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1.
In 2014, Brazil hosted the FIFA World Cup (FWC), whose mascot was the Brazilian Three‐banded armadillo (Tolypeutes tricinctus). In an article published in Biotropica in June 2014, we provocatively called out the Brazilian government for failing to live up to the environmental commitments made in its World Cup bid, and proposed that they should preserve 1,000 ha of the armadillo's habitat for every goal scored. At the time the paper received media coverage worldwide; here, we reflect on the experience of writing one of Biotropica's most high‐profile commentaries and the conservation outcomes of our essay. We end by providing guidance for other authors on how to harness high‐profile events for conservation action. Abstract in Portuguese is available with online material.  相似文献   

2.
We present a synopsis about the commentaries to the target article "Integrating cooperative breeding into theoretical concepts of cooperation", in which we attempted to integrate general mechanisms to explain cooperative behaviour among unrelated individuals with classic concepts to explain helping behaviour in cooperative breeders that do not invoke kin-based benefits. Here we (1) summarize the positions of the commentators concerning the main issues we raised in the target article and discuss important criticisms and extensions. (2) We relate our target article to some recent reviews on the evolution of cooperation and, (3) clarify how we use terminology with regard to cooperation and cooperative behaviour. (4) We discuss several aspects that were raised with respect to cooperative interactions including by-product mutualism, generalised reciprocity and multi-level selection and, (5) examine the alternatives to our classification scheme as proposed by some commentaries. (6) Finally, we highlight several aspects that might hinder the application of game theoretical mechanisms of cooperation in cooperatively breeding systems. Although there is broad agreement that cooperative breeding theory should be integrated within the more general concepts of cooperation, there is some debate about how this may be achieved. We conclude that the contributions in this special issue provide a fruitful first step and ample suggestions for future directions with regard to a more unified framework of cooperation in cooperative breeders.  相似文献   

3.
Shifts in phenology due to global climate change: the need for a yardstick   总被引:17,自引:0,他引:17  
Climate change has led to shifts in phenology in many species distributed widely across taxonomic groups. It is, however, unclear how we should interpret these shifts without some sort of a yardstick: a measure that will reflect how much a species should be shifting to match the change in its environment caused by climate change. Here, we assume that the shift in the phenology of a species' food abundance is, by a first approximation, an appropriate yardstick. We review the few examples that are available, ranging from birds to marine plankton. In almost all of these examples, the phenology of the focal species shifts either too little (five out of 11) or too much (three out of 11) compared to the yardstick. Thus, many species are becoming mistimed due to climate change. We urge researchers with long-term datasets on phenology to link their data with those that may serve as a yardstick, because documentation of the incidence of climate change-induced mistiming is crucial in assessing the impact of global climate change on the natural world.  相似文献   

4.
Matthews EE  Zoonens M  Engelman DM 《Cell》2006,127(3):447-450
Studying how protein transmembrane domains transmit signals across membranes is beset by unique challenges. Here, we discuss the circumstances that have led to success and reflect on what has been learned from these examples. Such efforts suggest that some of the most interesting properties of transmembrane helix interactions may be the least amenable to study by current techniques.  相似文献   

5.
The environmental variables that define a species ecological niche should be associated with the evolutionary patterns present in the adaptations that resulted from living in these conditions. Thus, when comparing across species, we can expect to find an association between phylogenetically independent phenotypic characters and ecological niche evolution. Few studies have evaluated how organismal phenotypes might mirror patterns of niche evolution if these phenotypes reflect adaptations. Doing so could contribute on the understanding of the origin and maintenance of phenotypic diversity observed in nature. Here, we show the pattern of niche evolution of the pinyon pine lineage (Pinus subsection Cembroides); then, we suggest morphological adaptations possibly related to niche divergence, and finally, we test for correlation between ecological niche and morphology. We demonstrate that niche divergence is the general pattern within the clade and that it is positively correlated with adaptation.  相似文献   

6.
Interaction of retinal image and eye velocity in motion perception   总被引:2,自引:0,他引:2  
Goltz HC  DeSouza JF  Menon RS  Tweed DB  Vilis T 《Neuron》2003,39(3):569-576
When we move our eyes, why does the world look stable even as its image flows across our retinas, and why do afterimages, which are stationary on the retinas, appear to move? Current theories say this is because we perceive motion by summation: if an object slips across the retina at r degrees/s while the eye turns at e degrees/s, the object's perceived velocity in space should be r + e. We show that activity in MT+, the visual-motion complex in human cortex, does reflect a mix of r and e rather than r alone. But we show also that, for optimal perception, r and e should not summate; rather, the signals coding e interact multiplicatively with the spatial gradient of illumination.  相似文献   

7.
Individuals value information that improves decision making. When social interactions complicate the decision process, acquiring information about others should be particularly valuable. In primate societies, kinship, dominance, and reproductive status regulate social interactions and should therefore systematically influence the value of social information, but this has never been demonstrated. Here, we show that monkeys differentially value the opportunity to acquire visual information about particular classes of social images. Male rhesus macaques sacrificed fluid for the opportunity to view female perinea and the faces of high-status monkeys but required fluid overpayment to view the faces of low-status monkeys. Social value was highly consistent across subjects, independent of particular images displayed, and only partially predictive of how long subjects chose to view each image. These data demonstrate that visual orienting decisions reflect the specific social content of visual information and provide the first experimental evidence that monkeys spontaneously discriminate images of others based on social status.  相似文献   

8.
In this editorial, we reflect on the arguments for starting a scientific society focused on research on how to improve healthcare. This society would take an inclusive approach to what constitutes healthcare. For instance, it should include mental health healthcare, treatment for substance abuse, the work of allied health professions, and preventive healthcare. The society would be open to researchers from all traditions. Thus, we take an inclusive approach to what constitutes scientific research, as long as it uses rigorous methods, is focused on improving healthcare, and aims at knowledge that can be transferred across settings. The society would primarily target scientific researchers but would invite others with an interest in this area of research, regardless of their discipline, position, field of application, or group affiliation (e.g., improvement science, behavioral medicine, knowledge translation). A society would need fruitful collaboration with related societies and organizations, which may include having combined meetings. Special links may be developed with one or more journals. A website to provide information on relevant resources, events, and training opportunities is another key activity. It would also provide a voice for the field at funding agencies, political arenas, and similar institutions. An organizational structure and financial resources are required to develop and run these activities. Our aim is to start an international debate, to discover if we can establish a shared vision across academics and stakeholders engaged with creating scientific knowledge on how to improve healthcare. We invite readers to express their views in the online questionnaire accessed by following the URL link provided at the end of the editorial.  相似文献   

9.
We critically review the use of the term “life history theory” in recent publications on evolutionary psychology, focusing on how the idea of a fast-slow continuum is deployed in that literature. We raise four issues:First, concerning plasticity, should we expect the effects of plasticity on the developmental response of a trait to mirror the effects of selection on the mean of that trait? We conclude that we should not. Do only plastic responses to harsh or unpredictable environments accelerate maturation, or are there plausible alternatives, such as nutrition? In many situations better nutrition is a plausible alternative.Second, how should we conceive of the harshness of an environment? It has several important dimensions. It could mean an increase in the mean mortality rate, a decrease in the mean growth rate or fertility rate, or increases in the variances of any of those rates. Our judgement of harshness will also be affected by the distribution of such effects across patches in space and through generations in time. The combination and distribution of effects make important differences to predictions.Third, where did the fast-slow idea come from, and how much does it explain? It was initially detected in comparisons across higher taxonomic levels, whose relevance to variation among individuals is unclear and where it fails to explain much of the variation.Fourth, what sorts of processes could generate the fast-slow pattern? Here we expand on insights mentioned earlier in passing to make clear how spatial population structure and class effects generate alternative predictions.We conclude with some thoughts on the nature of theories and research strategies and on how one might respond to empirical puzzles.  相似文献   

10.
The origin and maintenance of intraspecific variation in vocal signals is important for population divergence and speciation. Where vocalizations are transmitted by vertical cultural inheritance, similarity will reflect co-ancestry, and thus vocal divergence should reflect genetic structure. Horseshoe bats are characterized by echolocation calls dominated by a constant frequency component that is partly determined by maternal imprinting. Although previous studies showed that constant frequency calls are also influenced by some non-genetic factors, it is not known how frequency relates to genetic structure. To test this, we related constant frequency variation to genetic and non-genetic variables in the Formosan lesser horseshoe bat (Rhinolophus monoceros). Recordings of bats from across Taiwan revealed that females called at higher frequencies than males; however, we found no effect of environmental or morphological factors on call frequency. By comparison, variation showed clear population structure, with frequencies lower in the centre and east, and higher in the north and south. Within these regions, frequency divergence was directional and correlated with geographical distance, suggesting that call frequencies are subject to cultural drift. However, microsatellite clustering analysis showed that broad differences in constant frequency among populations corresponded to discontinuities in allele frequencies resulting from vicariant events. Our results provide evidence that the processes shaping genetic subdivision have concomitant consequences for divergence in echolocation call frequency.  相似文献   

11.
Efforts to advance our understanding of neurodegenerative diseases involve the creation chimeric organisms from human neural stem cells and primate embryos—known as prenatal chimeras. The existence of potential mentally complex beings with human and non-human neural apparatus raises fundamental questions as to the ethical permissibility of chimeric research and the moral status of the creatures it creates. Even as bioethicists find fewer reasons to be troubled by most types of chimeric organisms, social attitudes towards the non-human world are often influenced by religious beliefs. In this paper scholars representing eight major religious traditions provide a brief commentary on a hypothetical case concerning the development and use of prenatal human–animal chimeric primates in medical research. These commentaries reflect the plurality and complexity within and between religious discourses of our relationships with other species. Views on the moral status and permissibility of research on neural human animal chimeras vary. The authors provide an introduction to those who seek a better understanding of how faith-based perspectives might enter into biomedical ethics and public discourse towards forms of biomedical research that involves chimeric organisms.  相似文献   

12.
Comparisons of the strength and form of phenotypic selection among groups provide a powerful approach for testing adaptive hypotheses. A central and largely unaddressed issue is how fitness and phenotypes are standardized in such studies; standardization across or within groups can qualitatively change conclusions whenever mean fitness differs between groups. We briefly reviewed recent relevant literature, and found that selection studies vary widely in their scale of standardization, but few investigators motivated their rationale for chosen standardization approaches. Here, we propose that the scale at which fitness should be relativized should reflect whether selection is likely to be hard or soft; that is, the scale at which populations (or hypothetical populations in the case of a contrived experiment) are regulated. We argue that many comparative studies of selection are implicitly or explicitly focused on soft selection (i.e., frequency and density‐dependent selection). In such studies, relative fitness should preferably be calculated using within‐group means, although this approach is taken only occasionally. Related difficulties arise for the standardization of phenotypes. The appropriate scale at which standardization should take place depends on whether groups are considered to be fixed or random. We emphasize that the scale of standardization is a critical decision in empirical studies of selection that should always warrant explicit justification.  相似文献   

13.
As psychiatric genetics enters an era where gene identification is finally yielding robust, replicable genetic associations and polygenic risk scores, it is important to consider next steps and delineate how that knowledge will be applied to ultimately ameliorate suffering associated with substance use and psychiatric disorders. Much of the post‐genome‐wide association study discussion has focused on the potential of genetic information to elucidate the underlying biology and use this information for the development of more effective pharmaceutical treatments. In this review we focus on additional areas of research that should follow gene identification. By taking genetic findings into longitudinal, developmental studies, we can map the pathways by which genetic risk manifests across development, elucidating the early behavioral manifestations of risk, and studying how various environments and interventions moderate that risk across developmental stages. The delineation of risk across development will advance our understanding of mechanism, sex differences and risk and resilience processes in different racial/ethnic groups. Here, we review how the extant twin study literature can be used to guide these efforts. Together, these new lines of research will enable us to develop more informed, tailored prevention and intervention efforts.  相似文献   

14.
There is much interest in studying animal personalities but considerable debate as to how to define and evaluate them. We assessed the utility of one proposed framework while studying personality in terrestrial hermit crabs (Coenobita clypeatus). We recorded the latency of individuals to emerge from their shells over multiple trials in four unique manipulations. We used the specific testing situations within these manipulations to define two temperament categories (shyness-boldness and exploration-avoidance). Our results identified individual behavioral consistency (i.e., personality) across repeated trials of the same situations, within both categories. Additionally, we found correlations between behaviors across contexts (traits) that suggested that the crabs had behavioral syndromes. While we found some correlations between behaviors that are supposed to measure the same temperament trait, these correlations were not inevitable. Furthermore, a principal component analysis (PCA) of our data revealed new relationships between behaviors and provided the foundation for an alternate interpretation: measured behaviors may be situation-specific, and may not reflect general personality traits at all. These results suggest that more attention must be placed on how we infer personalities from standardized methods, and that we must be careful to not force our data to fit our frameworks.  相似文献   

15.
Biodiversity-ecosystem function experiments test how species diversity influences fundamental ecosystem processes. Historically, arthropod driven functions, such as herbivory and pest-control, have been thought to be influenced by direct and indirect associations among species. Although a number of studies have evaluated how plant diversity affects arthropod communities and arthropod-mediated ecosystem processes, it remains unclear whether diversity effects on arthropods are sufficiently consistent over time such that observed responses can be adequately predicted by classical hypotheses based on associational effects. By combining existing results from a long-term grassland biodiversity experiment (Jena Experiment) with new analyses, we evaluate the consistency of consumer responses within and across taxonomic, trophic, and trait-based (i.e. vertical stratification) groupings, and we consider which changes in arthropod community composition are associated with changes in consumer-mediated ecosystem functions.Overall, higher plant species richness supported more diverse and complex arthropod communities and this pattern was consistent across multiple years. Vegetation-associated arthropods responded more strongly to changes in plant species richness than ground-dwelling arthropods. Additionally, increases in plant species richness were associated with shifts in the species-abundance distributions for many, but not all taxa. For example, highly specialized consumers showed a decrease in dominance and an increase in the number of rare species with increasing plant species richness. Most ecosystem processes investigated responded to increases in plant species richness in the same way as the trophic group mediating the process, e.g. both herbivory and herbivore diversity increase with increasing plant species richness. In the Jena Experiment and other studies, inconsistencies between predictions based on classic hypotheses of associational effects and observed relationships between plant species richness and arthropod diversity likely reflect the influence of multi-trophic community dynamics and species functional trait distributions. Future research should focus on testing a broader array of mechanisms to unravel the biological processes underlying the biodiversity-ecosystem functioning relationships.  相似文献   

16.
17.
Camera traps (CTs) are an increasingly popular tool for wildlife survey and monitoring. Estimating relative abundance in unmarked species is often done using detection rate as an index of relative abundance, which assumes that detection rate has a positive linear relationship with true abundance. This assumption may be violated if movement behavior varies with density, but the degree to which movement behavior is density‐dependent across taxa is unclear. The potential confounding of population‐level relative abundance indices by movement would depend on how regularly, and by what magnitude, movement rate and home‐range size vary with density. We conducted a systematic review and meta‐analysis to quantify relationships between movement rate, home‐range size, and density, across terrestrial mammalian taxa. We then simulated animal movements and CT sampling to test the effect of contrasting movement scenarios on CT detection rate indices. Overall, movement rate and home‐range size were negatively correlated with density and positively correlated with one another. The strength of the relationships varied significantly between taxa and populations. In simulations, detection rates were related to true abundance but underestimated change, particularly for slower moving species with small home ranges. In situations where animal space use changes markedly with density, we estimate that up to thirty percent of a true change in relative abundance may be missed due to the confounding effect of movement, making trend estimation more difficult. The common assumption that movement remains constant across densities is therefore violated across a wide range of mammal species. When studying unmarked species using CT detection rates, researchers and managers should explicitly consider that such indices of relative abundance reflect both density and movement. Practitioners interpreting changes in camera detection rates should be aware that observed differences may be biased low relative to true changes in abundance. Further information on animal movement, or methods that do not depend on assumptions of density‐independent movement, may be required to make robust inferences on population trends.  相似文献   

18.
Cross-Scale Analysis of Fire Regimes   总被引:1,自引:0,他引:1  
  相似文献   

19.
1. Scientists tasked with collecting taxon richness and assemblage variation data for conservation purposes have identified biomonitoring studies as potential sources of information. This approach assumes that biodiversity patterns revealed by biomonitoring reflect those of the wider community, an assumption not thoroughly tested in riverine ecosystems. 2. We compared patterns of taxon richness and assemblage variation in an important biomonitoring group (Trichoptera) with a group with high conservation significance (Odonata) at 34 sites across three fifth‐order catchments. We also explored the effect of abundance on observed patterns by rarefying the larval Trichoptera data set. 3. Our results indicate that Trichoptera do not fully reflect site‐scale taxon richness or assemblage variation in Odonata. The magnitude of odonate assemblage variation was much greater than that of Trichoptera for one of the catchments. Odonata and Trichoptera richness was moderately correlated in two catchments, while assemblage variation was strongly correlated in another pair of catchments. However, comparisons based on rarefied data eliminated differences in the magnitude of assemblage variation and strengthened correlations in richness and assemblage variation, suggesting the lack of congruence in these measures might be due to differences in abundance among groups. Further, incomplete taxonomy may mask additional assemblage variation, particularly in Trichoptera. 4. Conservation planning in riverine ecosystems based on proxies derived from biomonitoring data should proceed cautiously until we understand how well the resulting information reflects biodiversity patterns in under‐sampled taxa and habitats. Future studies of biodiversity congruence should consider both richness and assemblage variation as each provides valuable information for conservation‐related decisions. The taxonomic resolution and relative abundance of comparison groups can potentially impact the strength, direction and statistical significance of patterns. Researchers should employ species‐level taxonomy and account for differences in abundance among groups through rarefaction where at all possible and DNA‐based taxonomy methods can support this.  相似文献   

20.
Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co‐distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo‐Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species‐specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo‐Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species.  相似文献   

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