs, and if each species can ensure that its mutualistic partner provides the appropriate benefit. Facilitation may be more common in stressful environments, where the benefits of facilitation are greater than they might be in more benign environments. Some facilitative interactions, such as the interaction between the great spotted cuckoo and the carrion crow, are beneficial under some conditions and detrimental under other conditions.

Using data from direct observations, experimental mesocosms, field experiments, and complex computer models, the IPCC has made a very strong case supporting the hypothesis that human behavior is leading to rapid and substantial climate change. One important anthropogenic effect is changes to the carbon cycle, primarily greater CO2 export into the atmosphere from industrial activity. In recent years, both oceans and terrestrial sources have taken up some of this excess CO2, but ocean uptake is particularly problematic, because it leads to acidification. There are many other important greenhouse gases that influence Earth’s surface temperatures, including methane, nitrous oxide, ozone, and a diverse group of halocarbons. Though less abundant, these gases have a much greater global warming potential than CO2, on a per molecule basis. Many effects of greenhouse gases on global climate are complex; for example, a particular halocarbon can increase and decrease surface temperatures via different mechanisms. There are many different types of climate models that use the movement of the atmosphere around Earth, and the interaction of the atmosphere with the oceans and with biological processes, to project future climate. Though there are quantitative differences between the projections of each model, these models all project a much warmer and wetter global climate over the next century, with northern latitudes experiencing the greatest impact of climate change.

The tremendous biological diversity of some plant communities may be a reflection of the variety of direct and indirect interactions that plants have with predators, competitors, and mutualists. Ecologists have several ways of measuring biological diversity; some diversity indices, such as the Shannon index, integrate species richness and evenness. Alpha diversity measures species richness within an area, beta diversity measures species turnover, while gamma diversity is the combined species richness of all communities under consideration. Biotic and abiotic factors can influence community diversity directly and indirectly. For example, in southwest Finland, host plant abundance directly and positively influenced lepidopteran species abundance. In the African savanna, herbivorous mammals indirectly and negatively affected bird diversity by consuming trees and reducing the abundance of insects that served as food for the birds. Abiotic factors influencing community diversity include the type of habitat, geological heterogeneity, nutrient levels, and the type and intensity of disturbance. Ecologists predict that diverse communities will be more stable than less diverse communities, but that the populations of species in diverse communities will be less stable.

The distribution and abundance of species is limited by the availability of nutrients and energy. Adding limiting nutrients to an ecosystem can increase the abundance of some species and may have far-reaching effects on ecosystem functioning. Conversion of light energy into chemical energy by photosynthesis is the primary method by which energy enters an ecosystem. Three different processes of carbon fixation have evolved: C3, C4, and CAM. Each process has costs and benefits that are environment-dependent, but scientists are still evaluating these. Heterotrophs get energy by consuming autotrophs and other heterotrophs. Herbivores, carnivores, omnivores, detritivores, and decomposers are the major classifications of heterotrophs and combined with autotrophs make up the organisms within a biological community. There are numerous morphological, physiological, and behavioral adaptations associated with each type of feeding. Species distribution is influenced by how the ratio of nutrients available to species affects their physiological and ecological processes. It is also influenced by the presence of predators and adaptations of prey species that reduce their probability of being eaten. Some defenses may be induced by the presence of predators.

As touched upon in Chapter 1, contemporary commentary on corporate governance can be divided into two main approaches: stakeholder primacy, and the narrower shareholder primacy. This chapter focuses on the first of these objectives. We commence the chapter by pointing out that an approach that accentuates the differences between a shareholder versus a stakeholder theory of the corporation is probably a contradiction and a false dichotomy. We then deal with the important aspect of corporate social responsibility (‘CSR’) and the related issue of disclosure of and reporting on non-financial matters. As part of this discussion we focus on the controversial and highly topical issue of companies exaggerating their image as environmentally friendly corporations (greenwashing) to please investors and to attract more investments, as well as smartening their image on other issues (greenscreening). This chapter then looks at the ‘social licence to operate’ before shifting to CSR and directors’ duties. The chapter concludes by considering the meaning of ‘stakeholders’ and how all corporate stakeholders have vested interests in the sustainability of corporations.

This chapter opens with a brief discussion of the nature of business ethics, its significance for corporations and the ethical dimensions of a corporation’s stakeholder relationships. The next section is focused on the causes of ethical problems: bad apples, bad cases and bad barrels. In order to examine these it presents the theory related to each before drawing on three case studies: the HIH failure, the LIBOR case and the destruction of Juukan Gorge. The extent to which we attempt to encourage ethical conduct is discussed in the following section. In particular, that section examines corporate accountability, individual accountability and organisation-level approaches that seek to shape the ethical conduct of corporations. The final section is devoted to some concluding remarks.

Since at least 2018 there has been a major shift within ‘Business America’ away from ‘shareholder capitalism’ towards ‘stakeholder capitalism’, a move which has already had some global impact. Our approach is, however, realistic and we also make the reader aware of the challenges for countries, particularly where shareholder primacy is deeply embedded in statutory law and case law, to move from shareholder primacy to an all-inclusive stakeholder model of corporate law and corporate governance. In this chapter we extract some of the ‘essential’ principles of corporate governance and illustrate that there is a ‘business case’ for good corporate governance. We conclude the chapter by discussing broader trends and debates with a present and likely future impact on corporate governance. These include what can be described as the ‘Fourth Industrial Revolution’; the widening gap between the ‘rich’ and the ‘poor’, or, put differently, ‘the price of inequality’; the growing problem regarding profit-sharing or capital distribution in large public corporations; and a short discussion of the so-called ‘Great Reset’.

The pion, the mediator of the nuclear force proposed in 1935 by Yukawa. The first particle discovered in the cosmic rays looked like the pion, but was later found to be a lepton, the muon. Experiments at high altitudes on cosmic rays led finally to the discovery of the pion. More experiments soon showed other surprises, the strange particles.

How the properties of the charged pion have been measured.

The discoveries of the charged leptons and of the neutrinos.

How, in 1928, A. M. Dirac found the fundamental relativistic wave equation and the Dirac Lagrangian. Dirac’s fundamental predictions of the existence for each fermion of an antiparticle with the same mass but opposite ‘charges’. How the positron and the antiproton were discovered. The important concepts of helicity and chirality.

The Majorana equation for completely neutral fermions.

This chapter is divided into three main sections. The first proposes the Ten Teacher Questions framework. This set of questions is designed to provide you with a generic framework for critical enquiry into all your pedagogical choices, and to connect your pedagogical knowledge to what you have learned in previous chapters. The second section provides the curriculum context structures ‒ that is, the ACARA Cross-curriculum Priorities and General Capabilities, which inform our work. The third section presents Teaching Ideas in Mathematics, The Arts and English. Our key message is not that you must implement every Teaching Idea! Instead, we hope the examples will consolidate a practical approach to harnessing the linguistic diversity of your students. We hope that you will grasp the principles which you can see at work in the Teaching Ideas, and the way that they respond to one or more of the Ten Teacher Questions.