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Space and time represent two of the many dimensions specifying the scale of evolutionary change. Scale adds yet another intimidating level in attempts to thoroughly understand evolution, and even more so when merged with the complications associated with mechanics, function, and structure. Fortunately, abstract short-cuts to model evolution can be used. One effective way is to build so-called fitness-generating functions that incorporate, implicitly, many of the complex mappings embedded in the structure matrix. Fitness-generating functions (also called G-functions) are one solution to the problem of scale. This chapter shows that if the interest is micro-evolution, a G-function should be constructed to model the fitness of different alleles. If the interest is macro-evolution, the G-function should be expanded to include suites of strategy sets. Evolutionary interest should be allowed to be a sliding scale where the assumptions and simplifications that are made to answer one question at one point are different from those at another.

This chapter describes terrestrial and underwater habitats for different otter species. Results of surveys of terrestrial habitat selection based on distribution of faeces (‘spraints’) should be treated with caution. The aquatic part of the habitat is restricted by depth as well as substrate and access to prey. Different habitats are used at various times of year, and in several species the sexes use different habitats; males preferring larger rivers or more exposed coasts. Small freshwater streams are used more intensively per unit area than larger rivers. Where several species of otter occur together, they show different selection of habitat. Sea otters have a dominating effect on ecosystems through their influence on numbers of sea urchins, which graze sea algae vegetations. For several otter species using marine habitats, the presence of freshwater sources (for cleansing fur) is essential; numbers of otter dens (‘holts’) and freshwater sources are correlated.

Movement is a fundamental process that enables individuals to find food or mates, locate suitable habitat, and colonize new areas. The effect of environmental heterogeneity on individual movement behavior is the finest scale at which organisms respond to landscape structure, and can be used to define different species’ perceptions of landscape structure. This chapter discusses different types and scales of movement, how patch structure is expected to influence movement, and various methods for tracking and analyzing animal movement. Because animal movements are typically bounded in space, the estimation of space utilization and home-range size is also considered in this chapter. The chapter concludes with a discussion of various approaches to measuring plant dispersal, which is likewise important for evaluating how movement (via propagules) translates into the redistribution or spread of populations across the landscape.

It has long been considered that abiotic factors are far more important than biotic variables in controlling the structure of desert communities. In recent years, this perception has changed because some prime examples of species interactions have come from experimental studies in desert ecosystems. Few will doubt that desert rodents present some of the best evidence for competition. Reviews also indicate that competition occurs among desert plants. This chapter focuses on some of the key competitive interactions and facilitation among desert organisms, drawn from several deserts. A great number of shrubs have been shown to have nurse plant effects on annual plants in particular, although other shrubs and geophytes may also benefit from this. Essentially, this means that the annual plants grow up under the shrub and benefit from a number of factors. The chapter also discusses indirect interactions, keystone species, priority effects and short-term apparent competition.

This chapter introduces mathematical and statistical modelling approaches to study the ecology of movement. It starts with a conceptual section, continues with mathematical and statistical sections, and ends with a perspectives section. The conceptual section motivates the modelling approaches by providing the necessary background to movement ecology. The mathematical sections first introduce random walk and diffusion models in homogeneous space, and use these models to illustrate the relationship between the Lagrangian and the Eulerian viewpoints. The movement models are then expanded to heterogeneous space, and in particular to highly fragmented patch networks. To illustrate the interplay between models and data, the statistical section analyses data generated by the mathematical models, with emphasis on the analyses of tracking data and capture-mark-recapture data.

Following wild birds marked with radio tags is a technique that can be used to obtain data on movements, survival, and habitat selection. This chapter considers the choice of type of tag and attachment method most likely to achieve useful results without adverse effects on the bird. Techniques and equipment for tracking are described, and methods and software for recording and analysing tracking data are introduced. The relative merits of radio-tracking and other, less intensive, field methods are compared. Probable future developments in equipment and their implications for field studies are considered.

This chapter focuses on the relationship between the Normalized Difference Vegetation Index (NDVI) and wildlife management, exploring the potential of the NDVI in understanding the factors that influence habitat use and selection and the prediction of animal abundance. It studies the relationship between NDVI variability and life history traits, considering the role of the NDVI in the variability in animal body mass, survival, and recruitment. It also presents the use of NDVI in studying the patterns of animal movement.

This chapter begins by discussing the variety of habitats that are occupied by fish eggs and larvae; these habitats include the open ocean, coastal ocean, and estuaries. Also, the chapter discusses the stage-specificity of the area of occurrence of each stage (adults, eggs, larvae, juveniles) in the life history of fishes, pointing out the differences of demersal, pelagic, neustonic (associated with the very surface of the water), anadromous (fish that migrate from the ocean to fresh water to spawn), catadromus (fish that migrate from fresh water to the ocean to spawn), and estuarine or coastal fishes. The effect of human activity and pollution on water quality and fish habitats is discussed as well. This chapter also discusses conservation biology, marine protected areas, and fisheries management.

Spatial resource gradients, processes of plant maturation, and grass-grazer interactions are among the biophysical factors that structure ungulate movement systems, irrespective of whether the animals are domesticated or wild. Not only do pastoralists move their herds in response to these constraints and opportunities, but also to achieve a variety of cultural, social, and economic goals. Density dependent theories of habitat selection provide only a partial explanation for land use systems that must balance the need to distribute livestock with respect to available resources with the restrictions of property rights and administrative boundaries. This chapter considers the social and economic constraints and incentives that influence livestock movements, using several case studies of contemporary domestic livestock systems (in the Sahel, Mongolia, and the Arctic). In so doing, it aims to develop an understanding of livestock mobility that recognises but does not exaggerate the biological processes that underpin this distinctive form of agricultural production.

Organisms can respond to environmental change by modifying their behavior to obtain an instant response, through short-term phenotypically plastic, often physiological, adjustments, and/or by adapting their life history through a more long-term evolutionary response. Behavioural and physiological responses, in fact, can occur at all these three temporal scales. Examples of behaviors so affected include congregation, dispersal, foraging, migration, or mating. Such responses have consequences at the population and community levels, and ultimately for the evolution of species. This chapter discusses insect examples of these kinds, with an emphasis on human-induced factors, such as (primarily) climate change, pollution, fragmentation, and urbanization.