EVOLUTION, Issue 2 2010
James M. Sobel
Since Darwin published the "Origin," great progress has been made in our understanding of speciation mechanisms. The early investigations by Mayr and Dobzhansky linked Darwin's view of speciation by adaptive divergence to the evolution of reproductive isolation, and thus provided a framework for studying the origin of species. However, major controversies and questions remain, including: When is speciation nonecological? Under what conditions does geographic isolation constitute a reproductive isolating barrier? and How do we estimate the "importance" of different isolating barriers? Here, we address these questions, providing historical background and offering some new perspectives. A topic of great recent interest is the role of ecology in speciation. "Ecological speciation" is defined as the case in which divergent selection leads to reproductive isolation, with speciation under uniform selection, polyploid speciation, and speciation by genetic drift defined as "nonecological." We review these proposed cases of nonecological speciation and conclude that speciation by uniform selection and polyploidy normally involve ecological processes. Furthermore, because selection can impart reproductive isolation both directly through traits under selection and indirectly through pleiotropy and linkage, it is much more effective in producing isolation than genetic drift. We thus argue that natural selection is a ubiquitous part of speciation, and given the many ways in which stochastic and deterministic factors may interact during divergence, we question whether the ecological speciation concept is useful. We also suggest that geographic isolation caused by adaptation to different habitats plays a major, and largely neglected, role in speciation. We thus provide a framework for incorporating geographic isolation into the biological species concept (BSC) by separating ecological from historical processes that govern species distributions, allowing for an estimate of geographic isolation based upon genetic differences between taxa. Finally, we suggest that the individual and relative contributions of all potential barriers be estimated for species pairs that have recently achieved species status under the criteria of the BSC. Only in this way will it be possible to distinguish those barriers that have actually contributed to speciation from those that have accumulated after speciation is complete. We conclude that ecological adaptation is the major driver of reproductive isolation, and that the term "biology of speciation," as proposed by Mayr, remains an accurate and useful characterization of the diversity of speciation mechanisms. [source]

PERSPECTIVE: EVOLUTIONARY DEVELOPMENTAL BIOLOGY AND THE PROBLEM OF VARIATION

EVOLUTION, Issue 4 2000
David L. Stern
Abstract. One of the oldest problems in evolutionary biology remains largely unsolved. Which mutations generate evolutionarily relevant phenotypic variation? What kinds of molecular changes do they entail? What are the phenotypic magnitudes, frequencies of origin, and pleiotropic effects of such mutations? How is the genome constructed to allow the observed abundance of phenotypic diversity? Historically, the neo-Darwinian synthesizers stressed the predominance of micromutations in evolution, whereas others noted the similarities between some dramatic mutations and evolutionary transitions to argue for macromutationism. Arguments on both sides have been biased by misconceptions of the developmental effects of mutations. For example, the traditional view that mutations of important developmental genes always have large pleiotropic effects can now be seen to be a conclusion drawn from observations of a small class of mutations with dramatic effects. It is possible that some mutations, for example, those in cis -regulatory DNA, have few or no pleiotropic effects and may be the predominant source of morphological evolution. In contrast, mutations causing dramatic phenotypic effects, although superficially similar to hypothesized evolutionary transitions, are unlikely to fairly represent the true path of evolution. Recent developmental studies of gene function provide a new way of conceptualizing and studying variation that contrasts with the traditional genetic view that was incorporated into neo-Darwinian theory and population genetics. This new approach in developmental biology is as important for micro-evolutionary studies as the actual results from recent evolutionary developmental studies. In particular, this approach will assist in the task of identifying the specific mutations generating phenotypic variation and elucidating how they alter gene function. These data will provide the current missing link between molecular and phenotypic variation in natural populations. [source]

BIOLOGY OF CHRYSOPA PHYLLOCHROMA WESMAEL (NEUROPTERA: CHRYSOPIDAE).

INSECT SCIENCE, Issue 3 2004
II: INTRASPECIFIC INTERFERENCE AND SEARCHING CAPACITY
Abstract, The present study examined intraspecific interference and searching behavior of Chrysopa phyllochroma Wesmael (Neuroptera: Chrysopidae) for Aphis gossypii Glover (Homoptera: Aphididae) nymphs under laboratory and greenhouse conditions. The results were shown as follow: 1) In four different arenas (i.e. Petri dish, glass vessel, glass vessel with barriers in it, and cage with potted cotton plant), the predaceous efficiency of C. phyllochroma larvae varied with the predator density, the hunt constant (Q) and the intraspecific interference (m) increased with the prey density but decreased with the space heterogeneity; 2) In cage with potted cotton plant, the first- and second-instar green lacewing larvae consumed 13.6 and 29.4 cotton aphiddday respectively. The number of cotton aphids consumed by C. phyllochroma on lower leaves was significantly less than that on upper leaves; and 3) In cage with potted cotton plant, the percentage of the first- and second-instar green lacewing larvae located on upper leaves was significant less than that on lower leaves. [source]

CARTILAGE IN BONE BIOLOGY AND PATHOPHYSIOLOGY

INTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 2006
Article first published online: 6 JUL 200
No abstract is available for this article. [source]

BIOLOGY AND ECOLOGY OF FISHES.

JOURNAL OF FISH BIOLOGY, Issue 3 2004
By J. S. Diana. xv 498 pp.
No abstract is available for this article. [source]

CELL WALL BIOLOGY IN RED ALGAE: DIVIDE AND CONQUER

JOURNAL OF PHYCOLOGY, Issue 5 2000
Valerie Vreeland
First page of article [source]

FREUD'S LETTERS TO FLIESS: FROM SEDUCTION TO SEXUAL BIOLOGY, FROM PSYCHOPATHOLOGY TO A CLINICAL ANTHROPOLOGY

THE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 5 2001
Tomas Geyskens
The author describes the development of Freud's theory of neurosis from 1892 onwards, starting with his distinction between the actual neuroses and the psychoneuroses and his discovery of a specific, sexual aetiology for both, until which point it remained limited to pathology. The problem of the aetiology of perversion, however, confronted him with a paradox within the theory of seduction: how can an infantile sexual pleasure produce unpleasure when it is remembered at the time of puberty? This problem could not be solved within the framework of the seduction theory because the asexuality of childhood was essential to this theory. For an answer Freud had to turn to biology. He considered that the transformation of an infantile pleasure into unpleasure presupposed an organic repression of non-genital sexual pleasure. This hypothesis of organic repression radically changed the anthropological claim of Freud's theory. As long as he was looking for a specific aetiology of neurosis and perversion, Freud's theory remained restricted to pathology. However, when he introduced infantile sexuality and its organic repression as universal organic processes, the strict distinction between normality and pathology could not be maintained. The author concludes that by turning to sexual biology, Freud transformed psychopathology into a clinical anthropology. [source]

Purine Metabolism in Heart Failure: Oxidant Biology and Therapeutic Indications

CONGESTIVE HEART FAILURE, Issue 5 2008
John Anthony Bauer PhD
No abstract is available for this article. [source]

Conservation Biology in Asia: the Major Policy Challenges

CONSERVATION BIOLOGY, Issue 4 2009
JEFFREY A. McNEELY
Asia; bosques; comercio de vida silvestres; conflicto humano-animal; economía Abstract:,With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human,animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders. Resumen:,Con aproximadamente la mitad de la población humana y economías prósperas, Asia enfrenta numerosos retos para su biodiversidad. La sección Asia de la Sociedad para la Biología de la Conservación ha identificado algunos temas políticos claves en los que se puede hacer un progreso significativo. Estos incluyen el desarrollo de nuevas fuentes de financiamiento para la conservación de bosques; la identificación de impactos potenciales de las energías alternativas sobre la conservación de la biodiversidad; reducción del comercio de especies de animales y plantas en peligro; un enfoque especial en la conservación de la biodiversidad montana; promoción de investigación relevante; garantía de que la biología de la conservación contribuye a convenios internacionales y mecanismos de financiamiento; utilización de la biología de la conservación para lograr un mejor entendimiento de enfermedades zoonóticas; mejor atención a los conflictos humanos-animales; reforzamiento de la conservación basada en comunidades y utilización de la biología de la conservación para atender los problemas de déficit de agua en gran parte de Asia. Estos retos se pueden atender mediante una mejor cooperación regional entre los principales actores. [source]

Conservation Challenges for the Austral and Neotropical America Section

CONSERVATION BIOLOGY, Issue 4 2009
GERARDO CEBALLOS
América Austral y Neotropical; América Latina; desarrollo de capacidades Abstract:,The Austral and Neotropical America (ANA) section of the Society for Conservation Biology includes a vast territory with some of the largest relatively pristine ecosystems in the world. With more than 573 million people, the economic growth of the region still depends strongly on natural resource exploitation and still has high rates of environmental degradation and biodiversity loss. A survey among the ANA section membership, with more than 700 members, including most of the section's prominent ecologists and conservationists, indicates that lack of capacity building for conservation, corruption, and threats such as deforestation and illegal trade of species, are among the most urgent problems that need to be addressed to improve conservation in the region. There are, however, strong universities and ecology groups taking the lead in environmental research and conservation, a most important issue to enhance the ability of the region to solve conservation and development conflicts. Resumen:,La sección América Austral y Neotropical (AAN) de la Sociedad para la Biología de la Conservación incluye un vasto territorio con unos de los ecosistemas relativamente prístinos más extensos del mundo. Con más de 573 millones de habitantes, el crecimiento económico de la región aun depende fuertemente de la explotación de recursos naturales y aún tiene altas tasas de degradación ambiental y pérdida de biodiversidad. Un sondeo de la membresía de la sección AAN, con más de 700 miembros, incluyendo la mayoría de los ecólogos y conservacionistas más prominentes de la sección, indica que la carencia de desarrollo de capacidades para la conservación, la corrupción y amenazas como la deforestación y el comercio ilegal de especies, son algunos de los problemas que requieren ser atendidos más urgentemente para mejorar la conservación en la región. Sin embargo, hay universidades y grupos ecológicos que están tomando el liderazgo en investigación ambiental y conservación, un tema importante para mejorar la habilidad de la región para resolver conflictos de conservación y desarrollo. [source]

Leadership: a New Frontier in Conservation Science

CONSERVATION BIOLOGY, Issue 4 2009
JIM C. MANOLIS
estrategia; influencia; liderazgo; manejo; política Abstract:,Leadership is a critical tool for expanding the influence of conservation science, but recent advances in leadership concepts and practice remain underutilized by conservation scientists. Furthermore, an explicit conceptual foundation and definition of leadership in conservation science are not available in the literature. Here we drew on our diverse leadership experiences, our reading of leadership literature, and discussions with selected conservation science leaders to define conservation-science leadership, summarize an exploratory set of leadership principles that are applicable to conservation science, and recommend actions to expand leadership capacity among conservation scientists and practitioners. We define 2 types of conservation-science leadership: shaping conservation science through path-breaking research, and advancing the integration of conservation science into policy, management, and society at large. We focused on the second, integrative type of leadership because we believe it presents the greatest opportunity for improving conservation effectiveness. We identified 8 leadership principles derived mainly from the "adaptive leadership" literature: recognize the social dimension of the problem; cycle frequently through action and reflection; get and maintain attention; combine strengths of multiple leaders; extend your reach through networks of relationships; strategically time your effort; nurture productive conflict; and cultivate diversity. Conservation scientists and practitioners should strive to develop themselves as leaders, and the Society for Conservation Biology, conservation organizations, and academia should support this effort through professional development, mentoring, teaching, and research. Resumen:,El liderazgo es una herramienta crítica para la expansión de la influencia de la ciencia de la conservación, pero los avances recientes en los conceptos y práctica del liderazgo son subutilizados por los científicos de la conservación. Más aun, en la literatura no hay una fundamentación conceptual ni definición de liderazgo en la ciencia de la conservación. Aquí nos basamos en nuestras experiencias de liderazgo, nuestra lectura de literatura sobre liderazgo y discusiones con líderes selectos de la ciencia de conservación para definir liderazgo para la ciencia de la conservación, resumir un conjunto exploratorio de principios de liderazgo aplicables a la ciencia de la conservación y recomendar acciones para expandir la capacidad de liderazgo entre los científicos y los practicantes de la conservación. Definimos dos tipos de liderazgo de la ciencia de la conservación: configuración de la ciencia de la conservación mediante investigación original, y avance hacia la integración del liderazgo en la ciencia de la conservación en la política, el manejo y la sociedad en general. Nos centramos en el segundo tipo de liderazgo porque consideramos que presenta la mejor oportunidad para mejorar la efectividad de la conservación. Identificamos ocho principios de liderazgo derivados principalmente de la literatura sobre "liderazgo adaptativo": reconocer la dimensión social del problema; alternar entre acción y reflexión frecuentemente; obtener y mantener atención; combinar fortalezas de múltiples líderes; extender el alcance mediante redes de relaciones; organizar el esfuerzo estratégicamente; evitar conflictos productivos y desarrollar la biodiversidad. Los científicos y los practicantes de la conservación deberían esforzarse para desarrollarse como líderes y la Sociedad para la Biología de la Conservación, las organizaciones de conservación y la academia deberían respaldar este esfuerzo mediante el desarrollo profesional, la tutoría, la enseñanza y la investigación. [source]

The Role of Religion in the HIV/AIDS Intervention in Africa: a Possible Model for Conservation Biology

CONSERVATION BIOLOGY, Issue 4 2008
Stephen Mufutau Awoyemi
No abstract is available for this article. [source]

Value and Advocacy in Conservation Biology: Crisis Discipline or Discipline in Crisis?

CONSERVATION BIOLOGY, Issue 1 2008
Kai M. A. Chan
No abstract is available for this article. [source]

Availability of Formal Academic Programs in Conservation Biology in Latin America

CONSERVATION BIOLOGY, Issue 6 2007
Martín Mendez
First page of article [source]

Editorial: The Success,and Challenges,of Conservation Biology

CONSERVATION BIOLOGY, Issue 4 2006
Gary K. Meffe Editor
No abstract is available for this article. [source]

Conservation Biology at Twenty

CONSERVATION BIOLOGY, Issue 3 2006
Gary K. Meffe Editor
No abstract is available for this article. [source]

Conservation Biology: Views from the Ecological Sciences

CONSERVATION BIOLOGY, Issue 3 2006
JOSÉ SARUKHÁN
No abstract is available for this article. [source]

Landscape Planning and Conservation Biology: Systems Thinking Revisited

CONSERVATION BIOLOGY, Issue 3 2006
JOAN IVERSON NASSAUER
No abstract is available for this article. [source]

Glimpses of Conservation Biology, Act II

CONSERVATION BIOLOGY, Issue 3 2006
THOMAS E. LOVEJOY
No abstract is available for this article. [source]

Conservation Biology in the Pacific

CONSERVATION BIOLOGY, Issue 6 2004
Harry F. Recher Editor, Pacific Conservation Biology
No abstract is available for this article. [source]

Everything You Wanted to Know About Conservation Biology

CONSERVATION BIOLOGY, Issue 1 2004
Andrew T. Smith
No abstract is available for this article. [source]

The Speke's Gazelle Breeding Program as an Illustration of the Importance of Multilocus Genetic Diversity in Conservation Biology: Response to Kalinowski et al.

CONSERVATION BIOLOGY, Issue 4 2002
Alan R. Templeton
First page of article [source]

Conservation Biology for the Biodiversity Crisis

CONSERVATION BIOLOGY, Issue 1 2002
David M. Olson
No abstract is available for this article. [source]

The Context of Conservation Biology

CONSERVATION BIOLOGY, Issue 4 2001
Gary K. Meffe
No abstract is available for this article. [source]

Conservation Biology and Private Land: Shifting the Focus

CONSERVATION BIOLOGY, Issue 5 2000
David A. Norton
No abstract is available for this article. [source]

Making the Monkey: How the Togean Macaque Went from "New Form" to "Endemic Species" in Indonesians' Conservation Biology

CULTURAL ANTHROPOLOGY, Issue 4 2004
Celia Lowe
Indonesian scientists inhabit a postcolonial world where they are both elite (within the nation) and subaltern (within transnational science) at precisely the same moments. A study of science that is neither "ethno" nor "Euro" requires a postcolonial refiguration not only of how science's matter is made but of where and by whom. In the 1990s, the Togean macaque (Macaca togeanus) was proposed as a new species endemic to the Togean Islands, the proposed site of a new conservation area in Central Sulawesi, Indonesia. In the scientific production of biodiverse nature, Indonesian primatologists identified the monkey first as a "new form," then as a "dubious name," and subsequently, as an "endemic species." Throughout these acts of making, unmaking, and remaking the monkey, its unique and endemic status was important for developing Indonesian conservation biology, attracting foreign donors, and enlisting government and public interest in Togean Island nature, even as forms of nature important to Togean peoples were overwritten in this process. [source]

Peer Commmentaries on Neural plasticity and human development: the role of early experience in sculpting memory systems By Charles A. Nelson

DEVELOPMENTAL SCIENCE, Issue 2 2000
Article first published online: 28 JUN 200
Olivier Pascalis and Michelle de Haan, Subcortical lesion-cortical lesion: what about the hippocampus?, p. 131 J. Steven Reznick, Biology versus experience: balancing the equation, p. 133 [source]

Biology of the solitary wasp Trypoxylon (Trypargilum) agamemnon Richards 1934 (Hymenoptera: Crabronidae) in trap-nests

ACTA ZOOLOGICA, Issue 4 2010
Maria Luisa Tunes Buschini
Abstract Buschini, M.L.T. and Fajardo, S. 2009. Biology of the solitary wasp Trypoxylon (Trypargilum) agamemnon Richards 1934 (Hymenoptera: Crabronidae) in trap-nests. ,Acta Zoologica (Stockholm) 91: 426,432. Some Trypoxylon species build their nests in preexisting tubular cavities like hollow stems and beetle borings in branches. Study of the biology of these insects is relatively easy because the females of these wasps nest with enormous success in trap-nests. The aim of this study was to investigate the abundance, seasonality and life-history of Trypoxylon agamemnon. For capture of these insects, trap-nests were installed in the Parque Municipal das Araucárias in araucaria forest, grassland and swamp, from December, 2001 to December, 2005. Two hundred and ninety seven nests were obtained. They were constructed more often during the summer (from December to April). The nests were built only in araucaria forest and consisted of a linear series of cells, divided by mud partitions, whose number varied from 1 to 7. Normally they have only one vestibular cell. The inner cells had been provisioned, usually with spiders of Anyphaenidae family. Sex-ratio was strongly female biased. Its main natural enemies included Chrysididae, Ichneumonidae and Tachinidae. [source]

The costs and benefits of fast living

ECOLOGY LETTERS, Issue 12 2009
Karen E. Rose
Abstract Growth rates play a fundamental role in many areas of biology (Q. Rev. Biol., 67, 1992, 283; Life History Invariants. Some Explorations of Symmetry in Evolutionary Biology, 1993; Philos. Trans. R. Soc. Lond. B Biol. Sci., 351, 1996, 1341; Plant Strategies, Vegetation Processes, and Ecosystem Properties, 2002; Trends Ecol. Evol., 18, 2003, 471; Q. Rev. Biol., 78, 2003, 23; J. Ecol., 95, 2007, 926.) but the cost and benefits of different growth rates are notoriously difficult to quantify (Q. Rev. Biol., 72, 1997, 149; Funct. Ecol., 17, 2003, 328). This is because (1) growth rate typically declines with size and yet the most widely used growth measure , relative growth rate or RGR (conventionally measured as the log of the ratio of successive sizes divided by the time interval) , is not size-corrected and so confounds growth and size, (2) organisms have access to different amounts of resource and (3) it is essential to allow for the long-term benefits of larger size. Here we experimentally demonstrate delayed costs and benefits of rapid growth in seven plant species using a novel method to calculate size-corrected RGR. In control treatments, fast-growing plants benefited from increased reproduction the following year; however, fast-growing plants subjected to an experimental stress treatment (defoliation) showed strongly reduced survival and reproduction the following year. Importantly, when growth was estimated using the classical RGR measure, no costs or benefits were found. These results support the idea that life-history trade-offs have a dominant role in life-history and ecological theory and that the widespread failure to detect them is partly due to methodological shortcomings. Ecology Letters (2009) 12: 1379,1384 [source]