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

The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. 
The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. 
The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. 
The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

Influence of Diet On the Distribtion of Nitrogen Isotopes in Animals

Pollinators are a key component of global biodiversity, providing vital ecosystem services to crops and wild plants. There is clear evidence of recent declines in both wild and domesticated pollinators, and parallel declines in the plants that rely upon them. Here we describe the nature and extent of reported declines, and review the potential drivers of pollinator loss, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them. Pollinator declines can result in loss of pollination services which have important negative ecological and economic impacts that could significantly affect the maintenance of wild plant diversity, wider ecosystem stability, crop production, food security and human welfare.

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Global pollinator declines: trends, impacts and drivers.

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

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Climate Change 2007: The Physical Science Basis.

The world’s population is concentrated in urban areas. This change in demography has brought landscape transformations that have a number of documented effects on stream ecosystems. The most consistent and pervasive effect is an increase in impervious surface cover within urban catchments, which alters the hydrology and geomorphology of streams. This results in predictable changes in stream habitat. In addition to imperviousness, runoff from urbanized surfaces as well as municipal and industrial discharges result in increased loading of nutrients, metals, pesticides, and other contaminants to streams. These changes result in consistent declines in the richness of algal, invertebrate, and fish communities in urban streams. Although understudied in urban streams, ecosystem processes are also affected by urbanization. Urban streams represent opportunities for ecologists interested in studying disturbance and contributing to more effective landscape management.

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Streams in the Urban Landscape

. This paper reports what we believe to be the first record of allogromiid foraminifers from coastal Indian waters. Two species from the Vellar Estuary on the east coast of India south of Madras are described and placed in a new genus Vellaria. The foraminifers live at or near the sediment-water interface and are characterised by the development of a flared, conical or trumpet-shaped apertural structure which apparently serves to attach the test to small sand grains. Allogromiids are delicate and inconspicuous organisms which may be more widespread in esturine and brackish water settings than is currently realised.

https://jm.copernicus.org/articles/11/233/1992/jm-11-233-1992.pdf

A New Allogromiid Genus (Rhizopoda: Foraminiferida) from the Vellar Estuary, Bay of Bengal

We describe two new species of spherical single-chambered ('saccamminid') foraminifera from the bathyal and abyssal Weddell Sea (Southern Ocean), collected in epibenthic sledge and Agassiz trawl samples obtained during the 2005 ANDEEP III campaign. Both are assigned to Leptammina gen. nov. The new genus is similar in overall test morphology to Saccammina Carpenter, 1869; it is distinguished mainly by its test wall, which is delicate, flexible and composed of fine mineral grains, rather than being rigid and coarsely agglutinated. In Leptammina grisea gen. et sp. nov., the test wall is relatively thick, grayish with a violet tinge and a dull surface; the cytoplasm is dark greenish. In Leptammina flavofusca gen. et sp. nov., the test is yellowish brown, with a very finely, almost transluscent agglutinated wall; the cytoplasm is pale yellowish. Both species have prominent circular apertures. Maximum likelihood phylogenetic analysis of SSU rRNA gene data showed that both species group together with an undescribed shallow-water Antarctic species (“silver saccamminid”) in a very strongly supported clade (100 %). Leptammina grisea gen. et sp. nov. is a relatively uncommon species (29 specimens from 3 stations), found at 1580–4822 m depth in the central and north–western Weddell Sea; Leptammina flavofusca gen. et sp. nov. is common (398 specimens from 4 stations) at depths of 3138–4795 m in the central Weddell Sea and off Kapp Norvegia. Both species are presently known only from ANDEEP III samples.

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A new genus and two new species of saccamminid foraminiferans (Protista, Rhizaria) from the deep Southern Ocean*

Five new species and two new genera of xenophyophores (Foraminifera: Rhizaria) from part of the abyssal equatorial Pacific licensed for polymetallic nodule exploration

The ecology, distribution and mode of life of three species of surface-dwelling enteropneusts is described, based on ROV observations and samples on the flanks of the Northern Mid-Atlantic Ridge (MAR) at comparative stations north and south of the Sub-Polar Front. Tergivelum cinnabarinum was most abundant in the north (mean=4.56 ind. 1000 m−2±3.50 s.d.) and occurred at low densities in the south (mean=1.19±1.68 s.d.). Yoda purpurata was dominant in the south (mean=17.00 ind. 1000 m−2±12.32 s.d.) but only one individual was found in the north. The within-station distribution of all enteropneust species encountered was generally random. T. cinnabarinum was larger (mean total length 142 mm) than Y. purpurata (mean total length 70 mm). Size distributions suggested smaller individuals of both species on the western side of the MAR. Size and density of enteropneusts were generally higher in areas with higher carbon flux to the seafloor. A single individual of Allapasus isidis was observed drifting and settling to the seafloor at the SW site. Traces on the seafloor made by T. cinnabarinum covered a much higher percentage of the total seabed area surveyed (mean=0.323%±0.155 s.d.) than those of Y. purpurata (mean=0.034%±0.037 s.d.). Stable isotope values for T. cinnabarinum suggested that it was a typical surficial deposit feeder. Enteropneusts appear to be abundant and an important bioturbator on the sedimented seafloor of the MAR at around 2500 m depth.

Andrew J. Gooday

Papers

A New Allogromiid Genus (Rhizopoda: Foraminiferida) from the Vellar Estuary, Bay of Bengal

A new genus and two new species of saccamminid foraminiferans (Protista, Rhizaria) from the deep Southern Ocean*

Five new species and two new genera of xenophyophores (Foraminifera: Rhizaria) from part of the abyssal equatorial Pacific licensed for polymetallic nodule exploration

Deep-sea surface-dwelling enteropneusts from the Mid-Atlantic Ridge: Their ecology, distribution and mode of life

Xenophyophores (Protista) including two new species, from two abyssal sites in the Northeast Atlantic Ocean