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531.
The vertebrate brain is a remarkably plastic organ, which responds quickly to environmental changes. However, to date, studies investigating plasticity in brain morphology have focused mostly on the physical properties of the surrounding environment, and little is known about brain plasticity in response to the social environment. Moreover, sex differences in brain plasticity remain virtually unexplored. Here, we tested how the social environment influenced brain morphology in adult males and females using experimental manipulation of the sex composition of social pairs (same sex vs. mixed sex) in the guppy (Poecilia reticulata). We detected substantial sex-specific plasticity in both the overall brain size (controlling for body size) and separate brain structures. The brain size was larger in males that interacted with females, and female optic tectum was larger in female-only groups. Overall, females had larger olfactory bulbs and cerebellum in comparison to males. While net sexual dimorphism in the brain structure can be explained in light of the known differences in boldness and foraging behaviour between the sexes, our results also support that cognitive demands associated with courtship behaviour can lead to plastic changes in the brain size. Our findings demonstrate that not only social environment can generate rapid, plastic responses in the vertebrate brain but also that such responses can depend strongly on sex.  相似文献   
532.
A numerical model BAEROSOL for solving the general dynamic equation (GDE) of aerosols is presented. The goal was to model the capture of volatilized metals by sorbents under incinerator-like conditions. The model is based on algorithms presented by Jacobson and Turco [Aerosol Science and Technology 22 (1995) 73]. A hybrid size bin was used to model growth and formation of particles from the continuum phase and the coagulation of existing particles. Condensation and evaporation growth were calculated in a moving size bin approach, where coagulation and nucleation was modeled in the fixed size bin model of the hybrid grid. To account for the thermodynamic equilibrium in the gas phase, a thermodynamic equilibrium code CET89 was implemented. The particle size distribution (PSD) calculated with the model was then compared to analytical solutions provided for growth, coagulation and both combined. Finally, experimental findings by Rodriguez and Hall [Waste Management 21 (2001) 589-607] were compared to the PSD predicted by the developed model and the applicability of the model under incineration conditions is discussed.  相似文献   
533.
The thylacine (Thylacinus cynocephalus), one of Australia's most characteristic megafauna, was the largest marsupial carnivore until hunting, and potentially disease, drove it to extinction in 1936. Although thylacines were restricted to Tasmania for 2 millennia prior to their extinction, recent so‐called plausible sightings on the Cape York Peninsula in northern Queensland have emerged, leading some to speculate the species may have persisted undetected. We compiled a data set that included physical evidence, expert‐validated sightings, and unconfirmed sightings up to the present day and implemented a range of extinction models (focusing on a Bayesian approach that incorporates all 3 types of data by modeling valid and invalid sightings as independent processes) to evaluate the likelihood of the thylacine's persistence. Although the last captive individual died in September 1936, our results suggested that the most likely extinction date would be 1940. Our other extinction models estimated the thylacine's extinction date between 1936 and 1943, and the most optimistic scenario indicated that the species did not persist beyond 1956. The search for the thylacine, much like similar efforts to rediscover other recently extinct charismatic taxa, is likely to be fruitless, especially given that persistence on Tasmania would have been no guarantee the species could reappear in regions that had been unoccupied for millennia. The search for the thylacine may become a rallying point for conservation and wildlife biology and could indirectly help fund and support critical research in understudied areas such as Cape York. However, our results suggest that attempts to rediscover the thylacine will be unsuccessful and that the continued survival of the thylacine is entirely implausible based on most current mathematical theories of extinction.  相似文献   
534.
Controlling invasive species presents a public-good dilemma. Although environmental, social, and economic benefits of control accrue to society, costs are borne by only a few individuals and organizations. For decades, policy makers have used incentives and sanctions to encourage or coerce individual actors to contribute to the public good, with limited success. Diverse, subnational efforts to collectively manage invasive plants, insects, and animals provide effective alternatives to traditional command-and-control approaches. Despite this work, there has been little systematic evaluation of collective efforts to determine whether there are consistent principles underpinning success. We reviewed 32 studies to identify the extent to which collective-action theories from related agricultural and environmental fields explain collaborative invasive species management approaches; describe and differentiate emergent invasive species collective-action efforts; and provide guidance on how to enable more collaborative approaches to invasive species management. We identified 4 types of collective action aimed at invasive species—externally led, community led, comanaged, and organizational coalitions—that provide blueprints for future invasive species management. Existing collective-action theories could explain the importance attributed to developing shared knowledge of the social-ecological system and the need for social capital. Yet, collection action on invasive species requires different types of monitoring, sanctions, and boundary definitions. We argue that future government policies can benefit from establishing flexible boundaries that encourage social learning and enable colocated individuals and organizations to identify common goals, pool resources, and coordinate efforts.  相似文献   
535.
Regional Environmental Change - Protection of natural or semi-natural ecosystems is an important part of societal strategies for maintaining biodiversity, ecosystem services, and achieving overall...  相似文献   
536.
Workplace resilience is a necessity for organizations and employees given it assists them in overcoming adversity and ultimately succeeding. However, organizational scholars have largely overlooked this construct. In this Incubator, we briefly summarize extant research on workplace resilience to highlight opportunities for theory building and advancement of empirical research. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
537.
Regional Environmental Change - This paper reviews the current knowledge of climatic risks and impacts in South Asia associated with anthropogenic warming levels of 1.5–4 °C...  相似文献   
538.
539.
The endemic South American mammals Meridiolestida, considered previously as dryolestoid cladotherians, are found to be non-cladotherian trechnotherians related to spalacotheriid symmetrodontans based on a parsimony analysis of 137 morphological characters among 44 taxa. Spalacotheriidae is the sister taxon to Meridiolestida, and the latter clade is derived from a primitive spalacolestine that migrated to South America from North America at the beginning of the Late Cretaceous. Meridiolestida survived until the early Paleocene (Peligrotherium) and early Miocene (Necrolestes) in South America, and their extinction is probably linked to the increasing competition with metatherian and eutherian tribosphenic mammals. The clade Meridiolestida plus Spalacotheriidae is the sister taxon to Cladotheria and forms a new clade Alethinotheria. Alethinotheria and its sister taxon Zhangheotheria, new clade (Zhangheotheriidae plus basal taxa), comprise Trechnotheria. Cladotheria is divided into Zatheria (plus stem taxa, including Amphitherium) and Dryolestida, including Dryolestidae and a paraphyletic array of basal dryolestidans (formerly classified as “Paurodontidae”). The South American Vincelestes and Groebertherium are basal dryolestidans.  相似文献   
540.
A new mammal family, Olseniidae, is proposed based on a complete foot skeleton of cf. Olsenia sp. from the Eocene Toru Ajgyr locality in Kyrgyzstan and an astragalus of Olsenia mira from the Eocene Shara Murun locality in northern China. The new form cf. Olsenia sp. is an early ungulate that combines characteristics of mesonychids, perissodactyls and artiodactyls: tetradactyl and paraxonic foot, terminal phalanges claw-like but not fissured, astragalus with shallow proximal caput and without distal trochlea. This unique character set fills a gap in the fossil record and gives insights into the ungulate phylogeny, which is still not completely understood.  相似文献   
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