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PubMed2003

Heritability of parental effort in a passerine bird.

The study of the evolution of parental care is central to our understanding of social systems, sexual selection, and interindividual conflict, yet we know virtually nothing about the genetic architecture of parental care traits in natural populations. In this paper, we use data from a long term field study of a passerine bird, the long-tailed tit (Aegithalos caudatus), to examine the heritability of the rate at which parents feed offspring. This measure of effort is positively related to offspring survival, is repeatable within individuals, and does not appear to be confounded by environmental effects. Using both parent-offspring regression, and an animal model approach, with a pedigree derived from ringing data, we show that our measure of effort has a significant heritable component.

Animals↗
PubMed2002

Evolution of supercolonies: the Argentine ants of southern Europe.

Some ants have an extraordinary social organization, called unicoloniality, whereby individuals mix freely among physically separated nests. This type of social organization is not only a key attribute responsible for the ecological domination of these ants, but also an evolutionary paradox and a potential problem for kin selection theory because relatedness between nest mates is effectively zero. The introduction of the Argentine ant in Europe was apparently accompanied by a dramatic loss of inter-nest aggression and the formation of two immense supercolonies (which effectively are two unicolonial populations). Introduced populations experienced only limited loss of genetic diversity at neutral markers, indicating that the breakdown of recognition ability is unlikely to be merely due to a genetic bottleneck. Rather, we suggest that a "genetic cleansing" of recognition cues occurred after introduction. Indeed workers of the same supercolony are never aggressive to each other despite the large geographical distance and considerable genetic differentiation between sampling sites. By contrast, aggression is invariably extremely high between the two supercolonies, indicating that they have become fixed for different recognition alleles. The main supercolony, which ranges over 6,000 km from Italy to the Spanish Atlantic coast, effectively forms the largest cooperative unit ever recorded.

Aggression↗
PubMed1999

Alopecia areata, stress and psychiatric disorders: a review.

Although the results of some studies have proven negative, the influence of psychological factors in the development, evolution and therapeutic management of alopecia areata is, in general, well documented. Life events and intrapsychically generated stress can play an important role in triggering of some episodes. The comorbidity of psychiatric disorders, mainly generalized anxiety disorder, depression, and phobic states, is high. The role of treatment of concomitant psychopathological disorders is a vital one. Indeed this treatment can positively affect how the patient adapts to his/her alopecia and social setting and perhaps can even lead to a better dermatological evolution of the alopecia. Therefore, controlled studies analyzing the possible links between psychiatric symptoms, treatment with antidepressants or benzodiacepines, evolution of alopecia, medium term prognosis, and immune function are necessary. Basic psychotherapeutic support may prove to be of use in many cases and can be carried out by the dermatologist, although a subgroup of patients may need psychopharmacological or psychotherapeutic specialized treatments. Studies using operative diagnostic criteria and structured interviews are still scarce. Therefore, it seems necessary to design studies using modern psychiatric methodology. Controlled clinical trials to test the efficiency of psychoactive drugs and psychotherapy in the disease are also needed. By studying in depth these and other related aspects, we may improve the clinical management of our patients.

Alopecia Areata↗
PubMed2003

Challenging the trade-off model for the evolution of virulence: is virulence management feasible?

Progress in understanding the evolution of infectious diseases has inspired proposals to manage the evolution of pathogen (including parasite) virulence. A common view is that social interventions that lower pathogen transmission will indirectly select lower virulence because of a trade-off between transmission and virulence. Here, we argue that there is little theoretical justification and no empirical evidence for this plan. Although a trade-off model might apply to some pathogens, the mechanism appears too weak for rapid selection of substantial changes in virulence. Direct selection against virulence itself might be a more rewarding approach to managing the evolution of virulence.

Animals↗
PubMed2004

Evolution of the biopsychosocial model: prospects and challenges for health psychology.

Although advances have been made in specifying connections between biological, psychological, and social processes, the full potential of the biopsychosocial model for health psychology remains untapped. In this article, 4 areas that need to be addressed to ensure the continued evolution of the biopsychosocial model are identified and a series of recommendations concerning initiatives directed at research, training, practice and intervention, and policy are delineated. These recommendations emphasize the need to better understand and utilize linkages among biological, psychological, social, and macrocultural variables. Activities that facilitate the adoption of a multisystem, multilevel, and multivariate orientation among scientists, practitioners, and policymakers will most effectively lead to the kinds of transdisciplinary contributions envisioned by the biopsychosocial perspective.

Behavioral Medicine↗
PubMed1994

A phylogenetic analysis of soldier evolution in the aphid family Hormaphididae.

Aphid soldiers, altruistic larvae that protect the colony from predators, are an example of highly social behaviour in an insect group with a natural history different from the eusocial Hymenoptera and Isoptera. Aphids therefore allow independent tests of theory developed to explain the evolution of eusociality. Although soldiers have been discovered in five tribes from two families, the number and pattern of origins and losses of soldiers is unknown due to a lack of phylogenetic data. Here I present a mtDNA based phylogeny for the Hormaphididae, and test the hypothesis that soldiers in the tribe Cerataphidini produced during two points in the life cycle represent independent origins. The results support this hypothesis. In addition, a minimum of five evolutionary events, either four origins and one loss or five origins, are required to explain the distribution of soldiers in the family. The positions of the origins and losses are well resolved, and this phylogeny provides an historical framework for studies on the causes of soldier aphid evolution.

Animals↗
PubMed1998

[Construction and its characteristic on the concept of a 'health culture'].

Toward the 21st century, subjects and methods of hygiene and public health will be specialized and subdivided. However, practical approaches to human health need an integrated method focusing to a structure of human life. Under these circumstances, the concept of 'health culture' becomes prevalent. The role of hygiene related to the improvement of life style, the development of re-cycle system, and fulfillment of a barrier-free system focussed on the handicapped and the elderly have become increasingly important. Therefore, an increase in the recognition to the concept of 'health culture' is essential to the research of hygiene. The purpose of this paper is to make a historical and theoretical analysis of health culture', in order to promote it as the leading concept of all activities concerned with health in the 21st century. The methods of this paper are mainly historical and theoretical review. 'Health culture' was introduced in American and European societies a hundred years ago. Health culture in the USA involves knowledge and skills applied to actual daily life, refrecting pragmatism as the ideal feature of American society. In Germany, the concept of 'Hygienishe Kultur' was established at the field of social hygiene by Grotjahn and by Fischer in the early 20th century. This concept recognized the importance of the development of culture and independence of life in labour based on the evolution of the concept of 'Hygienishe Kultur'. In Japan, under the influence of German social hygiene, the social hygienic theory flourished. A social hygienist, Tetsuo Hoshino used the term 'hygienic culture' in the context of life creation toward a healthy life. Health culture is the total system concerning knowledge, experience, skill, and norms related to health, which has developed with the development of society. It has fundamental function promotes the creation of culture and self-cultivation of living man, whereas, it contributes to the realization of health based on individuality, in conjunction with the co-operation of medical and health sciences. The contemporary representation of health culture includes new health care activities such as self-care, a self-help movement, and health volunteer activities. It means the basic shift of the function of health culture is from that of life style to life movement. Nowadays, the role of hygiene in the total health care system is seriously considered. The goal, objects, and methods of hygiene should be re-evaluated under the concept of 'health culture', in order to re-define hygiene as the science for people living in a society.

Attitude to Health↗
PubMed2001

Kin recognition and the evolution of altruism.

In 1964, Hamilton formalized the idea of kin selection to explain the evolution of altruistic behaviours. Since then, numerous examples from a diverse array of taxa have shown that seemingly altruistic actions towards close relatives are a common phenomenon. Although many species use kin recognition to direct altruistic behaviours preferentially towards relatives, this important aspect of social biology is less well understood theoretically. I extend Hamilton's classic work by defining the conditions for the evolution of kin-directed altruism when recognizers are permitted to make acceptance (type I) and rejection (type II) errors in the identification of social partners with respect to kinship. The effect of errors in recognition on the evolution of kin-directed altruism depends on whether the population initially consists of unconditional altruists or non-altruists (i.e. alternative forms of non-recognizers). Factors affecting the level of these error rates themselves, their evolution and their long-term stability are discussed.

Altruism↗
PubMed2004

New perspectives in primate cognitive ecology.

The papers in this issue are from a symposium presented at the 71st Annual Meeting of the American Association of Physical Anthropologists held in Buffalo, New York, in April 2002. In the light of recent theoretical and methodological advances and debates in the study of cognition, this symposium addressed questions concerning primate cognitive ecology and decision-making from a variety of perspectives. These include ontogenetic patterns of brain growth and learning, paleoecology and evolution, sensory adaptations, foraging strategies, tool-using behavior, and concepts derived from the study of human cognition, such as schemata, planning, and rehearsal of activities. In this issue, data are presented on New World monkeys, Old World monkeys, apes, and humans. It is argued that the ability to make decisions based on the recognition that tertiary relationships in one context can be used to understand cause-and-effect relationships in an unrelated context may enable nonhuman primates to effectively reduce uncertainty and solve problems in changing social and ecological environments.

Animals↗
PubMed2002

Trade-offs in group living: transmission and disease resistance in leaf-cutting ants.

Sociality can be associated with significant costs due to the increased risk of disease transmission. However, in some organisms the costs may be offset by benefits due to improvements in defences against parasites. To examine this possible trade-off between infection risk and disease resistance, we used Acromyrmex leaf-cutting ants and the entomopathogenic fungus Metarhizium anisopliae as the model system. Ants exposed to the parasite were found to have substantially improved survival when they were kept with nest-mates, while the cost of being in a group in terms of increased disease transmission was very low. The efficiency of transmission is described by the transmission parameter, which decreased with increasing host density showing that transmission rates are inversely density dependent. Both grooming and antibiotic secretions appeared to be important in resistance against the parasite, with the defences of small workers being particularly effective. The results indicate that leaf-cutting ant colonies may have much greater resistance to disease than would be predicted from the high densities of host individuals within them. Unlike most organisms, group living in these ants may actually be associated with a net benefit in terms of disease dynamics.

Animals↗
PubMed2005

Affiliation promotes the transmission of a social custom: handclasp grooming among captive chimpanzees.

Handclasp grooming is a unique social custom, known to occur regularly among some, but not all populations of chimpanzees (Pan troglodytes). As with other cultural behaviors, it is assumed that this distinctive grooming posture is learned socially by one individual from another. However, statistical comparisons among factors thought to influence how a behavior spreads within a group have never, to our knowledge, been conducted. In the present study, the origination and spread of handclasp grooming in a group of captive chimpanzees was followed throughout more than 1,500 h of observation over a period of 12 years. We report on the frequency, bout duration, and number and demography of performers throughout the study period, and compare these findings to those reported for wild populations. We predicted that dyads with strong affiliative ties, measured by time spent in proximity to and grooming one another, were likely to develop a handclasp grooming partnership during the study period. A quadratic assignment procedure was used to compare correlations among observed frequencies of grooming and proximity with handclasp grooming in all possible dyads within the group. As predicted, the formation of new handclasp grooming dyads was positively correlated with the rate of overall grooming and proximity within a dyad. In addition, in nearly all dyads formed, at least one individual had been previously observed to handclasp groom. We concluded that affiliation and individual experience determines the transmission of handclasp grooming among captive chimpanzees.

Animals↗
PubMed2000

Hawks, doves, and mixed-symmetry games.

The hawk-dove game has proved to be an important tool for understanding the role of aggression in social interactions. Here, the game is presented in a more general form (GHD) to facilitate analyses of interactions between individuals that may differ in "size", where size is interpreted as a surrogate for resource holding power. Three different situations are considered, based on the availability and use of information that interacting individuals have about their sizes: the classical symmetric case, in which no information about sizes is used, the asymmetric case, in which the individuals know their relative sizes and thus their chances of prevailing in combat, and a mixed-symmetry case, in which each individual only knows its own size (or only knows its opponent's size). I describe and use some recently developed methods for multitype games-evolutionary games involving two or more categories of players. With these methods and others, the evolutionarily stable strategies (ESSs) that emerge for the three different cases are identified and compared. A proof of the form and uniqueness of the ESS for the mixed-symmetry case is presented. In this situation, one size category at most can play a mixed strategy; larger individuals are aggressive and smaller individuals are not. As the number of size categories approaches infinity and the size distribution becomes continuous, there is a threshold size, above which all individuals are aggressive, and below which they are not.

Aggression↗
PubMed2005

[Social aspects and cancer: information dedicated to cancer patients and relatives].

In response to the evolution of the information-seeking behaviour of patients and concerns from health professionals regarding cancer patient information, the French National Federation of Comprehensive Cancer Centres (FNCLCC) introduced, in 1998, an information and education program dedicated to patients and relatives, the SOR SAVOIR PATIENT program (SSP). The methodology of this program adheres to established quality criteria regarding the elaboration of patient information. Cancer patient information, developed in this program, is based on clinical practice guidelines produced by the FNCLCC and the twenty French regional cancer centres, the National League against Cancer, The National Cancer Institute, the French Hospital Federation, the National Oncology Federation of Regional and University Hospitals, the French Oncology Federation of General Hospitals, many learned societies, as well as an active participation of patients, former patients and caregivers. The information and dialogue handbook SOR SAVOIR PATIENT Social aspects & cancer partly published in this edition of the Bulletin du cancer, provides specific information regarding patient social rights and benefits extracted from the texts of laws currently in force in France. It also relies on the handbook A "Prévoir Demain, La réinsertion des patients traités pour cancers A", realised in partnership with the FNCLCC, the Coloplast foundation for quality of life and the National League against Cancer. This document is available from the FNCLCC (101, rue de Tolbiac, 75013 Paris, Tel. (0033) 1 44 23 04 68, www.fnclcc.fr). The handbook A "Social aspects & cancer A" was worked out and published in 2004. Information may change with new legal regulations. It is therefore strongly advised to refer to the texts of laws in force to check for possible amendments. This article aims to help patients and relatives to be better aware of their social rights, to locate the different social and administrative services concerned (CAF, Cotorep, etc.) and to turn to the right person and the appropriate agency in the event of social difficulties during and after the disease. This document is designed to offer health professionals a validated information digest of all resources available in order to better communicate with the patient on social aspects of cancer.

Family↗