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

Thereisgrowinginterestinthepossiblehealththreatposedbyendocrine-disruptingchemicals (EDCs), which are substances in our environment, food, and consumer products that interfere with hormone biosynthesis, metabolism, or action resulting in a deviation from normal homeostatic control or reproduction. In this first Scientific Statement of The Endocrine Society, we present the evidence that endocrine disruptors have effects on male and female reproduction, breast development and cancer, prostate cancer, neuroendocrinology, thyroid, metabolism and obesity, and cardiovascular endocrinology. Results from animal models, human clinical observations, and epidemiological studies converge to implicate EDCs as a significant concern to public health. The mechanisms of EDCs involve divergent pathways including (but not limited to) estrogenic, antiandrogenic, thyroid, peroxisome proliferator-activated receptor , retinoid, and actions through other nuclear receptors; steroidogenic enzymes; neurotransmitter receptors and systems; and many other pathways that are highly conserved in wildlife and humans, and which can be modeled in laboratory in vitro and in vivo models. Furthermore, EDCs represent a broad class of molecules such as organochlorinated pesticides and industrial chemicals, plastics and plasticizers, fuels, and many other chemicals that are present in the environment or are in widespread use. We make a number of recommendations to increase understanding of effects of EDCs, including enhancing increased basic and clinical research, invoking the precautionary principle, and advocating involvement of individual and scientific society stakeholders in communicating and implementing changes in public policy and awareness. (Endocrine Reviews 30: 293–342, 2009)

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Endocrine-Disrupting Chemicals: An Endocrine Society Scientific Statement

For decades, studies of endocrine-disrupting chemicals (EDCs) have challenged traditional concepts in toxicology, in particular the dogma of “the dose makes the poison,” because EDCs can have effects at low doses that are not predicted by effects at higher doses. Here, we review two major concepts in EDC studies: low dose and nonmonotonicity. Low-dose effects were defined by the National Toxicology Program as those that occur in the range of human exposures or effects observed at doses below those used for traditional toxicological studies. We review the mechanistic data for low-dose effects and use a weight-of-evidence approach to analyze five examples from the EDC literature. Additionally, we explore nonmonotonic dose-response curves, defined as a nonlinear relationship between dose and effect where the slope of the curve changes sign somewhere within the range of doses examined. We provide a detailed discussion of the mechanisms responsible for generating these phenomena, plus hundreds of examples from...

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Hormones and endocrine-disrupting chemicals: Low-dose effects and nonmonotonic dose responses

Human exposure to bisphenol A (BPA).

Plastics have transformed everyday life; usage is increasing and annual production is likely to exceed 300 million tonnes by 2010. In this concluding paper to the Theme Issue on Plastics, the Environment and Human Health, we synthesize current understanding of the benefits and concerns surrounding the use of plastics and look to future priorities, challenges and opportunities. It is evident that plastics bring many societal benefits and offer future technological and medical advances. However, concerns about usage and disposal are diverse and include accumulation of waste in landfills and in natural habitats, physical problems for wildlife resulting from ingestion or entanglement in plastic, the leaching of chemicals from plastic products and the potential for plastics to transfer chemicals to wildlife and humans. However, perhaps the most important overriding concern, which is implicit throughout this volume, is that our current usage is not sustainable. Around 4 per cent of world oil production is used as a feedstock to make plastics and a similar amount is used as energy in the process. Yet over a third of current production is used to make items of packaging, which are then rapidly discarded. Given our declining reserves of fossil fuels, and finite capacity for disposal of waste to landfill, this linear use of hydrocarbons, via packaging and other short-lived applications of plastic, is simply not sustainable. There are solutions, including material reduction, design for end-of-life recyclability, increased recycling capacity, development of bio-based feedstocks, strategies to reduce littering, the application of green chemistry life-cycle analyses and revised risk assessment approaches. Such measures will be most effective through the combined actions of the public, industry, scientists and policymakers. There is some urgency, as the quantity of plastics produced in the first 10 years of the current century is likely to approach the quantity produced in the entire century that preceded.

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Plastics, the environment and human health: current consensus and future trends.

Publisher Summary This chapter discusses on the empirical and theoretical information on the pheromones, which accelerate and delay puberty in the house mouse. The difficulty of this task and a desire for brevity contrive to guarantee omissions in this work. Life-history theory provides a rich backdrop against which to study the function of primer pheromones in house mice and for understanding primer pheromone function in general. It is well established that chemical cues from conspecifics alter the timetable of puberty in the young of many species. This cueing system, at least regarding the delay of puberty seems to serve the signal recipients, while the signal senders are little affected. Unwitting release of metabolic correlates of physiological state rather than altruism may explain the presence of the delay pheromone. The benefits gained by the recipients of the puberty pheromones are most easily understood in terms of their life history. Life history provides predictions of the environmental circumstances, social or otherwise, favoring early or delayed maturity.

The Physiology and Ecology of Puberty Modulation by Primer Pheromones

Social cues, often in the form of priming pheromones, can retard or enhance the rate of sexual development in a variety of mammals. The complex interactions between the social environment and reproduction have been explored most thoroughly in the house mouse. A urinary pheromone produced by females in a group inhibits sexual development, and a urinary pheromone from adult males accelerates onset of puberty in juvenile females. These priming pheromones apparently are detected by the vomeronasal organ and induce the changes in ovarian function via changes in the hypothalamic-pituitary system. Accelerated onset of puberty is not accompanied by deficits in reproductive performance. Puberty acceleration can have important management implications for domestic farm animals. It already is proving useful for manipulation in rearing swine and in synchronizing seasonal reproductive recrudescence in sheep. In cattle, the results are less clear that signals from the bull can hasten onset of puberty in heifers. The effect may be operable only under certain nutritional or other interacting conditions. Presumably, the postpartum anestrus period in the cow can be shortened by stimulation from the bull, although pheromones have not been implicated in this effect.

Coordination of social signals and ovarian function during sexual development.

Perinatal exposure to endocrine disrupting compounds alters behavior and brain in the female pine vole

Prenatal hormone exposure and sexual variation

Pine voles are assumed to be cooperative breeders that live in extended families. We applied DNA fingerprinting techniques using restriction enzyme Alu I and Jeffrey's probe 33.15 to wild-caught pine voles to estimate relatedness among individuals in social groups. Background band-sharing between unrelated individuals revealed a high degree of genetic variation ( X BS ± SD = 0.28 ± 0.09). Band-sharing values that range from 0.47 ± 0.20 to 0.60 ± 0.12 from putative groups suggest that groups form from simple nuclear families that may contain some unrelated individuals. In two of the five groups, band-sharing values suggest that offspring from previous litters remain philopatric beyond weaning, while parents produce successive litters. Furthermore, within-group band-sharing values are consistent with a monogamous mating system. This study provides preliminary genetic evidence concerning the degree of relatedness among individuals within groups of pine voles in an orchard habitat.

John G. Vandenbergh

Papers

The Physiology and Ecology of Puberty Modulation by Primer Pheromones

Coordination of social signals and ovarian function during sexual development.

Perinatal exposure to endocrine disrupting compounds alters behavior and brain in the female pine vole

Prenatal hormone exposure and sexual variation

Using DNA Fingerprinting to Estimate Relatedness within Social Groups of Pine Voles