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

Statistics for Spatial Data.

Genetics and analysis of quantitative traits

Climate change 2014 - Synthesis Report

Recent studies suggest that populations and species often exhibit behavioral syndromes; that is, suites of correlated behaviors across situations. An example is an aggression syndrome where some individuals are more aggressive, whereas others are less aggressive across a range of situations and contexts. The existence of behavioral syndromes focuses the attention of behavioral ecologists on limited (less than optimal) behavioral plasticity and behavioral carryovers across situations, rather than on optimal plasticity in each isolated situation. Behavioral syndromes can explain behaviors that appear strikingly non-adaptive in an isolated context (e.g. inappropriately high activity when predators are present, or excessive sexual cannibalism). Behavioral syndromes can also help to explain the maintenance of individual variation in behavioral types, a phenomenon that is ubiquitous, but often ignored. Recent studies suggest that the behavioral type of an individual, population or species can have important ecological and evolutionary implications, including major effects on species distributions, on the relative tendencies of species to be invasive or to respond well to environmental change, and on speciation rates. Although most studies of behavioral syndromes to date have focused on a few organisms, mainly in the laboratory, further work on other species, particularly in the field, should yield numerous new insights.

/pdf/behavioral-syndromes-an-ecological-and-evolutionary-overview-53ct6xj1u3.pdf

Behavioral syndromes: an ecological and evolutionary overview.

The population stability and home ranges of rock doves (Columba livia var) were investigated by means of surveys and monitoring of marked individuals We also studied the population response to re

Urban pigeon populations: stability, home range, and the effect of removing individuals

Central in invasion biology is to understand why alien species, whose initial populations are generally small and genetically depleted, can succeed to establish themselves in environments to which they have had no opportunity to adapt (Sax and Brown 2000). This paradox is usually resolved by invoking pre-adaptations of non-indigenous species to novel environments. The idea is that some species are successful invaders because they have attributes that pre-adapt them to survive and reproduce in novel environments (Mayr 1965). However, do we really have evidence that there exist properties of successful invaders? The goal of this chapter is to evaluate to what extent establishment success of terrestrial vertebrates may be understood by the existence of pre-adaptations of species to novel environments. This implies answering two interrelated questions: (1) do species differ in their invasion potential? And if so, (2) what are the features of the species that identify some as successful invaders? Answering these questions is important not only to fully understand how animals respond to new environmental conditions, but also to help identify and prevent situations where the risk is high that a species becomes established and causes ecological impact when introduced in a novel region.

Do Successful Invaders Exist? Pre-Adaptations to Novel Environments in Terrestrial Vertebrates

Despite the central importance of the niche concept for the ecological theory, current methods to quantify the species niche from qualitative resources, such as food or habitat types, remain insufficiently developed. Classically, information theory and diversity measures have formed the toolbox used for calculating resource niche metrics on species preference data for a set of qualitative resources. We provide a comprehensive framework that extends these classical approaches by incorporating the resemblance between resources into the calculation of resource niche metrics. This does not only allow estimation of the niche centre, breadth, overlap and displacement with greater accuracy, but also makes the estimates less influenced by the way the resources are subdivided. In addition, all niche metrics can be calculated while taking into account the variation in resource availability, and confidence intervals can be obtained by bootstrapping. We illustrate the utility of the framework with an analysis of dietary preferences in feral pigeons Columba livia.

/pdf/a-framework-for-estimating-niche-metrics-using-the-2yi1dt89yc.pdf

A framework for estimating niche metrics using the resemblance between qualitative resources

Despite growing appreciation of the importance of considering a pace-of-life syndrome (POLS) perspective to understand how animals interact with their environment, studies relating behavior to life history under altered environmental conditions are still rare. By means of a comparative analysis of flight initiation distances (i.e., the distance at which an animal takes flight when a human being is approaching) across > 300 bird species distributed worldwide, we document here the existence of a POLS predicted by theory where slow-lived species tend to be more risk-averse than fast-lived species. This syndrome largely emerges from the influence of body mass, and is highly dependent on the environmental context. Accordingly, the POLS structure vanishes in urbanized environments due to slow-lived species adjusting their flight distances based on the perception of risk. While it is unclear whether changes in POLS reflect plastic and/or evolutionary adjustments, our findings highlight the need to integrate behavior into life history theory to fully understand how animals tolerate human-induced environmental changes. Animals can often respond to changing environmental conditions by adjusting their behavior. However, the degree to which different species can modify their behavior depends on their life history strategy and on the environmental context. Species-specific perception of risk is a conspicuous example of adjustable behavior tightly associated with life history strategy. While there is a general tendency of higher risk aversion in rural than city-dwelling birds, it is dependent on the species’ life history strategy. Slow-lived species are more prone to adjust their flight initiation distances based on the perception of risk, allowing humans to approach closer in urban than rural environments. Behavior must therefore be taken into account together with life history to reliably assess species’ vulnerability at the face of ongoing environmental change.

Risk-taking behavior, urbanization and the pace of life in birds

Island communities are generally viewed as being more susceptible to invasion than those of mainland areas, yet empirical evidence is almost lacking. A species-by-species examination of introduced birds in two independent island-mainland comparisons is not consistent with this hypothesis. In the New Zealand-mainland Australia comparison, 16 species were successful in both regions, 19 always failed and only eight had mixed outcomes. Mixed results were observed less often than expected by chance, and in only 5 cases was the relationship in the predicted direction. This result is not biased by differences in introduction effort because, within species, the number of individuals released in New Zealand did not differ significantly from those released in mainland Australia. A similar result emerged in the Hawaiian islands-mainland USA comparison: among the 35 species considered, 15 were successful in both regions, seven always failed and 13 had mixed outcomes. In this occasion, the results fit well to those expected by chance, and in only seven cases was the relationship in the direction predicted. I therefore conclude that, if true, the view that islands are less resistant than continents to invasions is far from universal.

/pdf/are-islands-more-susceptible-to-be-invaded-than-continents-xr32aexv4z.pdf

Daniel Sol

Papers

Urban pigeon populations: stability, home range, and the effect of removing individuals

Do Successful Invaders Exist? Pre-Adaptations to Novel Environments in Terrestrial Vertebrates

A framework for estimating niche metrics using the resemblance between qualitative resources

Risk-taking behavior, urbanization and the pace of life in birds

Are islands more susceptible to be invaded than continents? Birds say no