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

Changes in climate extremes and their impacts on the natural physical environment: An overview of the IPCC SREX report

We provide a brief synopsis of the unique physical and ecological attributes of sandy beach ecosystems and review the main anthropogenic pressures acting on the world's single largest type of open shoreline. Threats to beaches arise from a range of stressors which span a spectrum of impact scales from localised effects (e.g. trampling) to a truly global reach (e.g. sea-level rise). These pressures act at multiple temporal and spatial scales, translating into ecological impacts that are manifested across several dimensions in time and space so that today almost every beach on every coastline is threatened by human activities. Press disturbances (whatever the impact source involved) are becoming increasingly common, operating on time scales of years to decades. However, long-term data sets that describe either the natural dynamics of beach systems or the human impacts on beaches are scarce and fragmentary. A top priority is to implement long-term field experiments and monitoring programmes that quantify the dynamics of key ecological attributes on sandy beaches. Because of the inertia associated with global climate change and human population growth, no realistic management scenario will alleviate these threats in the short term. The immediate priority is to avoid further development of coastal areas likely to be directly impacted by retreating shorelines. There is also scope for improvement in experimental design to better distinguish natural variability from anthropogenic impacts. Sea-level rise and other effects of global warming are expected to intensify other anthropogenic pressures, and could cause unprecedented ecological impacts. The definition of the relevant scales of analysis, which will vary according to the magnitude of the impact and the organisational level under analysis, and the recognition of a physical–biological coupling at different scales, should be included in approaches to quantify impacts. Zoning strategies and marine reserves, which have not been widely implemented in sandy beaches, could be a key tool for biodiversity conservation and should also facilitate spillover effects into adjacent beach habitats. Setback and zoning strategies need to be enforced through legislation, and all relevant stakeholders should be included in the design, implementation and institutionalisation of these initiatives. New perspectives for rational management of sandy beaches require paradigm shifts, by including not only basic ecosystem principles, but also incentives for effective governance and sharing of management roles between government and local stakeholders.

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Threats to sandy beach ecosystems: A review

Quaternary glaciations of the southern Andes

Why do ecologists seem to underestimate the consequences of using bad taxonomy? Is it because the consequences of doing so have not been yet scrutinized well enough? Is it because these consequences are irrelevant? In this paper I examine and discuss these questions, focusing on the fact that because ecological works provide baseline information for many other biological disciplines, they play a key role in spreading and magnifying the abundance of a variety of conceptual and methodological errors. Although overlooked and underestimated, this cascade-like process originates from trivial taxonomical problems that affect hypotheses and ideas, but it soon shifts into a profound practical problem affecting our knowledge about nature, as well as the ecosystem structure and functioning and the efficiency of human health care programs. In order to improve the intercommunication among disciplines, I propose a set of specific requirements that peer reviewed journals should request from all authors, and I also advocate for urgent institutional and financial support directed at reinvigorating the formation of scientific collections that integrate taxonomy and ecology.

Error Cascades in the Biological Sciences: The Unwanted Consequences of Using Bad Taxonomy in Ecology

Correlation and dating of Quaternary littoral zones along the Patagonian coast, Argentina

A large body of information exists on marsh foraminifera of North America but until now few quantitative studies had been done at corresponding latitudes in the southern hemisphere. To remedy this situation, we sampled six marshes along the eastern coast of South America from Tierra del Fuego (54°S) to Guaratuba, Brazil (25°S). The southernmost area corresponds in latitude to work done in Hudson-James Bay marshes and the South American material is almost identical to Hudson-James Bay with Polysaccammina ipohalina and Trochammina macrescens dominating. Marshes in between are more similar to the Californian marshes with Trochammina inflata dominating high marsh areas. In the Brazilian marsh, which is in the southernmost limit of mangroves, the fauna is similar to that found in the Mississippi Delta marshes, at approximately the same latitude north. Species here include Haplophragmoides wilberti and Arenoparrella mexicana. This study illustrates that marsh foraminifera do respond to latitudinal gradients in both hemispheres of the Americas.

Recent Marsh Foraminifera from the East Coast of South America: Comparison to the Northern Hemisphere

Five areas along the Patagonian coast, Argentina, were sampled for ESR age estimates in order to elucidate earlier conclusions on the number, characteristics, geomorphology, correlation and amino acid age estimates of Quaternary shorelines in Patagonia (Rutter et al ., 1989). Areas investigated include: San Blas, San Antonio Oeste, Caleta Valdes, Bahia Bustamante and Puerto Deseado. The ESR ages generally confirmed conclusions based on the amino acid data. The "oldest" shorelines are found at elevations between 24 and 41 m above mean sea level and are judged to represent the penultimate or older interglacial. The "intermediate" aged shorelines are present at some locations, represented by beach ridges varying between 20 and 28 m. These ridges were probably formed during the last interglacial (isotope stage 5e). Well defined "young" beach ridges between 8-12 m above mean sea level are found in most locations and have been 14 C dated and verified by amino acid and ESR dates as Holocene in age.

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Comparison of ESR and Amino Acid Data in Correlating and Dating Quaternary Shorelines Along the Patagonian Coast, Argentina

Positive storm surges (PSS) lasting for several days can raise the water level producing significant differences between the observed level and the astronomical tide. These storm events can be more severe if they coincide with a high tide or if they bracket several tidal cycles, particularly in the case of the highest astronomical tide. Besides, the abnormal sea-level elevation near the coast can cause the highest waves generated to attack the upper beach. This combination of factors can produce severe erosion, threatening sectors located along the coastline. These effects would be more serious if the storm surge height and duration increase as a result of a climatic change. The Mar del Plata (Argentina) coastline and adjacent areas are exposed to such effects. A statistical characterization of PSS based on their intensity, duration and frequency, including a surge event classification, was performed utilizing tide-gauge records over the period 1956–2005. A storm erosion potential index (SEPI) was calculated from observed levels based on hourly water level measurements. The index was related to beach profile responses to storm events. Also, a return period for extreme SEPI values was calculated. Results show an increase in the average number of positive storm surge events per decade. Considering all the events, the last decade (1996–2005) exhibits an average 7% increase compared to each one of the previous decades. A similar behavior was found for the decadal average of the heights of maximum annual positive storm surges. In this case the average height of the last two decades exceeds that of the previous decades by approximately 8 cm. The decadal average of maximum annual duration of these meteorological events shows an increase of 2 h in the last three decades. A possible explanation of the changes in frequency, height and duration of positive storm surges at Mar del Plata would seem to lie in the relative mean sea-level rise.

Enrique J. Schnack

Papers

Correlation and dating of Quaternary littoral zones along the Patagonian coast, Argentina

Recent Marsh Foraminifera from the East Coast of South America: Comparison to the Northern Hemisphere

Comparison of ESR and Amino Acid Data in Correlating and Dating Quaternary Shorelines Along the Patagonian Coast, Argentina

Storm surges and coastal impacts at Mar del Plata, Argentina

Estratigrafía del cuaternario marino tardío en la provincia de Buenos Aires