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

Statistical method for testing the neutral mutation hypothesis by DNA polymorphism.

So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

An essential textbook for any student or researcher in biology needing to design experiments, sample programs or analyse the resulting data The text begins with a revision of estimation and hypothesis testing methods, covering both classical and Bayesian philosophies, before advancing to the analysis of linear and generalized linear models Topics covered include linear and logistic regression, simple and complex ANOVA models (for factorial, nested, block, split-plot and repeated measures and covariance designs), and log-linear models Multivariate techniques, including classification and ordination, are then introduced Special emphasis is placed on checking assumptions, exploratory data analysis and presentation of results The main analyses are illustrated with many examples from published papers and there is an extensive reference list to both the statistical and biological literature The book is supported by a website that provides all data sets, questions for each chapter and links to software

/pdf/experimental-design-and-data-analysis-for-biologists-8ybva8d53x.pdf

Experimental Design and Data Analysis for Biologists

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

Theory predicts a trade-off between current reproduction and future reproduction or survival. Nevertheless, costs of reproduction are often not found owing to heterogeneity in environment or individuals, or to studies not evaluating multiple costs or reproductive metrics that could influence costs. Detecting costs of reproduction is further complicated by the fact that they may increase with age if physiological condition declines in older individuals, or decrease with age if younger individuals are less efficient at acquiring resources than older individuals. We used a 37-year study to evaluate costs of reproduction in song sparrows (Melospiza melodia). Our results support theoretical expectations for short-lived species by demonstrating costs of reproduction on future survival, but not on future reproduction. We examined two metrics of reproductive allocation—reproductive effort and termination of breeding—and found that only higher reproductive effort increased costs. Thus, testing of multiple allocation metrics may be necessary because results may not be coincident between metrics. Lastly, we observed that younger females paid higher costs of reproduction than older females. Although older female sparrows senesced, they had lower costs of reproduction than younger females who may be less able to acquire food or high-quality mates. By taking into account variation among individuals and examining multiple metrics, our study provides strong support for costs of reproduction and a decrease in costs with age. One premise of life history theory is that reproduction is costly, but evidence of such costs remains mixed. Mixed results may arise because resources are not always limiting for all individuals or in all environments, leading to temporal, spatial, and individual heterogeneity in trade-offs between current reproduction and future reproduction or survival that can be hard to detect. Costs may also vary with age, depending on how resource acquisition and allocation vary with age. We used a 37-year study of female song sparrows (Melospiza melodia) to control statistically for individual and environmental heterogeneity and test multiple cost metrics. We demonstrate marked costs of reproduction on future survival, particularly in young females.

Young females pay higher costs of reproduction in a short-lived bird

Variation in immune gene sequences is known to influence resistance to infectious diseases and parasites, and hence survival and mate choice, across animal taxa. Toll-like receptors (TLRs) comprise one essential gene family in the vertebrate innate immune system and recognize evolutionarily conserved structures from all major microorganism classes. However, the causes and consequences of TLR variation in passerine birds remain largely unexplored. We examined 7 TLR genes in song sparrows (Melospiza melodia), a species that is studied across North America. We then examined sequences from 4 unduplicated TLRs (TLR1LB, TLR3, TLR4, and TLR15) from birds in 2 parts of the species' range (N = 27, N = 6), tested for evidence of selection, and conducted pilot analyses of the role of TLR heterozygosity in survival. We identified 45 SNPs: 19 caused changes in amino acid sequences and 2 of these were likely deleterious. We found no evidence of codon-level episodic positive selection but detected purifying selection at codons in all TLRs. Contrary to expectations we found no strong correlation between heterozygosity at TLRs and inbreeding coefficient f (estimate ± standard error [SE] = -0.68 ± 0.37, Radj2 = 0.08, F1,25 = 3.38, P = 0.08). In addition, pilot analyses revealed no relationship between TLR heterozygosity and survival (β ± SE: 0.09 ± 2.00, P = 0.96), possibly due to small sample size. Further analyses of genetic diversity in TLRs are likely to advance understanding of the effects of innate immune gene diversity on the fitness and persistence of wild populations.

Purifying Selection in the Toll-Like Receptors of Song Sparrows Melospiza melodia

Summary

This paper describes observations on body size, growth, and the timing of births in an individually identified population of oribi (Ourebia ourebi, Zimmermann 1783) in the Serengeti National Park, Tanzania. Females tended to be larger and approximately 2 kg heavier than males. Young oribi grew rapidly, attaining near-adult size in about 7 months. Horns appeared in male oribi at about 4½ months of age and grew rapidly up to 20 months of age. Births occurred in all months of the year but were most common between March and June. The results provide an observational means of estimating the age of sub-adult oribi by body size, and the age of adult male oribi, up to 20 months of age, by horn length.

Growth, size and the timing of births in an individually identified population of oribi

Why hire a behaviorist into a conservation or management team

Identifying factors that influence growth throughout development is important for understanding the consequences of variation in resource quality on recruitment. Marbled Murrelets (Brachyramphus marmoratus (J.F. Gmelin, 1789)) are threatened seabirds that are extremely cryptic in their nesting behaviour, which makes it challenging to understand how ju- veniles allocate resources during development. From a single capture at sea, we analyzed stable carbon isotopes in feathers and blood of juvenile murrelets to infer diet composition during both the pre- and the post-fledging periods. Consistent with the challenges juveniles face during their first year of life, we found that wing and bill growth were prioritized in the nest, whereas development of energy stores was delayed until after nest departure. We also found that diet quality after nest de- parture influenced bill size and body condition, two body components that continue to grow after independence. Our results provide evidence that murrelets strategically allocate resources according to their stage of development and that the availabil- ity of high-quality prey is likely to be important to juvenile development. These results identify a potential mechanism through which feeding conditions may influence reproduction of murrelets and demonstrate the utility of stable isotopes to examine the influence of diet quality on growth over multiple stages of development.

Stable isotopes reveal strategic allocation of resources during juvenile development in a cryptic and threatened seabird, the Marbled Murrelet (Brachyramphus marmoratus)

Peter Arcese

Papers

Young females pay higher costs of reproduction in a short-lived bird

Purifying Selection in the Toll-Like Receptors of Song Sparrows Melospiza melodia

Growth, size and the timing of births in an individually identified population of oribi

Why hire a behaviorist into a conservation or management team

Stable isotopes reveal strategic allocation of resources during juvenile development in a cryptic and threatened seabird, the Marbled Murrelet (Brachyramphus marmoratus)