Life history biology sits on the interface between genetics and ecology, and both have made important theoretical and empirical contributions to our understanding. However, the connections between the disciplines have not always been as close as they might have been and this book takes some useful steps towards remedying this. It gives an excellent review of life history theory, and integrates this well with results from the empirical literature. After an 11-page introduction, Roff sets out ‘a framework for analysis’ in which he covers the necessary elements of quantitative and population genetics. This includes clear definitions of fitness in a range of circumstances, from density independent populations in constant environments through to the more complex situations of density and frequency dependence and environments that are spatially or temporally stochastic. Trade-offs are then examined, including a valuable analysis of potential pitfalls in studying them and ways that these can be avoided. The author then deals in turn with evolution in constant environments; stochastic environments and ‘predictable environments’. The last of these covers situations where there is environmental variation, but at least some information is available to allow individuals to make an adaptive response. The final chapter identifies 20 topics for future study. Some will find the book too dominated by theory. Others (but probably not readers of Heredity!) will find it contains too much genetics. But Roff does an excellent job of making the theory accessible, covering the essential issues and pointing to original sources for the details. Theory is related to a significant number of empirical studies, although there is room for another book reviewing the empirical literature on life histories in detail, and Roff’s book would provide a robust skeleton on which to hang this. To make my own assessment, I examined in detail Roff’s discussion of the question of fitness measures for density dependent populations in stochastic environments – an area in which I have been involved. I could not fault him – all the key references were there and the issues were made very clear without the more esoteric mathematics. I also examined some areas that I was less familiar with, and again the text was clear and easy to read. My only real criticism of the book would be that its very long chapters (more than 130 pages in one case) makes it difficult to find things. It would have been simple to address this by including the section headings on the contents pages. A minor personal quibble would be that the book usually expresses problems in terms of the intrinsic rate of increase, r, and the characteristic (Lotka) equation. A matrix formulation is often more tractable and is easier to generalise to density dependent populations and stochastic environments, so expanding on the relationship between the two would have been useful. But overall this is an excellent book. It brings together the key theory in a single place. It gives an invaluable route into the literature, with a bibliography of 1600 or so items. These features, and its identification of topics that need further study should make an important contribution to moving the field forward.

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Life History Evolution

Island Biogeography; ecology, evolution, and conservation

Aim Temperature influences most components of animal ecology and life history ‐ but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location World-wide. Methods We used a large (861 species) global dataset of lizard body temperatures,and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures.We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity.

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Are lizards feeling the heat? A tale of ecology and evolution under two temperatures

Laurence M. Klauber's magnum opus, Rattlesnakes , was first published in 1956. The second edition of this classical study of rattlesnakes contains much new material and the references have been brought up-to-date. This is the most outstanding book ever published about rattlesnakes. Indeed, few books about animals of medical importance contain the breadth or depth of knowledge about the subject found in Klauber's book. Rattlesnakes is a book that should appeal to physicians who treat venomous snakebites, to amateur and professional herpetologists, to nature lovers, and to researchers who work with animal venoms. There is a detailed discussion of rattlesnakes' fangs, venom glands, and venoms, as well as an account of the ecological distribution of rattlesnakes, snakebite statistics, the symptoms and aftereffects of the bite, and snakebite treatment. It is unfortunate that recent references about snakebite treatment were not incorporated into the text of the book, owing to Mr. Klauber's untimely

Rattlesnakes: Their Habits, Life Histories, and Influence on Mankind

To safeguard the sustainable use of ecosystems and their services, early detection of potentially damaging changes in functional capabilities is needed. To support a proper ecosystem management, the analysis of an ecosystem’s vulnerability provide information on its weaknesses as well as on its capacity to recover after suffering an impact. However, the application of the vulnerability concept to ecosystems is still an emerging topic. After providing background on the vulnerability concept, we summarize existing ecosystem vulnerability research on the basis of a systematic literature review with a special focus on ecosystem type, disciplinary background, and more detailed definition of the ecosystem vulnerability components. Using the Web of ScienceTM Core Collection, we overviewed the literature from 1991 onwards but used the 5 years from 2011 to 2015 for an in-depth analysis, including 129 articles. We found that ecosystem vulnerability analysis has been applied most notably in conservation biology, climate change research, and ecological risk assessments, pinpointing a limited spreading across the environmental sciences. It occurred primarily within marine and freshwater ecosystems. To avoid confusion, we recommend using the unambiguous term ecosystem vulnerability rather than ecological, environmental, population, or community vulnerability. Further, common ground has been identified, on which to define the ecosystem vulnerability components exposure, sensitivity, and adaptive capacity. We propose a framework for ecosystem assessments that coherently connects the concepts of vulnerability, resilience, and adaptability as different ecosystem responses. A short outlook on the possible operationalization of the concept by ecosystem vulnerabilty indices, and a conclusion section complete the review.

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Ecosystem Vulnerability Review: Proposal of an Interdisciplinary Ecosystem Assessment Approach

We studied the reproductive cycle of Sceloporus grammicus from two localities in Hidalgo, Mexico: La Estanzuela (LE) and Tilcuautla (TIL) of the Municipality of Mineral del Chico and San Agustin Tlaxiaca, respectively. Males were larger than females in both populations, with males having larger snout–vent lengths (SVLs), heads, and limbs than females. Males from LE reached sexual maturity at a larger SVL (42.2 mm) than males from TIL (38.9 mm). Females from LE reached sexual maturity at a smaller SVL (41.6 mm) than females from TIL (44.6 mm). Reproductive activity of both sexes from both populations was asynchronous. Testicular recrudescence at LE occurred May–July, reaching maximum activity August–October, and showing regression November–December, whereas in TIL, recrudescence occurred May–June, reaching maximum activity July–October, and showing regression November–December. Vitellogenesis occurred May–October in both populations, with ovulation occurring November–December. Embryonic developmen...

Reproduction and sexual dimorphism in two populations of Sceloporus grammicus (Sauria: Phrynosomatidae) from Hidalgo, Mexico

Ram�irez-Bautista, A., Stephenson, B.P., Serrano Mu~ C., Cruz-Elizalde, R. and HernU. 2014. Reproduction and sexual dimorphism in two populations of the polymorphic spiny lizard Sceloporus minor from Hidalgo, M� — Acta Zoologica (Stockholm) 95: 397-408. Male-biased sexual dimorphism is extensive in New World spiny lizards (Scelopo- rus: Phrynosomatidae) and is particularly prominent in the polymorphic minor lizard Sceloporus minor. However, the possible relationship between patterns of sexual dimorphism and gonadal development is little known for most species. In this study, we explored aspects of sexual dimorphism in noncolor morphological traits in S. minor and characterized the gonadal cycle in males and females from each of two sites (El Enzuelado and La Manzana) in Hidalgo, Mdiffering in key ecological aspects linked to life-history trait expression in other lizards. Males were generally larger than females in each population and expressed larger forms of several other morphological traits, although not all comparisons attained statistical significance. Both sexes attained reproductive maturity at a larger size in El Enzuelado relative to La Manzana, and females from El Enzue- lado had larger litters. Gonadal cycles differed substantially between the two populations and suggest that reproductive activity of males and females was synchronous at El Enzuelado and asynchronous at La Manzana, an unusual pattern. Geographic variation in sex-specific responses to environmental vari- ables may be at least partly responsible for the exceptional species diversity of spiny lizards in M�

Reproduction and sexual dimorphism in two populations of the polymorphic spiny lizard Sceloporus minor from Hidalgo, México

The Barranca de Metztitlan Biosphere Reserve (BMBR) is an extensive protected area (96 042.94 ha) in Hidalgo state of central Mexico. The reserve is well known for its globally significant endemic flora, but relatively little information is available regarding its herpetofauna. We examined reptile and amphibian community biodiversity occurring in each of 4 vegetation types characteristic of the reserve: pine-oak forest, tropical deciduous forest, sub-montane shrubland, and arid tropical scrubland. Field work was carried out between June 2006 and August 2007, a period spanning both wet and dry seasons. Overall, we found 7 species of amphibians and 31 species of reptiles in the BMBR, distributed in 14 families and 29 genera. Across all vegetation types, reptile species richness was greater in the rainy season, whereas amphibian species richness was greater in the dry season. Among vegetation types, tropical deciduous forest exhibited the highest diversity and richness of amphibians and reptiles. Pine-oak forest exhibited greatest species evenness and species diversity than the other vegetation types. Arid tropical scrubland and sub-montane shrubland were more similar to each other in species diversity. This study represents a significant addition to our knowledge of the herpetofauna from the BMBR, and an important base for future studies on the natural history of amphibians and reptiles in this reserve.

http://www.scielo.org.mx/pdf/rmbiodiv/v81n2/v81n2a20.pdf

Diversidad de anfibios y reptiles de la Reserva de la Biosfera Barranca de Metztitlán, Hidalgo, México

Body size exerts a strong influence on the physiology, morphology, ecology, and evolution of other life history traits in vertebrates. We compared the morphometry and allometry of two lizard species (Anolis nebulosus and Aspidoscelis lineattissima) occurring on mainland and island populations on the Pacific Coast of Mexico in order to understand the effect of an insular environment on body size and other morphometric structures. Results showed that both males and females of A. nebulosus from San Pancho Island were larger in body size than those from the mainland. Moreover, males of A. lineattissima from Cocinas Island exhibited larger forms of most measured morphometric traits than those from the mainland, whereas females from both island and mainland populations did not differ in body size or in other morphometric traits analyzed. Multivariate allometric coefficients of males and females of A. nebulosus from island and mainland populations showed a lower percentage of positive allometries than in A. lineattissima, probably because the former species is highly sedentary. Island populations of both species exhibit male-biased sexual dimorphisms in body size and size-adjusted morphometric traits. In contrast to the mainland population, morphometric comparisons of body size-adjusted traits showed that male A. lineattissima were larger than females only in head length, head width, forearm length, and tibia length, whereas in A. nebulosus, sexual dimorphism was observed just in HL. This study supports the hypothesis (island rule) that vertebrates on islands are larger than those of conspecifics on the mainland. In addition, sexual dimorphism observed between males and females of both species and populations could be associated with allometric growth (positive or negative) from some morphometric structures, as well as differences in the growth rates of these organisms.

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Uriel Hernández-Salinas

Papers

Reproduction and sexual dimorphism in two populations of Sceloporus grammicus (Sauria: Phrynosomatidae) from Hidalgo, Mexico

Reproduction and sexual dimorphism in two populations of the polymorphic spiny lizard Sceloporus minor from Hidalgo, México

Diversidad de anfibios y reptiles de la Reserva de la Biosfera Barranca de Metztitlán, Hidalgo, México

Morphometric variation in island and mainland populations of two lizard species from the Pacific Coast of Mexico

Amphibian species richness and diversity in a modified tropical environment of central Mexico