The shape of things to come: museums in the technological landscape

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Alternative reproductive tactics and evolutionary rescue

Almost all life on earth is facing environmental change, and understanding how populations will respond to these changes is of urgent importance. One factor that is known to affect the speed by which a population can evolve when faced with changes in the environment is strong sexual selection. This increases the adaptive capacity of a population by increasing reproductive skew toward well-adapted (usually) males who will, on average, be best able to compete for matings. This effect could potentially be disrupted when males pursue alternative reproductive tactics (ARTs), whereby males within a species exhibit qualitatively different behaviors in their pursuit of matings. ARTs are diverse, but one common class is those expressed through condition-dependent polyphenism such that high-quality, well-adapted males compete aggressively for mates and low-quality, poorly adapted males attempt to acquire matings via other, nonaggressive behaviors. Here, using an individual-based modeling approach, we consider the possible impacts of ARTs on adaptation and evolutionary rescue. When the ART is simultaneous, meaning that low-quality males not only engage in contests but also pursue other tactics, adaptive capacity is reduced and evolutionary rescue, where a population avoids extinction by adapting to a changing environment, becomes less likely. This is because the use of the ART allows low-quality males to contribute more maladaptive genes to the population than would happen otherwise. When the ART is fixed, however, such that low-quality males will only use the alternative tactic and do not engage in contests, we find the opposite: adaptation happens more quickly and evolutionary rescue when the environment changes is more likely. This surprising effect is caused by an increase in the mating success of the highest quality males who face many fewer competitors in this scenario—counterintuitively, the presence of males pursuing the ART increases reproductive skew toward those males in the best condition

Morph-specific investment in testes mass in a trimorphic beetle, Proagoderus watanabei

When competition between males for mates is intense, it is common to find that some males will adopt alternative tactics for acquiring fertilizations, often involving the use of ‘sneak’ tactics whereby males avoid precopulatory contests. These alternative tactics are sometimes associated with discrete differences in male morphology, with sneak males investing less in weaponry but more in traits such as testes which may give an advantage in sperm competition. In some cases, it appears that males develop into more than two morphs, with a number of examples of tri- and even tetramorphic arthropod species being described. Here, we analyse the scaling relations of the dung beetle species Proagoderus watanabei, which expresses two distinct weapon traits: paired head horns and a pronotal horn. We find that males of this species are trimorphic, with alpha males expressing long head horns and a pronotal horn, beta males with long head horns but no pronotal horn and gamma males with short head horns only. We also find that alpha males invest relatively less in testes than do beta or gamma males, indicating that beta and gamma males in this species probably experience higher risks of sperm competition than do alphas

Winning and losing in the creative industries: an analysis of creative graduates' career opportunities across creative disciplines

Following earlier work looking at overall career difficulties and low economic rewards faced by graduates in creative disciplines, the paper takes a closer look into the different career patterns and economic performance of “Bohemian” graduates across different creative disciplines. While it is widely acknowledged in the literature that careers in the creative field tend to be unstructured, often relying on part-time work and low wages, our knowledge of how these characteristics differ across the creative industries and occupational sectors is very limited. The paper explores the different trajectory and career patterns experienced by graduates in different creative disciplinary fields and their ability to enter creative occupations. Data from the Higher Education Statistical Agency (HESA) are presented, articulating a complex picture of the reality of finding a creative occupation for creative graduates. While students of some disciplines struggle to find full-time work in the creative economy, for others full-time occupation is the norm. Geography plays a crucial role also in offering graduates opportunities in creative occupations and higher salaries. The findings are contextualised in the New Labour cultural policy framework and conclusions are drawn on whether the creative industries policy construct has hidden a very problematic reality of winners and losers in the creative economy

Blood Protein Residues on Lithic Artifacts from Two Archaeological Sites in the De Long Mountains, Northwestern Alaska

Immunological analysis of blood residues was performed on 25 lithic artifacts from two archaeological sites (DEL-166 and DEL-168) in the De Long Mountains of northwestern Alaska. Blood residues occur on five artifact types: retouched flakes; end scrapers; flake burins; bifaces; and wedge-shaped microblade cores. Fourteen (56%) of the 25 analyzed artifacts react positively to six animal antisera and to human blood. Besides human blood, identified residues include the blood of sturgeon (Acipenseridae), deer (Cervidae), rabbit (Leporidae), bear (Ursus), "cat" (Felidae) and "mouse" (Rodentia). Although the application of blood residue analysis to archaeological problems is a relatively new application of an old forensic method, it may provide useful information about artifact function and animal procurement from sites where faunal remains are not preserved.On a procédé à une analyse immunologique de résidus sanguins sur 25 artefacts lithiques provenant de deux sites archéologiques (DEL-166 et DEL-168) dans les monts De Long du nord-ouest de l'Alaska. On a trouvé des résidus sanguins sur cinq types d'artefacts: éclats retouchés; grattoirs sur lame; burins faits d'éclats; bifaces; et nucléus microlames cunéiformes. Quatorze (56 p. cent) des 25 artefacts analysés ont réagi positivement à six antisérums de provenance animale et à du sang humain. Outre le sang de provenance humaine, les résidus identifiés comprennent le sang d'esturgeon (Acipenseridae), de chevreuil (Cervidae), de lapin (Leporidae), d'ours (Ursus), de «chat» (Felidae) et de «souris» (Rodentia). Bien que l'application de l'analyse de résidus sanguins à des questions d'ordre archéologique soit une application relativement nouvelle d'une ancienne méthode médico-légale, elle peut fournir des renseignements utiles sur la fonction de l'artefact et sur l'approvisionnement en animaux dans les cas de sites où les vestiges de la faune n'ont pas été conservés

Sex ratio distorting microbes exacerbate arthropod extinction risk in variable environments

Maternally-inherited sex ratio distorting microbes (SRDMs) are common among arthropod species. Typically, these microbes cause female-biased sex ratios in host broods, either by; killing male offspring, feminising male offspring, or inducing parthenogenesis. As a result, infected populations can experience drastic ecological and evolutionary change. The mechanism by which SRDMs operate is likely to alter their impact on host evolutionary ecology; despite this, the current literature is heavily biased towards a single mechanism of sex ratio distortion, male-killing. Furthermore, amidst the growing concerns surrounding the loss of arthropod diversity, research into the impact of SRDMs on the viability of arthropod populations is generally lacking. In this study, using a theoretical approach, we model the epidemiology of an understudied mechanism of microbially-induced sex ratio distortion—feminisation—to ask an understudied question—how do SRDMs impact extinction risk in a changing environment? We constructed an individual-based model and measured host population extinction risk under various environmental and epidemiological scenarios. We also used our model to identify the precise mechanism modulating extinction. We find that the presence of feminisers increases host population extinction risk, an effect that is exacerbated in highly variable environments. We also identified transmission rate as the dominant epidemiological trait responsible for driving extinction. Finally, our model shows that sex ratio skew is the mechanism driving extinction. We highlight feminisers and, more broadly, SRDMs as important determinants of the resilience of arthropod populations to environmental change

Using Item Response Theory to Improve Locally-Constructed Multiple Choice Tests: Measuring Knowledge Gains and Curricular Effectiveness

Current science education reform efforts emphasize teaching K-12 science using hands-on, inquiry activities. For maximum learning and probability of implementation among inservice teachers, these strategies must be modeled in college science courses for preservice teachers. About a decade ago, Morehead State University revised their science content courses to follow an inquiry approach. As part of the courses’ assessment, a locally-made, diagnostic pre- and post-test was prepared. The main purpose of this “ex post facto” study was to demonstrate how concepts from Item Response Theory can be used to detect and remove psychometrically faulty items, and how the remaining items can be used by teachers to determine science learning gains in an inquiry-based physical science course that implemented two different curricula, “Physics and Everyday Thinking” and “Interactions in Physical Science”

Enhanced Spontaneous Emission Into The Mode Of A Cavity QED System

We study the light generated by spontaneous emission into a mode of a cavity QED system under weak excitation of the orthogonally polarized mode. Operating in the intermediate regime of cavity QED with comparable coherent and decoherent coupling constants, we find an enhancement of the emission into the undriven cavity mode by more than a factor of 18.5 over that expected by the solid angle subtended by the mode. A model that incorporates three atomic levels and two polarization modes quantitatively explains the observations.Comment: 9 pages, 2 figures, to appear in May 2007 Optics Letter

Foundation and empire : a critique of Hardt and Negri

In this article, Thompson complements recent critiques of Hardt and Negri's Empire (see Finn Bowring in Capital and Class, no. 83) using the tools of labour process theory to critique the political economy of Empire, and to note its unfortunate similarities to conventional theories of the knowledge economy