Is being a doctor still fun?

Over the past two decades, a decline in physician job and career satisfaction has been reported. This study was developed to determine the current state of physician satisfaction and to define factors correlated with overall satisfaction. We mailed a survey to 406 physicians in Solano County, California. Responses were anonymous, and data were analyzed by several methods. Of the 406 physicians, 251 (62%) responded. Most respondents were satisfied with their jobs (80%). The vast majority felt good about their ability to help their patients (92%), enjoyed the relationships they had with patients (93%) and colleagues (86%), and found their work intellectually satisfying (89%). Nearly two thirds (63%) of respondents thought their job was "fun." This ability to derive great pleasure from work showed the strongest correlation with overall satisfaction. Overall satisfaction did not differ between primary care and non-primary care physicians or between physicians in a large health maintenance organization and those in mostly solo and small-group fee-for-service practices. Despite substantial challenges to physician morale and autonomy, most responding physicians in our study continued to enjoy overall job satisfaction, and a solid majority thought that their work was fun.     

Is the matrix a sea? Habitat specificity in a naturally fragmented landscape

Abstract.  1. Metapopulation and island biogeography theory assume that landscapes consist of habitat patches set in a matrix of non-habitat. If only a small proportion of species conform to the patch–matrix assumptions then metapopulation theory may only describe special cases rather than being of more general ecological importance.
2. As an initial step towards understanding the prevalence of metapopulation dynamics in a naturally fragmented landscape, the distribution of beetle species in three replicates of three habitat types was examined, including rainforest and eucalypt forest (the habitat patches), and buttongrass sedgeland (the matrix), in south-west Tasmania, Australia.
3. Ordination methods indicated that the buttongrass fauna was extremely divergent from the fauna of forested habitats. Permutation tests showed that the abundance of 13 of 17 commonly captured species varied significantly among habitats, with eight species confined to eucalypts or rainforest, and three species found only in buttongrass. Approximately 60% of species were confined to forested habitat implying that metapopulation theory has the potential to be very important in the forest–buttongrass landscape.
4. Although floristically the rainforest and eucalypts were extremely distinct, the beetle faunas from eucalypts and rainforests overlapped substantially. Therefore rainforest patches connected by eucalypt forest represent continuous habitat for most species.
5. Other studies report a wide range of values for the proportion of patch-specific species in fragmented landscapes. Understanding the environmental or historical conditions under which a high proportion of species become patch specialists would help to identify where spatial dynamic theory may be especially applicable, and where habitat loss and fragmentation poses the greatest threat to biodiversity.     

Is culture a golden barrier between human and chimpanzee?

Culture pervades much of human existence. Its significance to human social interaction and cognitive development has convinced some researchers that the phenomenon and its underlying mechanisms represent a defining criterion for humankind. However, care should be taken not to make hasty conclusions in light of the growing number of observations on the cultural abilities of different species, ranging from chimpanzees and orangutans to whales and dolphins. The present review concentrates on wild chimpanzees and shows that they all possess an extensive cultural repertoire. In the light of what we know from humans, I evaluate the importance of social learning leading to acquisition of cultural traits, as well as of collective meaning of communicative traits. Taking into account cross‐cultural variations in humans, I argue that the cultural abilities we observe in wild chimpanzees present a broad level of similarity between the two species.     

Is there such a thing as landscape genetics?

For a scientific discipline to be interdisciplinary, it must satisfy two conditions; it must consist of contributions from at least two existing disciplines, and it must be able to provide insights, through this interaction, that neither progenitor discipline could address. In this study, I examine the complete body of peer‐reviewed literature self‐identified as landscape genetics (LG) using the statistical approaches of text mining and natural language processing. The goal here was to quantify the kinds of questions being addressed in LG studies, the ways in which questions are evaluated mechanistically, and how they are differentiated from the progenitor disciplines of landscape ecology and population genetics. I then circumscribe the main factions within published LG studies examining the extent to which emergent questions are being addressed and highlighting a deep bifurcation between existing individual‐ and population‐based approaches. I close by providing some suggestions on where theoretical and analytical work is needed if LGs is to serve as a real bridge connecting evolution and ecology sensu lato.     

The evolution of comparative cognition: Is the snark still a boojum?

In “The Snark is a Boojum”, Beach [Beach, F.A., 1950. The snark was a boojum. American Psychologist. 5, 115–124] famously asserted that animal psychology embraced too few species and too few problems to deserve the name comparative. Later in the 20th century, others [e.g. Kamil, A.C., 1988. A synthetic approach to the study of animal intelligence. In: Leger, D.W. (Ed.), Comparative Perspectives in Modern Psychology. Nebraska Symposium on Motivation, vol. 35. University of Nebraska Press, Lincoln, NE, pp. 230–257; Shettleworth, S.J., 1993. Where is the comparison in comparative cognition? Alternative research programs. Psychological Science. 4, 179–184] expressed similar concerns about the new subfield of comparative cognition, suggesting that a more biological approach to choice of species and problems was needed to balance a dominant anthropocentrism. The last 10–15 years have seen many new developments, and a recent survey like Beach’s reveals a very different picture. Not only are many more species being studied, contributions by researchers from different backgrounds are increasing, and research on comparative cognition is better connected with developmental psychology, behavioral neuroscience, primatology, behavioral ecology, and other fields. Contemporary research addresses three major aspects of cognition about equally: basic processes, physical cognition, and social cognition. This article describes a selected research program from each area, chosen to exemplify current trends and challenges for the field.     

Is the matrix really inhospitable? Vole runway distribution in an experimentally fragmented landscape

Habitat fragmentation is a common feature of modern landscapes, with significant impacts on the population densities of and space use by animals. A frequent model system for studying these effects is that of voles ( Microtus spp.) and other rodents in experimentally fragmented grasslands. Design of these study sites is motivated by landscape theory, and often assumes that the matrix between discrete experimental habitat patches is inhospitable to focal species. Our census of M. ochrogaster runways in an experimentally fragmented landscape in eastern Kansas indicates that voles make substantial use of the mowed matrix, and that such use increases with degree of habitat fragmentation. Census season (winter, summer) was also an important predictor of observed runway distributions. Our results suggest that voles may have home ranges that include multiple small fragments and also the intervening matrix, leading to overestimates of population density. While the assumption that the matrix is inhospitable in experimentally fragmented habitats may be justified in many cases, studies using the model system of Microtus spp. or ecologically similar rodents in grasslands should incorporate methods that account for use of the matrix.     

Is adult cardiac myocyte still able to proliferate?

Adult cardiac myocytes do not divide anymore. Mechanically overloaded hearts undergo hypertrophy and then fail. Cardiac hypertrophy is mainly caused by myocyte hypertrophy without myocyte proliferation, except during end-stage heart failure. By contrast, non muscular myocardial cells, such as the endothelial cells of the vessels, not only hypertrophy but are also able to proliferate. Recent works have suggested that these new cells are likely to be progenitor cells originating from bone marrow or vascular endothelium. These cells may form chimeras in the donor heart following heart transplantation. It is possible to mimic such an adaptative process by injecting progenitor cells either within the myocardium, or through the coronary circulation. Two type of cells have been utilised so far, namely bone marrow cells and myoblasts (or satellite cells) from skeletal muscles. The first clinical applications after myocardial infarction have been recently reported and showed the safety of the procedure and the possibility of improving myocardial function.     

Is gibbon ape leukaemia virus still a threat?

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Does the central dogma still stand?

ABSTRACT: Prions are agents of analog, protein conformation-based inheritance that can confer beneficial phenotypes to cells, especially under stress. Combined with genetic variation, prion-mediated inheritance can be channeled into prion-independent genomic inheritance. Latest screening shows that prions are common, at least in fungi. Thus, there is non-negligible flow of information from proteins to the genome in modern cells, in a direct violation of the Central Dogma of molecular biology. The prion-mediated heredity that violates the Central Dogma appears to be a specific, most radical manifestation of the widespread assimilation of protein (epigenetic) variation into genetic variation. The epigenetic variation precedes and facilitates genetic adaptation through a general 'look-ahead effect' of phenotypic mutations. This direction of the information flow is likely to be one of the important routes of environment-genome interaction and could substantially contribute to the evolution of complex adaptive traits.ReviewersThis article was reviewed by Jerzy Jurka, Pierre Pontarotti and Juergen Brosius. For the complete reviews, see the Reviewers' Reports section.     

The end of the adaptive landscape metaphor?

The concepts of adaptive/fitness landscapes and adaptive peaks are a central part of much of contemporary evolutionary biology; the concepts are introduced in introductory texts, developed in more detail in graduate-level treatments, and are used extensively in papers published in the major journals in the field. The appeal of visualizing the process of evolution in terms of the movement of populations on such landscapes is very strong; as one becomes familiar with the metaphor, one often develops the feeling that it is possible to gain deep insights into evolution by thinking about the movement of populations on landscapes consisting of adaptive valleys and peaks. But, since Wright first introduced the metaphor in 1932, the metaphor has been the subject of persistent confusion, from equivocation over just what the features of the landscape are meant to represent to how we ought to expect the landscapes to look. Recent advances—conceptual, empirical, and computational—have pointed towards the inadequacy and indeed incoherence of the landscapes as usually pictured. I argue that attempts to reform the metaphor are misguided; it is time to give up the pictorial metaphor of the landscape entirely and rely instead on the results of formal modeling, however difficult such results are to understand in ‘intuitive’ terms.