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

Hypothesis-testing methods for multivariate data are needed to make rigorous probability statements about the effects of factors and their interactions in experiments. Analysis of variance is particularly powerful for the analysis of univariate data. The traditional multivariate analogues, however, are too stringent in their assumptions for most ecological multivariate data sets. Non-parametric methods, based on permutation tests, are preferable. This paper describes a new non-parametric method for multivariate analysis of variance, after McArdle and Anderson (in press). It is given here, with several applications in ecology, to provide an alternative and perhaps more intuitive formulation for ANOVA (based on sums of squared distances) to complement the description pro- vided by McArdle and Anderson (in press) for the analysis of any linear model. It is an improvement on previous non-parametric methods because it allows a direct additive partitioning of variation for complex models. It does this while maintaining the flexibility and lack of formal assumptions of other non-parametric methods. The test- statistic is a multivariate analogue to Fisher's F-ratio and is calculated directly from any symmetric distance or dissimilarity matrix. P-values are then obtained using permutations. Some examples of the method are given for tests involving several factors, including factorial and hierarchical (nested) designs and tests of interactions.

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A new method for non-parametric multivariate analysis of variance

For centuries, biologists have studied patterns of plant and animal diversity at continental scales. Until recently, similar studies were impossible for microorganisms, arguably the most diverse and abundant group of organisms on Earth. Here, we present a continental-scale description of soil bacterial communities and the environmental factors influencing their biodiversity. We collected 98 soil samples from across North and South America and used a ribosomal DNA-fingerprinting method to compare bacterial community composition and diversity quantitatively across sites. Bacterial diversity was unrelated to site temperature, latitude, and other variables that typically predict plant and animal diversity, and community composition was largely independent of geographic distance. The diversity and richness of soil bacterial communities differed by ecosystem type, and these differences could largely be explained by soil pH (r(2) = 0.70 and r(2) = 0.58, respectively; P < 0.0001 in both cases). Bacterial diversity was highest in neutral soils and lower in acidic soils, with soils from the Peruvian Amazon the most acidic and least diverse in our study. Our results suggest that microbial biogeography is controlled primarily by edaphic variables and differs fundamentally from the biogeography of "macro" organisms.

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The diversity and biogeography of soil bacterial communities

Physiological and ecological constraints play key roles in the evolution of plant growth patterns, especially in relation to defenses against herbivores. Phenotypic and life history theories are unified within the growth-differentiation balance (GDB) framework, forming an integrated system of theories explaining and predicting patterns of plant defense and competitive interactions in ecological and evolutionary time. Plant activity at the cellular level can be classified as growth (cell division and enlargement) of differentiation (chemical and morphological changes leading to cell maturation and specialization). The GDB hypothesis of plant defense is premised upon a physiological trade-off between growth and differentiation processes. The trade-off between growth and defense exists because secondary metabolism and structural reinforcement are physiologically constrained in dividing and enlarging cells, and because they divert resources from the production of new leaf area. Hence the dilemma of plants: Th...

https://www.jstor.org/stable/pdfplus/2830650.pdf

The dilemma of plants: To grow or defend.

Identification of the selective forces on plant dispersal engenders theoretical argument, empirical study, and speculation. We separate evidence, testable hypotheses, and conjecture surrounding two major questions in dispersal ecology. The first asks what ecological, and ultimately evolutionary, advantages exist in seed dispersal. Astonishingly little is known about the advantages to a parent plant that are actually conferred by investment in dispersal structures. Does dispersal enable seeds and ultimately seedlings to escape mortality near the parent? Is continual recolonization of unstable habitats the primary advantage? Must seeds find rare microhabitats suitable for reestablishment? Such issues are addressed through joint consideration of dispersal and establishment-those stages both mediated by parental provisioning and subject to the highest mortality in the life of a plant. The second broad question asks what general and explicit environmental forces influence the timing and mode of dispersal. Do climates or seasons favor one dispersal mode over another? Do differences in number, size, morphology, or nutritional quality of fruits influence frugivore choice, and consequently differential dispersal of species or individuals within species? Studies of dispersal process and mode should be intimately connected. A general objective of this paper is to explore the degree to which they are integrated and, in so doing, to catalyze their union. We emphasize topics most in need of critical attention: the evolutionary ecology of dispersal process and mode. Excellent recent reviews consider such related topics as dispersal mechanism (131, 184), seed dormancy (1, 30), phytogeography (11, 115, 146), masting and predator satiation (105, 156), and succession (68, 69, 189).

https://www.jstor.org/stable/info/2097067

Ecology of Seed Dispersal

Aspects of the incidence and spread of the citrus disease huanglongbing (HLB) in relation to the vector Diaphorina citri population fluctuation were studied from January 1999 to December 2001 seasons in a 0.8 ha citrus orchard at Jemukan (1° 33'N, 110° 41'E), Southwest Sarawak in Malaysia. In relation to insecticide and horticultural mineral oils (HMOs) use, levels of HLB infection rose quite rapidly over the next 3 years in the unsprayed control and less rapidly in the other treatments such as imidacloprid, nC24HMO, and triazophos/cypermethrin/chlorpyrifos. Levels of HLB as determined by Polymerase Chain Reaction (PCR) were 42.2%, 9.4%, 11.4%, and 22.7%, respectively. The effects of nC(24)HMO and conventional pesticides on the citrus psyllid population and parasitoids in citrus orchard were also determined.

/pdf/impacts-of-horticultural-mineral-oils-and-two-insecticide-3ff8zaunlj.pdf

Impacts of horticultural mineral oils and two insecticide practices on population fluctuation of Diaphorina citri and spread of Huanglongbing in a citrus orchard in Sarawak.

In the dry eucalypt forests of north-eastern New South Wales, Australia, cattle grazing occurs at low intensities and is accompanied by frequent low-intensity burning. This study investigated the combined effects of this management practice on the ground-dwelling and arboreal (low vegetation) spider assemblages. Spiders were sampled at 49 sites representing a range of grazing intensities, using pitfall trapping, litter extraction and sweep sampling. A total of 237 spider morphospecies from 37 families were collected using this composite sampling strategy. The abundance, richness, composition and structure of spider assemblages in grazed and ungrazed forest sites were compared and related to a range of environmental variables. Spider assemblages responded to a range of environmental factors at the landscape, habitat and microhabitat scales. Forest type, spatial relationships and habitat variability at the site scale were more important in determining spider assemblages than localized low-intensity grazing and burning. However, it is possible that a threshold intensity of grazing may exist, above which spiders respond to grazing and burning. Although low-intensity grazing and burning may not affect spider assemblages below a threshold stocking rate, that stocking rate has yet to be established.

Impacts of grazing and burning on spider assemblages in dry eucalypt forests of north-eastern New South Wales, Australia

The evolution of ant pollination systems

We examined the taxonomic and structural concordance between oribatid mite communities at different sites from around the world using meta-analysis. The study explored similarities in the taxonomie composition and species abundance distributions among oribatid mite communities using 25 published species lists from Africa, Australia, Europe. Japan. Malaysia, New Zealand and the United States, The final data set contained 253 genera from 97 families in 43 superfamilies, A second data set, which included only studies where trees were present at the sites, contained 234 genera, 93 families and 41 superfamilies. Composition was analysed at taxonomic levels higher than species. Only two families and four superfamilies were present in > 90% of all studies. Two genera, six families and seven superfamilies were found in all sites with trees. Common families were different among habitats suggesting that habitat preferences may be expressed at the family level. There were very strong relationships between oribatid mite species richness and richness at higher taxonomic levels with r2 values for regression relationships > 0.8. Few species at a site were from the same genus, family or superfamily. Species abundance distributions were remarkably consistent between studies with the three most dominant species each constituting > 10% of the oribatid individuals. Overall, similar factors may determine the relative proportions of soil-dwelling oribatid species at a site.

Taxonomic and structural similarities in soil oribatid communities

A series of spatially nested assemblages of Rhytidoponera operational taxonomic units (OTUs) (Formicidae: Hymenoptera) from Sturt National Park, New South Wales, Australia, were examined for patterns of dispersion in multivariate morphological space. Morphological overdispersion within an assemblage, relative to a null model, is hypothesized to be a result of the structuring influence of interspecific competition. We compared up to 45 observed assemblages, from across multiple spatial scales, to two null models. Meta-analysis of the null model analyses indicated a general trend to morphological overdispersion, particularly so at restricted scales. Larger scale assemblages were overdispersed relative to only one of the two null models, which we tentatively interpret as being indicative of different competition-driven mechanisms operating at different spatial scales. We also demonstrate that the observed assemblages represent a larger number of species groups than expected by chance, and that this pattern of phylogenetic overdispersion is closely related to the observed morphological patterns.

Andrew J. Beattie

Papers

Impacts of horticultural mineral oils and two insecticide practices on population fluctuation of Diaphorina citri and spread of Huanglongbing in a citrus orchard in Sarawak.

Impacts of grazing and burning on spider assemblages in dry eucalypt forests of north-eastern New South Wales, Australia

The evolution of ant pollination systems

Taxonomic and structural similarities in soil oribatid communities

Morphological dispersion of rhytidoponera assemblages: the importance of spatial scale and null model