Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

It is suggested that local animal species diversity is related to the number of predators in the system and their efficiency in preventing single species from monopolizing some important, limiting, requisite. In the marine rocky intertidal this requisite usually is space. Where predators capable of preventing monopolies are missing, or are experimentally removed, the systems become less diverse. On a local scale, no relationship between latitude (10⚬ to 49⚬ N.) and diversity was found. On a geographic scale, an increased stability of annual production may lead to an increased capacity for systems to support higher-level carnivores. Hence tropical, or other, ecosystems are more diverse, and are characterized by disproportionately more carnivores.

/pdf/food-web-complexity-and-species-diversity-59eo6z6mqe.pdf

Food Web Complexity and Species Diversity

ARTICLES Organic Fluorine Chemistry: C. G. Krespai.................................. Expanding rapidly, the science of these compounds has assumed both theoretical and practical importance. The Biological Synthesis of Cholesterol: K. Bloch .............................. Predation, Body Size, and Con-mposition of Plankton: J. L. Brooks and S. I. Dodson ... The effect of a marine planktivore on lake plankton illustrates theory of size, competition, and predation. 7

https://science.sciencemag.org/content/sci/150/3692/28.full.pdf

Predation, Body Size, and Composition of Plankton

The evolution of "niche breadth," or "niche width," was a more popular topic in the evolutionary ecological literature of the 1960s and 1970s than it has been recently (109, 118, 120, 134, 155, 156). This review summarizes current hypotheses on the evolution of specialization and generalization and suggests areas in which future research might be rewarding. The topic is so broad that every area of biology bears on it. We cannot hope to offer an exhaustive review of evidence and in particular have slighted much of the ecological literature to emphasize genetic and evolutionary perspectives. We limit our discussion almost entirely to animals. We adopt Hutchinson's (86) representation of a population's ecological niche as an n-dimensional hypervolume, the axes of which are environmental variables or resources. Along each of these, the population displays a wide or narrow tolerance or pattern of utilization, relative to other populations or species. Specialization and generalization must be defined with reference to particular axes (e.g. temperature, range of food particle sizes). Brown (9) suggests that niche breadth along different axes is positively correlated and that this explains positive correlations across species between local abundance and breadth of geographic range. Multidimensional specialization might be expected if species arise in localized regions that differ in several ecological respects from those occupied by parent species. Cody (20), however, suggested that the breadth of habitat is negatively correlated with diet breadth among certain bird species. In practice, quantitative measurement of niche breadth can be difficult (22,

The Evolution of Ecological Specialization

Phenotypic plasticity is the ability of a single genotype to produce more than one alternative form of morphology, physiological state, and/or behavior in response to environmental conditions. "Plasticity" and "development" are related terms that are becoming increasingly common in evolutionary biology and ecology. Both phenomena have passed through a period of neglect. In the 1960s Wigglesworth (228, p. 107) described some geneticists as being "apologetic" about environmentally cued polymorphisms, which they considered examples of unfortunate defects in the delicate genetic apparatus: "As R. A. Fisher once said to me, it is not surprising that such elaborate machinery should sometimes go wrong." And Bradshaw (19, p. 148) noted that botanists were carefully avoiding any mention of plasticity; environmental effects in experiments were considered "only an embarrassment." Until recently, genetic considerations have predominated in discussions of evolution and selection. Compared to the enormous progress made in genetics, there has been relatively little systematic effort to analyze environmental effects on the phenotype, and their evolutionary consequences. The plastic phenotype, stigmatized by poorly understood environmental influences and the ghost of Lamarck, has sometimes been lost from view as the focus of selection (e.g. 46; but see 48, 49). Much recent progress has been made toward integrating developmental and evolutionary biology, especially in vertebrate morphology (2, 12, 16, 216), developmental genetics (16, 163, 164), and molecular biology (103; also see 10, 111). "Developmental constraints" is a term symptomatic of this progress, though an unfortunate one because it seems to imply that the main effect of

Phenotypic Plasticity and the Origins of Diversity

The Cichlid fishes of the Great Lakes of Africa.

An account is given of the functional morphology, ecology, habits and - in most cases - feeding mechanisms of representatives of 13 genera of anomopod cladocerans of the family Macrothricidae. As in the Chydoridae, habits, which often depend on anatomical specializations of great complexity, are diverse, and permit the exploitation of a wide variety of ecological niches. In general, locomotion is less specialized than in the Ghydoridae and most species neither swim nor creep so efficiently as do chydorids. So far as is known only one species, Macrothrix triseal , has evolved a chydorid-like method of crawling by means of the first trunk limbs but others have acquired means of locomotion peculiar to themselves. In only a few cases is the post-abdomen used for pushing, its lack of such employment and the lack of a joint between it and the trunk being primitive features. In basic structure and arrangement the trunk limbs are similar to those of the Chydoridae and the principles involved in many of the feeding mechanisms are the same in both families. By numerous, sometimes subtle, sometimes profound modifications of the components involved, this basic arrangement has been adapted to widely differing ways of life and different functions. Many macrothricids use the first trunk limbs for food collection rather than the second as in most chydorids. This is interpreted as a primitive feature. Acantholeberis curvirostris (figures 1-6), a frequenter of peaty pools, is primitive in several respects; for example, it lacks a headshield and is unable to push effectively with its post-abdomen, but exhibits several specializations. The antennae, which also serve as props and levers, are the principal means of locomotion, and have massive protopods flexed at about 90°. Progression is by means of intermittent ‘leaps’: steady swimming is not practised. Crawling by use of the first trunk limbs in a manner that foreshadows the efficient crawling of certain anomopods is feebly developed. Food collected by the first trunk limbs is dragged into the chamber made up by these and other trunk limbs (figures 8, 9), both mechanical handling and filtration being involved in its manipulation

Evolution and adaptive radiation in the Chydoridae (Crustacea: Cladocera): a study in comparative functional morphology and ecology

Considering the advanced state of our knowledge of the systematics of the freshwater cyclopoid copepods and the fact that many species are abundant in natural waters it is surprising that practically nothing is known of their food and feeding mechanisms. A few casual and often contradictory statements relating to the food of the group are to be found scattered through the literature but no definite study of the subject appears to have been made. Gurney's statement (1931) that 'it is most difficult to determine the food as it is generally impossible to recognize it from the contents of the gut' is too pessimistic, for by the employment of a very simple technique the nature of the gut contents can usually be revealed. The earliest references to the food of cyclopoids are to be found in writings dating back to the early years of the nineteenth century, but as Klugh (1927), who studied the feeding habits of certain freshwater crustaceans remarks 'the earlier writers on Entomostraca are extremely vague in their statements as to the food of these animals'. However, one of the earliest, Jurine (1820), made the observation, which seems to have been largely ignored by subsequent workers, that Cyclops is carnivorous. Birge (1897) (cited by Klugh 1927, and Gurney 1931) also claimed that Cyclops is partially carnivorous, eating rotifers, nauplii 'and other animals'. He also mentions a Cyclops, presumably a plankton species, feeding on Ceratium. Since these early days references to the food of cyclopoids have been made by Naumann (1918), Klugh (1927) and Vetter (1927a, b), though Vetter was interested in phytoplankton and its fate rather than in the food of cyclopoids. Neither he nor Naumann made specific determinations, a fact which robs their observations of much of their value, and neither added substantially to our knowledge. Klugh's work is still the most comprehensive review of the food of the freshwater Entomostraca, though he studied only two cyclopoid copepods-Macrocyclops fuscus and what would now be called Acanthocyclops bicuspidatus thomasi. The only food which he recorded from the gut of the latter species was the alga Chaetophora elegans, while from the gut of Macrocyclops fuscus he recorded 'palmella forms', a Chlamydomonas, and 'chitin fragments'. However, he also observed Macrocyclops fuscus seizing and partially devouring small specimens of its own species and of Diaptomus birgei. In addition a few casual statements from the literature deserve mention. Babaik (1913), cited by Oliva & Sladacek (1950), reports an attack on the larva of * Present address: East African Fisheries Research Organization, P.O. Box, 343, Jinja, Uganda.

The food of some freshwater cyclopoid copepods and its ecological significance.

The trophic interrelationships and ecology of some littoral communities of lake nyasa with especial reference to the fishes, and a discussion of the evolution of a group of rock-frequenting cichlidae

The introduction of the Nile perch into Lake Victoria, East Africa, has had disastrous consequences Fisheries have been not merely damaged but destroyed Lake Malawi has the world's most species-rich fish fauna and the prospect of introduction of alien species could mean disaster

Geoffrey Fryer

Papers

The Cichlid fishes of the Great Lakes of Africa.

Evolution and adaptive radiation in the Chydoridae (Crustacea: Cladocera): a study in comparative functional morphology and ecology

The food of some freshwater cyclopoid copepods and its ecological significance.

The trophic interrelationships and ecology of some littoral communities of lake nyasa with especial reference to the fishes, and a discussion of the evolution of a group of rock-frequenting cichlidae

Destruction of fisheries in Africa's lakes