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Periglacial and terrestrial habitats in polar regions

David N. Thomas, G.E. (Tony) Fogg, Peter Convey, Christian H. Fritsen, Josep-Maria Gili, Rolf Gradinger, Johanna Laybourn-Parry, Keith Reid, and David W.H. Walton

in The Biology of Polar Regions

This chapter discusses the terrestrial ecosystems of the Arctic and Antarctic. It begins discussing some of their physical and chemical characteristics and then subsequent subsections detail the ... More

This chapter discusses the terrestrial ecosystems of the Arctic and Antarctic. It begins discussing some of their physical and chemical characteristics and then subsequent subsections detail the ecosystems and their component biota. Topics covered include substrata (exposed rock surfaces, endolithic habitat, rock debris, permafrost, and polar soils); communities of the Continental Antarctic, Maritime Antarctic, High Arctic, Arctic tundra, and Antarctic tundra; the physiological ecology of polar plants and invertebrates, specialized communities; and comparison of Arctic and Antarctic terrestrial habitats and communities.Less

Conclusions: An Ecosystem Perspective of Shallow Marine Reefs

Tim R. McClanahan and George M. Branch

in Food Webs and the Dynamics of Marine Reefs

This chapter summarizes what the authors consider to be the key and general organizing principles of kelp forests and coral reefs along gradients of oceanography, latitude, and effects of fishing and ... More

This chapter summarizes what the authors consider to be the key and general organizing principles of kelp forests and coral reefs along gradients of oceanography, latitude, and effects of fishing and resource use on these ecosystems. The general structure of these food webs is described as well as the effects of top-down versus bottom-up controls and the prevalence of trophic cascades. Human effects and recommendations for management are presented.Less

Seeing in depth in different species

Ian P. Howard and Brian J. Rogers

in Seeing in Depth: Volume 1: Basic Mechanics/ Volume 2: Depth Perception 2-Volume Set

This chapter discusses depth vision in animals other than cats and primates. These include invertebrates, fish, amphibian, reptiles, birds, and mammals.

The mangrove community: marine components

Peter Hogarth

in The Biology of Mangroves and Seagrasses

This chapter discusses the marine components of mangroves. Mangroves provide marine organisms with both a physical environment and nutrients. Pneumatophores and prop roots greatly expand the surface ... More

This chapter discusses the marine components of mangroves. Mangroves provide marine organisms with both a physical environment and nutrients. Pneumatophores and prop roots greatly expand the surface area available and provide a hard substrate, in contrast to the surrounding mud, while the primary production of mangroves supplies an energy source for many organisms. These marine components include algae, fauna of mangrove roots, invertebrates, molluscs, meiofauna, and fish.Less

“Zoological Introduction” to Between Pacific Tides

Katharine A. Rodger

in Breaking Through: Essays, Journals, and Travelogues of Edward F. Ricketts

Edward F. Ricketts revised the original draft of Between Pacific Tides throughout the early 1930s, appending his four-page “Zoological Introduction,” in which he defended the book's ecological ... More

Edward F. Ricketts revised the original draft of Between Pacific Tides throughout the early 1930s, appending his four-page “Zoological Introduction,” in which he defended the book's ecological arrangement as “a natural history in every sense of the word.” In this introduction, he notes that arranging Between Pacific Tides according to shore habitats “necessitated a great amount of field work, most of which could have been obviated if the traditional treatment had been used.” Despite the establishment of academic thinking against which he worked, Between Pacific Tides is Ricketts's most recognized scientific achievement, and is revered as a classic and pioneering text in marine biology. In this work, the distribution of Pacific littoral invertebrates within a given region is seen in the light of competition and interrelation between the animals themselves, and the limiting aspects of the following factors: wave shock, tidal level, and type of bottom, along with a good many others of lesser importance, such as temperature, stagnation, silting, etc., all pretty well intermingled and interdependent.Less

The Eye Designs of the Animal Kingdom

Thomas W. Cronin, Sönke Johnsen, N. Justin Marshall, and Eric J. Warrant

in Visual Ecology

This chapter studies the eye designs of the animal kingdom. Today, there are ten generally recognized optical eye types that have evolved in various branches of the animal kingdom. Whereas ... More

This chapter studies the eye designs of the animal kingdom. Today, there are ten generally recognized optical eye types that have evolved in various branches of the animal kingdom. Whereas vertebrates possess only one of them, invertebrates possess all ten, from simple assemblies of photoreceptors that underlie phototaxis to advanced compound and camera eyes that support a sophisticated range of visual behaviors. Some invertebrates even possess several eyes of more than one type. The chapter identifies some of these eye types in the context of sensitivity and resolution, namely, pigment-pit eyes, compound eyes, and camera eyes. The last of these are characteristic of the vertebrates, although they are also commonplace among the invertebrates. The remaining nine eye types are found only within the invertebrates.Less

Neural Circuits: Spinal Cord, Retina, Invertebrate Systems

Gordon M. Shepherd

in Creating Modern Neuroscience: The Revolutionary 1950s

In the 1950s, the microelectrode opened the door not only to understanding the properties of the individual nerve cell, but also to how they are connected; how they “talk” to each other. Two ... More

In the 1950s, the microelectrode opened the door not only to understanding the properties of the individual nerve cell, but also to how they are connected; how they “talk” to each other. Two philosophies emerged. One was to aim at working out connections in order to build up the circuits responsible for the responses of the cells. The other approach was to record and characterize the responses of the cells to physiological stimuli, to show what the brain does, and to leave to future work identifying the circuits involved. Both philosophies arose in the 1950s and produced dramatic results that shaped all subsequent studies of the physiology of the central nervous system. This chapter considers the spinal cord, retina, and invertebrate systems.Less

Pollination by Nonflying Vertebrates and Other Oddities

Pat Willmer

in Pollination and Floral Ecology

This chapter considers pollination by nonflying vertebrates and other oddities. It begins with a discussion of ectotherm vertebrates visiting flowers; these include fish, amphibians, and reptiles. ... More

This chapter considers pollination by nonflying vertebrates and other oddities. It begins with a discussion of ectotherm vertebrates visiting flowers; these include fish, amphibians, and reptiles. Fish are not recorded as flower visitors, but they are at least occasionally facilitators of the pollination process for shoreline pond plants, where they prey on animals that compete with or reduce pollinator populations. The chapter proceeds with an analysis of pollination by nonflying mammals such as marsupials, rodents, monkeys, and lemurs as well as flowers that they regularly visit, including ground-level (geoflorous) flowers and arboreal flowers. Finally, it examines pollination by unusual invertebrates ranging from snails and woodlice to land crabs and millipedes.Less

The Impacts of ENSO on Terrestrial Ecosystems: A Comparison With NAO

Mauricio Lima and Fabian M. Jaksic

in Marine Ecosystems and Climate Variation: The North Atlantic: A Comparative Perspective

This chapter aims to cast new light upon the preceding chapters, drawing upon the authors' experience along the western fringe of South America, especially on data gained from Chilean ecosystems. The ... More

This chapter aims to cast new light upon the preceding chapters, drawing upon the authors' experience along the western fringe of South America, especially on data gained from Chilean ecosystems. The eastern side of the tropical Pacific — where El Niño-Southern Oscillation (ENSO) plays a highly significant role — is linked closely to the NAO impacts in the North Atlantic sector. Specifically, the impacts on plants, invertebrates, amphibians, birds, and mammals are considered.Less

Consequences of Ant Invasions

Lori Lach and Linda M. Hooper‐Bùi

in Ant Ecology

Solenopsis invicta and Linepithema humile are among the most studied invasive insects but there are several other invasive ants with adverse ecological consequences. The displacement of native ants ... More

Solenopsis invicta and Linepithema humile are among the most studied invasive insects but there are several other invasive ants with adverse ecological consequences. The displacement of native ants is the best documented consequence of ant invasions, though recent research calls into question the long‐term effects of monogyne S. invicta. Other invertebrates are also affected by invasive ants, though interactions with the same taxa can vary across different parts of an invasive ant's introduced range. Stinging invasive ants, particularly S. invicta, have the greatest documented effects on vertebrates, including birds, mammals, and herpetofauna. On plants, invasive ants may displace pollinators or other floral arthropods, deter or facilitate herbivores, or affect natural enemies. Invasive ants are often poor seed dispersers relative to native ants. S. invicta nesting habits alter many soil properties, though it is unclear how extensive these changes are relative to those caused by the displaced native ants.Less

Reef Fisheries and Reef Aquaculture

Charles R. C. Sheppard, Simon K. Davy, and Graham M. Pilling

in The Biology of Coral Reefs

Fisheries are of key importance in provision of protein, livelihood opportunities and income to islanders and coastal populations with few alternative food sources, including some of the world's ... More

Fisheries are of key importance in provision of protein, livelihood opportunities and income to islanders and coastal populations with few alternative food sources, including some of the world's poorest people. The variety of reef fisheries of both invertebrate and vertebrate resources around the world is examined. Methods used and particular issues with these fisheries are discussed. Exploitation of reef resources also occurs to supply luxury food markets, and the international live reef fish trade is highlighted. The development of reef-based aquaculture is examined, and issues that need to be addressed to deliver sustainable expansion of this approach are discussed. In the face of increasing pressures on reef resources from a number of sources, resultant impacts on reef renewable resources are detailed, and potential ways in which these pressures may be managed and controlled are described.Less

Death Caps and Muscle Wasters

Nicholas P. Money

in Mushroom

Few mushroom species are regarded as poisonous, but there are cases of serious illness and lethal poisoning caused by nominally edible species. These include muscle wasting, and eventual heart ... More

Few mushroom species are regarded as poisonous, but there are cases of serious illness and lethal poisoning caused by nominally edible species. These include muscle wasting, and eventual heart failure, caused by the yellow knight mushroom. Regional differences in toxicity may explain these incidents. Wider concern is raised by experiments showing that rodents fed large doses of popular mushrooms show signs of tissue damage. It is possible that toxins may be common among mushrooms, but are usually produced in high concentrations only in the most notorious species. Poisoning by these species, including the death cap and a deadly webcap, are caused, usually, by errors in identification. Treatment options are very limited. The biological significance of mushroom toxins is unclear, but these compounds are probably active against predatory invertebrates. Mushroom toxicity has been utilized as a literary device by poets and as a hateful metaphor by fascists and Christian fundamentalists.Less

The secondary consumers: carnivores

Donald S. McLusky and Michael Elliott

in The Estuarine Ecosystem: Ecology, Threats and Management

This chapter examines the impact of the various secondary consumers on the populations of primary consumers, and how the secondary consumers share or compete for the food supplies between themselves. ... More

This chapter examines the impact of the various secondary consumers on the populations of primary consumers, and how the secondary consumers share or compete for the food supplies between themselves. Almost all the estuarine birds, fish, and crabs feed on the animals of the primary consumer trophic level, but a few birds bypass this trophic level and instead feed directly on the primary producer plants. Migrations between habitats represent a fundamental aspect of the ecology of populations and individuals. The complex movements between breeding, wintering or feeding areas during various life-history stages are often critical to the survival of species. Estuaries are viewed as critical nursery environments supporting a rich variety of seasonal visitors. The best-known examples are waterfowl, but estuaries are used in a similar way by fish and shrimps, for feeding and wintering.Less

Diversity of life in peatlands

Håkan Rydin and John K. Jeglum

in The Biology of Peatlands

Peatlands host a wide diversity of species and life forms. The plants are the most obvious, since they provide the structural foundation and are the source of organic compounds derived from ... More

Peatlands host a wide diversity of species and life forms. The plants are the most obvious, since they provide the structural foundation and are the source of organic compounds derived from photosynthesis for the sustenance of animals and microorganisms. This chapter gives an overview of important life forms and the associated diversity of fungi, microorganisms, protozoan, algae, plants, and animals within different types of peatlands, mainly in temperate and boreal areas. For both plants and animals, characteristic species are mentioned together with quantitative information about the importance and abundance of different life forms in different types of peatlands. Many organisms are useful indicators of environmental conditions, and examples of such indicators are drawn from testate amoebae, bryophytes, and vascular plants.Less

Osmoconformers Osmoconformers

Timothy J. Bradley

in Animal Osmoregulation

In the marine environment, the vast majority of organisms are osmoconformers, meaning that all of their bodily fluids are in osmotic equilibrium with the surrounding seawater. If the salinity of the ... More

In the marine environment, the vast majority of organisms are osmoconformers, meaning that all of their bodily fluids are in osmotic equilibrium with the surrounding seawater. If the salinity of the seawater should vary due to local precipitation or evaporation, the osmotic concentration of the organism's body fluids vary in concert with the change in environmental salinity. Although the organisms must osmoconform due to highly permeable body surfaces, they often regulate the ions in their blood, and always regulate the ions in their intracellular fluids. The osmoregulatory and/or ion regulatory mechanisms in echinoderms, mollusks, arthropods, hagfish, sharks, and a species of frog are provided to illustrate the diversity of organisms employing this regulatory strategy.Less

Evolution

Michael Ruse

in On Purpose

This chapter talks about evolution and its existence, although evolutionary theorizing didn't really rise above the status of a pseudoscience. People could see only too clearly that evolution existed ... More

This chapter talks about evolution and its existence, although evolutionary theorizing didn't really rise above the status of a pseudoscience. People could see only too clearly that evolution existed on the back of what many considered the very iffy ideology of cultural progress. One mark was the way in which non-professionals like Robert Chambers felt free to plunge right in with their ideas, as though they had spent their lives working in the laboratory or out in the field. It also discusses the leading professional biologist to get tangled up with ideas of evolution, French naturalist Jean Baptiste de Lamarck, who published his speculations in his Philosophie Zoologique in 1809. That he was an enthusiast for cultural progress is shown if only by the fact that, although a minor aristocrat, it was during the revolution that his career really took off. He became a world-leading invertebrate taxonomist, a scientist of deserved respect, and as such was brought right up against the issue of the end-directed nature of the features of organisms.Less