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1.
We hypothesize that juvenile baboons are less efficient foragers than adult baboons owing to their small size, lower level of knowledge and skill, and/or lesser ability to maintain access to resources. We predict that as resources are more difficult to extract, juvenile baboons will demonstrate lower efficiency than adults will because of their lower levels of experience. In addition, we hypothesize that juvenile baboons will be more likely to allocate foraging time to easier-to-extract resources owing to their greater efficiency in acquiring those resources. We use feeding efficiency and time allocation data collected on a wild, free-ranging, non-provisioned population of chacma baboons (Papio hamadryas ursinus) in the Moremi Wildlife Reserve, Okavango Delta, Botswana to test these hypotheses. The major findings of this study are: 1. Juvenile baboons are significantly less efficient foragers than adult baboons primarily for difficult-to-extract resources. We propose that this age-dependent variation in efficiency is due to differences in memory and other cognitive functions related to locating food resources, as is indicated by the greater amount of time juvenile baboons spend searching for food. There is no evidence that smaller body size or competitive disruption influences the differences in return rates found between adult and juvenile baboons in this study. 2. An individual baboon’s feeding efficiency for a given resource can be used to predict the duration of its foraging bouts for that resource. These results contribute both to our understanding of the ontogeny of behavioral development in nonhuman primates, especially regarding foraging ability, and to current debate within the field of human behavioral ecology regarding the evolution of the juvenile period in primates and humans. Sara E. Johnson is Assistant Professor of Anthropology at California State University, Fullerton. She received her Ph.D. in Anthropology (Human Evolutionary Ecology) from the University of New Mexico in 2001. She uses behavioral ecology and life history theory to address her research interests in the evolution of primate and human growth; ecological variation and phenotypic plasticity in growth and development; ecological variation in life course trajectories, including fertility, health, morbidity, and mortality differentials; food acquisition and production related to nutrition; societal transofmration and roles of the elderly among indigenous peoples; and women’s reproductive and productive roles in both traditional and nontraditional societies. For the past decade she has conducted research on these issues in several different populations, including chacma baboons in the Okavango Delta of Botswana, two multiethnic communities of forager/agropastoralists in the Okavango Delta of Botswana, and among New Mexican men. John Bock is Associate Professor of Anthropology at California State University at Fullerton and is Associate Editor of Human Nature. He received a Ph.D. in Anthropology (Human Evolutionary EcologY) from the University of New Mexico in 1995, and from 1995 to 1998 was an Andrew W. Mellon Foundation postdoctoral fellow in demography and epidemiology at the National Centre for Epidemiology and Population Health at Australian National University. His recent research has focused on applying life history theory to understanding the evolution of the primate and human juvenile period. Bock has been conducting research among the Okavango Delta peoples of Botswana since 1992, and his current research there is an examination of child development and family demography in relation to socioecology and the HIV/AIDS epidemic. Other research is focused on health disparties among minorities and indigenous peoples in Botswana and the United States related to differential access to health care.  相似文献   

2.
Gifts of Pride and Love: The Cultural Significance of Kiowa and Comanche Lattice Cradles. Haffenreffer Museum of Anthropology, Brown University, Bristol, RI, 1998; Gilcrease Museum, Tulsa, OK, December 4, 1999-February 2000; Heard Museum, Phoenix, AZ, April 20-July 16, 2001; Fowler Museum of Cultural History, UCLA, Los Angeles, CA, August 27, 2000-January 16, 2001; National Museum of the American Indian, Smithsonian Institution, Gustav Heye Center, New York, NY, March-May 2001; Oklahoma Museum of Natural History, Norman, OK, June-September 2001; Mashantucket Pequot Museum and Research Center, Ledyard, CT, October 2001-January 2002.
Gifts of Pride and Love: Kiowa and Comanche Cradles. Barbara A. Hail. ed. Bristol, RI: Haffenreffer Museum of Anthropology, Brown University, 2000. 135 pp.  相似文献   

3.
Recent evidence suggests that the ratio of the lengths of the second and fourth fingers (2D:4D) may reflect degree of prenatal androgen exposure in humans. In the present study, we tested the hypotheses that 2D:4D would be associated with ratings of men’s attractiveness and with levels of behavioral displays during social interactions with potential mates. Our results confirm that male 2D:4D was significantly negatively correlated with women’s ratings of men’s physical attractiveness and levels of courtship-like behavior during a brief conversation. These findings provide novel evidence for the organizational effects of hormones on human male attractiveness and social behavior. This work was supported by a Hind’s Fund Research Grant from the Committee on Evolutionary Biology at the University of Chicago to J.R.R. and by NIH grants R01-MH62577 and K02-MH63097 to D.M. James Roney, Ph.D., is now an assistant professor of psychology at the University of California, Santa Barbara. His research interests are in human evolutionary psychology and behavioral endocrinology. Dario Maestripieri, Ph.D., is an associate professor of Human Development at the University of Chicago. He has broad research interests in behavior, development, and evolution.  相似文献   

4.
Here we attempt to define a specifically human ecology within which male reproductive strategies are formulated. By treating the domestic and public spheres of social life as "ecological niches" that men have been forced to compete within or to avoid as best they can, we generate a typology of four "social modes" of human male behavior. We then attempt to explain the broad distribution of social modes within and between human groups based on the relative intensity of scramble and contest competition. This research was completed with the help of a Lowell M. Durham, Jr. Fellowship at the Tanner Humanities Center, University of Utah. Lars Rodseth (Ph.D., University of Michigan 1993) is Assistant Professor of Anthropology at the University of Utah. He has conducted fieldwork in Nepal and Micronesia and is the author of "Distributive Models of Culture: A Sapirian Alternative to Essentialism," American Anthropologist (1998) 100:55–69. Shannon A. Novak (Ph.D., University of Utah 1999) is Assistant Professor of Anthropology at Indiana State University. She has conducted fieldwork in Croatia and the United Kingdom and is the author of "Perimortem Processing of Human Remains among the Great Basin Fremont," International Journal of Osteoachaeology (2000) 10:65–75.  相似文献   

5.
Human Sacrifice, Militarism, and Rulership: Materialization of State Ideology at the Feathered Serpent Pyramid, Teotihuacan. Saburo Sugiyama. New York: Cambridge University Press, 2005. 280 pp.  相似文献   

6.
Book Reviews     
《American anthropologist》1953,55(5):734-736
Book reviewed in this article:
Introduction to Social Psychology. E. Llewellyn Queener.
The Development of Human Behavior. Richard Dewey and W. J. Humber.
Social Psychology. Solomon E. Asch.
Social Psychology: An Analysis of Human Behavior. Leonard W. Doob.
Social Psychology. Robert E. L. Faris.
Fundamentals of Social Psychology. Eugene L. and Ruth E. Hartley.
Readings in Social Psychology. Prepared for the Committee on the Teaching of Social Psychology of The Society for the Psychological Study of Social Issues. Revised Edition. Editorial Committee: Guy E. Swanson, Theodore M. Newcomb, Eugene L. Hartley, and others.  相似文献   

7.
Book Reviews     
Book reviewed in this article: Australian Dreaming. 40.000 years of Aboriginal History . Edited by Jennifer Isaacs Radio Power. A History of 3ZZ Access Radio . By Joan Dugdale Department of Anthropology, University of Western Australia Introduction to Australian Society: A Sociological Perspective . By Donald Edgar The New South Wales Wheat Frontier. 1851 to 1911 . By M. E. Robinson Department of Anthropology, University of Sydney. Heroin in Australia . By David Hirst Department of Anthropology and Sociology, University of Queensland. The Quest for Gaia. A Book of Changes . By Kit Pedler Drinking Careers. Occupations, Drinking Habits, and Drinking Problems . By Martin A. Plant Northern Territory Department of Health, Darwin. Families in Former Times: Kinship, Household and Sexuality . By Jean-Louis Flandrin. Translated by Richard Southern Changing Images of the Family . Edited by Virginia Tufte and Barbara Myerhoff Department of Anthropology, Western Australian Museum. Give and Take. Exchange in Wola Society . By Paul Sillitoe Department of Prehistory and Anthropoloy, S.G.S. Caste: The Emergence of the South Asian Social System . By Morton Klass David Mearns Department of Anthropology, University of Adelaide. Anthropological Structures of Madness in Black Africa . By I. Sow. Translated by Joyce Diamenti Basic Problems of Ethnopsychiatry . By George Devereux Department of Anthropology, University of Otago. Who Should Know What? Social Science, Privacy and Ethics . By J. A. Barnes Department of Sociology, University of N.S.W. Arnold Van Gennep. The Creator of French Ethnography . By Nicole Belmont Department of Prehistory anrf Anthropology, Australian National University. Man, Mind, and Science. A History of Anthropology . By Murray J. Leaf Department of Sociology, University of N.S.W. The Conceptualisation and Explanation of Processes of Social Change . Edited by David Riches School of Behavioural Sciences, Macquarie University. Day of Shining Red. An Essay on Understanding Ritual . By Gilbert Lewis Department of Prehistory and Anthropology, Australian National University. Living Archaeology . By R. A. Gould. New Department of Prehistory and Archaeology, University of New England Experimental Determinatiou of Stone Tool Uses: A Microwear Analysis . By Lawrence H. Keeley Division of Prehistory, La Trobe University. Archaeological Constructs. An Aspect of Theoretical Archaeology . By Jean-Claude Gardin Division of Prehistory, La Trobe University. The Performing Arts. Music and Dance . Edited by John Blacking and Joann W. Kealiinohomoku Department of Sociology, University of New England.  相似文献   

8.
Life history theory’s principle of allocation suggests that because immature organisms cannot expend reproductive effort, the major trade-off facing juveniles will be the one between survival, on one hand, and growth and development, on the other. As a consequence, infants and children might be expected to possess psychobiological mechanisms for optimizing this trade-off. The main argument of this paper is that the attachment process serves this function and that individual differences in attachment organization (secure, insecure, and possibly others) may represent facultative adaptations to conditions of risk and uncertainty that were probably recurrent in the environment of human evolutionary adaptedness. An early version of this paper was presented in the symposium “Childhood in Life-history Perspective: Developing Views” organized by Gilda Morelli and Paula Ivey for the Annual Meeting of the Society for Cross-Cultural Research in Santa Fe, New Mexico, February 16–20, 1994. James S. Chisholm recently joined the Department of Anatomy and Human Biology at the University of Western Australia. Previously he taught in the Department of Anthropology at the University of New Mexico and in the Division of Human Development at the University of California, Davis. He is a biosocial anthropologist whose research interests lie in the fields of human behavioral biology, evolutionary ecology, and life history theory, where he focuses on infant social-emotional development and the development of reproductive strategies in adolescence and young adulthood. In addition to numerous articles he is the author ofNavajo Infancy: An Ethological Study of Child Development (Aldine de Gruyter, 1983).  相似文献   

9.
Invasive algal species have the potential to change the structure and ecology of native algal communities. One well‐known invader, the large Japanese kelp Undaria pinnatifida, has recently become established at several locations along the central and southern California coast (Monterey, Santa Barbara, Catalina, and others). Previous to its introduction in the northeastern Pacific, Undaria has become established along the coastlines of several countries, including Australia, New Zealand, Argentina, England, and France. However, the seasonal population dynamics, rate of spread, and impact on local communities at each invasion site varies. Undaria in the Santa Barbara, CA harbor exhibits two distinct recruitment pulses per year (fall, late winter), with nonoverlapping generations of adult individuals. Individuals can grow rapidly and become reproductive a month after appearing as recruits (2–3 cm long), indicating a potential for rapid spread. However, Undaria may be effectively controlled by grazing via natural recruitment of the kelp crab Pugettia producta. However, Undaria invasions in other California invasions have not been controlled by herbivory, and Undaria populations in these areas have the potential to compete with a wide diversity of native California kelp species for habitat space and light.  相似文献   

10.
This study investigated sex differences in interest in infants among children, adolescents, young adults, and older individuals. Interest in infants was assessed with responses to images depicting animal and human infants versus adults, and with verbal responses to questionnaires. Clear sex differences, irrespective of age, emerged in all visual and verbal tests, with females being more interested in infants than males. Male interest in infants remained fairly stable across the four age groups, whereas female interest in infants was highest in childhood and adolescence and declined thereafter, particularly for the responses to visual stimuli. The observed developmental changes in female interest in infants are consistent with the hypothesis that they represent a biological adaptation for parenting. This study was supported by NIH grants R01-MH57249, R01-MH62577, and K02-MH63097. Dario Maestripieri, Ph.D., is an assistant professor of Human Development and Evolutionary Biology at the University of Chicago. He has broad research interests in behavior, development, and evolution, and conducted research on primate parenting and development at the University of Cambridge and at the Yerkes Regional Primate Research Center before moving to Chicago. Suzanne Pelka is a graduate student in Human Development at the University of Chicago.  相似文献   

11.
Children’s play is widely believed by educators and social scientists to have a training function that contributes to psychosocial development as well as the acquisition of skills related to adult competency in task performance. In this paper we examine these assumptions from the perspective of life-history theory using behavioral observation and household economic data collected among children in a community in the Okavango Delta of Botswana where people engage in mixed subsistence regimes of dry farming, foraging, and herding. We hypothesize that if play contributes to adult competency then time allocation to play will decrease as children approach adult levels of competence. This hypothesis generates the following predictions: (1) time allocated to play activities that develop specific productive skills should decline in relation to the proportion of adult competency achieved; (2) children will spend more time in forms of play that are related to skill development in tasks specific to the subsistence ecology in which that child participates or expects to participate; and (3) children will spend more time in forms of play that are related to skill development in tasks clearly related to the gender-specific productive role in the subsistence ecology in which that child participates or expects to participate. We contrast these expectations with the alternative hypothesis that if play is not preparatory for adult competence then time allocated to each play activity should diminish at the same rate. This latter hypothesis generates the following two predictions: (1) time allocation to play should be unaffected by subsistence regime and (2) patterns of time allocation to play should track patterns of growth and energy balance. Results from multiple regression analysis support earlier research in this community showing that trade-offs between immediate productivity and future returns were a primary determinant of children’s activity patterns. Children whose labor was in greater demand spent significantly less time playing. In addition, controlling for age and gender, children spent significantly more time in play activities related to tasks specific to their household subsistence economy. These results are consistent with the assertion that play is an important factor in the development of adult competency and highlight the important contributions of an evolutionary ecological perspective in understanding children’s developmental trajectories. John Bock is an associate professor of anthropology at Cal State Fullerton and Associate Editor of Human Nature. He received a Ph.D. in Anthropology (Human Evolutionary Ecology) from the University of New Mexico in 1995, and from 1995 to 1998 was an Andrew W. Mellon Foundation postdoctoral fellow in demography and epidemiology at the National Centre for Epidemiology and Population Health at Australian National University. His recent research has focused on the application of life-history theory to understanding the evolution of the primate and human juvenile period. Bock has been conducting research among the Okavango Delta peoples of Botswana since 1992, and his current research there is an examination of child development and family demography in relation to socioecology and the HIV/AIDS epidemic. Other research is focused on health disparities among minorities and indigenous peoples in Botswana and the United States related to differential access to health care. Sara E. Johnson is an assistant professor of anthropology at California State University, Fullerton. She received her Ph.D. in Anthropology (Human Evolutionary Ecology) from the University of New Mexico in 2001. She uses behavioral ecology and life-history theory to address her research interests in the evolution of primate and human growth; ecological variation and phenotypic plasticity in growth and development; ecological variation in life course trajectories, including fertility, health, morbidity, and mortality differentials; food acquisition and production related to nutrition; societal transformation and roles of the elderly among indigenous peoples; and women’s reproductive and productive roles in both traditional and nontraditional societies. Over the past 10 years she has conducted research on these issues in several different populations, including chacma baboons in the Okavango Delta of Botswana, two multiethnic communities of forager/agropastoralists in the Okavango Delta of Botswana, and among New Mexican men.  相似文献   

12.
Investment in children is examined using a nationally representative sample of 11,211 black (African) households in South Africa. I randomly selected one child from each household in the sample and calculated the average genetic relatedness of the other household members to the focal child. Using multivariate statistical analysis to control for background variables such as age and sex of child, household size, and socioeconomic status, I examine whether the coefficient of relatedness predicts greater household expenditures on food, on health care, and on children’s clothing. I also test whether relatedness is associated with health and schooling outcomes. The results are consistent with an inclusive fitness model: Households invest more in children who are more closely related. Two exceptions were found: in rural areas, genetic relatedness was negatively associated with money spent on food and on health care. Explanations for these results are discussed. Preliminary versions of this paper were presented at the 2003 Human Behavior and Evolution Society annual meeting in Lincoln, Nebraska, and at the 2003 Human Behavioral Ecology Workshop in Bangor, Maine. Kermyt G. Anderson is Assistant Professor at the Department of Anthropology at the University of Oklahoma. He received his Ph.D. from the University of New Mexico in 1999 and was a postdoctoral research fellow at the Population Studies Center at the University of Michigan for three years. His research focuses on biosocial models of fertility, parental investment, paternity confidence, marriage/divorce, and children’s outcomes. He is currently involved in a long-term longitudinal survey of young adults in Cape Town, South Africa, and in several projects examining the effects of HIV/AIDS in the U.S.  相似文献   

13.
The National Longitudinal Study of Adolescent Health data were used to test predictions from life history theory. We hypothesized that (1) in young adulthood an emerging life history strategy would exist as a common factor underlying many life history traits (e.g., health, relationship stability, economic success), (2) both environmental harshness and unpredictability would account for unique variance in expression of adolescent and young adult life history strategies, and (3) adolescent life history traits would predict young adult life history strategy. These predictions were supported. The current findings suggest that the environmental parameters of harshness and unpredictability have concurrent effects on life history development in adolescence, as well as longitudinal effects into young adulthood. In addition, life history traits appear to be stable across developmental time from adolescence into young adulthood.
Barbara Hagenah BrumbachEmail:

Barbara Hagenah Brumbach   is an assistant professor in the Department of Psychology at Northern Arizona University. Her research examines individual differences in life history strategy and ecological predictors of the development of life history strategy over the life course. Aurelio José Figueredo   is a professor of psychology at the University of Arizona and serves as director of the Graduate Program in Ethology and Evolutionary Psychology. His major area of research interest is the evolutionary psychology and behavioral development of life history strategy, sex, and violence in human and nonhuman animals, and the quantitative ethology and social development of insects, birds, and primates. Bruce J. Ellis   is a professor in the Division of Family Studies and Human Development and the John & Doris Norton Endowed Chair in Fathers, Parenting, and Families at the University of Arizona. He seeks to integrate evolutionary and developmental perspectives in his research on family environments, child stress reactivity, and sexual development.  相似文献   

14.
This study examines the family environments and hormone profiles of 316 individuals aged 2 months-58 years residing in a rural village on the east coast of Dominica, a former British colony in the West Indies. Fieldwork was conducted over an eight-year period (1988–1995). Research methods and techniques include radioimmunoassay of cortisol and testosterone from saliva samples (N=22,340), residence histories, behavioral observations of family interactions, extensive ethnographic interview and participant observation, psychological questionnaires, and medical examinations. Analyses of data indicate complex, sex-specific effects of family environment on endocrine function. Male endocrine profiles exhibit greater sensitivity to presence of father than do female endocrine profiles. Father-absent males tend to have (a) low cortisol levels during infancy, (b) high or abnormal cortisol profiles during childhood and adolescence, and (c) high cortisol and low testosterone levels during adulthood compared with those of males raised with a resident father. These results indicate that early family environment has significant effects on endocrine response throughout male life histories. Mark V. Flinn is an Associate Professor of Anthropology at the University of Missouri, Columbia. He studies family relationships, endocrine stress response, and child health from a mix of evolutionary and developmental psychology perspectives. Robert J. Quinlan is a graduate student in the Department of Anthropology at the University of Missouri, Columbia. His interests include time allocation, family relationships, and medical anthropology. He is planning a long-term ethnographic study of cross-cousin marriage among the E’nyepa of Venezuela. Mark T. Turner is a graduate student in the Department of Anthropology at Northwestern University. He studies covariance of mother and infant hormone and immune function in naturalistic settings using assays from saliva and breast milk samples and ethnographic observations. Seamus A. Decker is a graduate student in the Department of Anthropology at Emory University. He has studied social factors associated with daily variations of salivary cortisol and testosterone levels among males in a Caribbean village. He is currently investigating levels of stress in rural and urban populations in Botswana. Barry G. England is an Associate Professor of Pathology and director of the ligand assay laboratories of the University of Michigan Hospitals. His primary interests concern reproductive endocrinology.  相似文献   

15.
Summary Diffuse and synaptic nerve nets are present in the coenenchymal mesoglea and ectoderm of Muricea and Lophogorgia colonies. The nerve nets extend into the polyp column and tentacles maintaining a subectodermalmesogleal position. The density of nerve elements is low in comparison with similar nerve nets found in pennatulids.In the column of the polyp anthocodium, and throughout the oral disk region, neurons cross the mesoglea and enter the polyp endoderm. These neurons presumably connect with the endodermal nerve net which innervates the septal musculature. The trans-mesogleal neurons probably represent the connection between colonial and polyp nervous systems.In the tentacles, longitudinal ectodermal musculature is present with an overlying nerve plexus. These muscles and nerves, as well as tentacular sensory cells, are well represented in the oral side of the tentacles only.Presumed sensory cells form ciliary cone complexes in which one cell possesses an apical cilium. The other cells as well as the centrally located nematocyte contribute microvilli to the cone. The basal portion of the sensory cells is drawn into one or more neurite-like processes which enter the ectodermal nerve plexus. Similar processes form synapses with longitudinal muscle cells and nematocytes. The sensory cells of the ciliary cones presumably include chemoreceptors which can activate or modify nematocyst discharge, local muscle twitches, and tentacle bending.This work was supported by Office of Naval Research Contract N00014-75-C-0242, NSF Grant BMS 74-23242 and General Research Funds of the University of California, Santa Barbara. We wish to thank Dr. Steven K. Fisher for the use of facilities in his lab. This paper is part of a thesis to be submitted by R.A.S. to the Department of Biological Sciences, University of California, Santa Barbara in partial fulfillment of the requirements for the Ph. D.  相似文献   

16.
The common west coast lichen Ramalina menziesii Tayl. has been studied in an attempt to determine the extent of morphological variation and to understand the factors that determine its form. An analysis of a typical population near Santa Barbara, CA, suggested that intrapopulation variation in form was controlled primarily by size increase during growth. Test populations obtained from latitudes as far north as 54°N and as far south as 28°N had values for various morphological characters that were very similar to the Santa Barbara population. It is concluded that variation in form may be the result of differential rates of growth and possibly varying frequency of environmental stresses which disintegrate the thallus.  相似文献   

17.
In this paper we outline the activities of young girls in a Toba community of northern Argentina and examine the effect of girl helpers on time allocation of nursing women. Activity budgets were obtained for 41 girls aged 3 to 15 using spot observations. Girls spent substantial portions of observations engaged in helping behaviors. Individual values varied with age, anthropometric characteristics, and birth order. Activity budgets of 21 nursing women were obtained through focal observation sessions. Women living in households with girls aged 7 to 15 allocated 17% less time to domestic work and 9% more time to socializing during afternoon observation sessions. For nursing women in this community, direct childcare (provided by the infant’s own mother) seemed to be a priority. Living with a girl helper did not have any measurable effect on the frequency or duration of nursing, or on the time that women spent caring for their infants. Based on these findings, hypotheses are outlined for future work on the effect of girl helpers on women’s fertility. Research for this project was funded by the Nestlé Foundation, the Harvard Anthropology Goelet Fund, and the Harvard College Research Program. Eduardo Fernandez-Duque commented on an early draft of this paper. Riley Bove (A.B., Harvard, 1998) is a research associate in the Department of Anthropology at Harvard University with research interests in intergenerational female networks and polygyny as a social mediator of women’s health (esp. urban, African). Claudia Valeggia (Ph.D., U.C. Davis, 1996) is a postdoctoral fellow in the Department of Anthropology at Harvard University with research interests in reproductive ecology and ethnopediatry. Peter Ellison (Ph.D., Harvard, 1983) is a professor of anthropology and director of the Reproductive Ecology Laboratory at Harvard University. He is the author of On Fertile Ground: Ecology, Evolution and Human Reproduction (Harvard University Press, 2001).  相似文献   

18.
Three geographically isolated populations of the giant kelp, Macrocystis pyrifera (L.) C. Ag., were examined for responses to nitrate availability in batch culture experiments using juvenile sporophytes reared from spores in the laboratory. Although maximum rates of nitrate-saturated growth were similar among groups, there were significant quantitative differences in the response to nitrate limitation that can be related to natural patterns of nutrient availability at these sites. Plants from Santa Catalina Island (most oligotrophic) achieved maximum growth rates at ambient nitrate concentrations that were lower than those for plants from Monterey Bay, California (most eutrophic), or Refugio State Beach (near Santa Barbara, California). Tissue nitrogen and amino acid concentrations were highest in plants cultured from Santa Catalina Island populations at all external nitrate concentrations, suggesting that differences in nitrate requirements for growth may reflect the efficiency of nitrate uptake and assimilation at subsaturating nitrate concentrations. Given the different physical environments from which these plants came, the data suggest that geographically isolated populations of M. pyrifera have undergone genetic divergence that can be explained by ecotypic adaptation to unique habitat conditions at these sites.  相似文献   

19.
Significant amounts of wealth have been exchanged as part of marriage settlements throughout history. Although various models have been proposed for interpreting these practices, their development over time has not been investigated systematically. In this paper we use a Bayesian MCMC phylogenetic comparative approach to reconstruct the evolution of two forms of wealth transfers at marriage, dowry and bridewealth, for 51 Indo-European cultural groups. Results indicate that dowry is more likely to have been the ancestral practice, and that a minimum of four changes to bridewealth is necessary to explain the observed distribution of the two states across the cultural groups. A preliminary version of this paper was presented at the 16th meeting of the Human Behavior and Evolution Society (HBES), Berlin 2004. Mark Pagel and Andrew Meade provided the software, the coded linguistic data, and valuable advice on their use. LF is funded by Fondazione Ing. Aldo Gini (Italy), the ESRC (UK), and the UCL Graduate School (UK). Five anonymous reviewers provided helpful comments. The authors are based at the Department of Anthropology of UCL and members of the AHRC Centre for the Evolutionary Analysis of Cultural Behaviour (CEACB). LF is studying towards a PhD, CH is a CEACB Senior Research Fellow, and RM is Professor of Evolutionary Anthropology.  相似文献   

20.
Relationship among symbiotic dinoflagellates of the genusSymbiodinium derived from seven different host species has been studied by means of DNA/DNA hybridization. DNA homologies range from about 70 to 30%D. Highest homology is regarded as subspecific level. Based on the characteristics of DNA and phenotypes,Symbiodinium microadriaticum subsp.microadriaticum is separated fromSymbiodinium microadriaticum subsp.condylactis. Lowest homology occurs at the methodical background, and is similar to that obtained with DNA of algae belonging to different classes. The data are in excellent agreement with DNA base composition, karyotypes, and morpohological as well as biochemical markers, emphasizing speciation among these gymnodinioid zooxanthellae.Dedicated to DrRobert K. Trench, Professor of Biology and Geology, University of California at Santa Barbara, whose work initiated recognition of speciation in zooxanthellae.  相似文献   

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