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Our view of sperm competition is largely shaped by game-theoretic models based on external fertilizers. External fertilization is of particular interest as it is the ancestral mode of reproduction and as such, relevant to the evolution and maintenance of anisogamy (i.e., large eggs and tiny, numerous sperm). Current game-theoretic models have been invaluable in generating predictions of male responses to sperm competition in a range of internal fertilizers but these models are less relevant to marine broadcast spawners, the most common and archetypal external fertilizers. Broadcast spawners typically have incomplete fertilization due to sperm limitation and/or polyspermy (too many sperm), but the effects of incomplete (<100% fertilization rates) fertilization on game-theoretic predictions are unclear particular with regards to polyspermy. We show that incorporating the effects of sperm concentration on fertilization success changes the predictions of a classic game-theoretic model, dramatically reversing the relationship between sperm competition and the evolutionarily stable sperm release strategy. Furthermore, our results suggest that male and female broadcast spawners are likely to be in conflict at both ends of the sperm environment continuum rather than only in conditions of excess sperm as previously thought. Across the majority of the parameter space we explored, males release either too little to too much sperm for females to achieve complete fertilization. This conflict could result in a coevolutionary race that may have led to the evolution of internal fertilization in marine organisms. [ABSTRACT FROM AUTHOR]

Nature conservation is underresourced, requiring managers to prioritize where, when, and how to spend limited funds. Prioritization methods identify the subset of actions that provide the most benefit to an actor's objective. However, spending decisions by conservation actors are often misaligned with their objectives. Although this misalignment is frequently attributed to poor choices by the actors, we argue that it can also be a byproduct of working alongside other organizations. Using strategic analyses of multi-actor systems in conservation, we show how interactions among multiple conservation actors can create misalignment between the spending and objectives of individual actors and why current uncoordinated prioritizations lead to fewer conservation objectives achieved for individual actors. We draw three conclusions from our results. First, that misalignment is an unsuitable metric for evaluating spending, because it may be necessary to achieve actors' objectives. Second, that current prioritization methods cannot identify optimal decisions (as they purport to do), because they do not incorporate other actors' decisions. Third, that practical steps can be taken to move actors in the direction of coordination and thereby better achieve their conservation objectives. [ABSTRACT FROM AUTHOR]

From: Prof. Michael F Bode, Liverpool John Moores University [ABSTRACT FROM AUTHOR]

We examine four high-resolution reflection grating spectrometers (RGS) spectra of the February 2009 outburst of the luminous recurrent nova LMC 2009a. They were very complex and rich in intricate absorption and emission features. The continuum was consistent with a dominant component originating in the atmosphere of a shell burning white dwarf (WD) with peak effective temperature between 810 000 K and a million K, and mass in the 1.2–1.4 M⊙ range. A moderate blue shift of the absorption features of a few hundred km s−1 can be explained with a residual nova wind depleting the WD surface at a rate of about 10−8 M⊙ yr−1. The emission spectrum seems to be due to both photoionization and shock ionization in the ejecta. The supersoft X-ray flux was irregularly variable on time-scales of hours, with decreasing amplitude of the variability. We find that both the period and the amplitude of another, already known 33.3-s modulation varied within time-scales of hours. We compared N LMC 2009a with other Magellanic Clouds novae, including four serendipitously discovered as supersoft X-ray sources (SSS) among 13 observed within 16 yr after the eruption. The new detected targets were much less luminous than expected: we suggest that they were partially obscured by the accretion disc. Lack of SSS detections in the Magellanic Clouds novae more than 5.5 yr after the eruption constrains the average duration of the nuclear burning phase. [ABSTRACT FROM AUTHOR]