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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.04.006 Byline: Jamie C. Moore (a), Darren J. Obbard (a), Caroline Reuter (b)(c), Stuart A. West (a), James M. Cook (b)(c) Abstract: Despite theoretical predictions, dishonest signalling has rarely been observed in aggressive interactions. We present evidence of such signalling in the nonpollinating fig wasp Philotrypesis sp. A ex Ficus rubiginosa. First, morphometric data indicated that an alternative 'atypical' male morph (17.8% of individuals) exists that tends to be larger in body size and has longer mandibles for a given body size than other 'typical' males. Second, behavioural observations suggested that males use mandible gape width (which depends on mandible length) as a cue to assess opponents before fights and retreat without escalating if they are unlikely to win, and, probably because their greater mandible gape width causes more opponents to retreat without escalating, that atypical males engaged in fewer fights than typical males for a given body size but had higher mating success. Third, atypical males were less likely to win fights than typical males of similar mandible length relative to opponents. In addition, we found that atypical males incur more injuries (greater receiver-dependent signal costs) than typical males of similar body size relative to rivals. We discuss the implications of our findings for future work on dishonest signalling. Author Affiliation: (a) Institute of Evolutionary Biology, University of Edinburgh, U.K. (b) Division of Biology, Imperial College, U.K. (c) School of Biological Sciences, University of Reading, U.K. Article History: Received 23 August 2008; Revised 4 November 2008; Accepted 9 April 2009 Article Note: (miscellaneous) MS. number: 08-00552R

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2008.01.018 Byline: Jamie C. Moore, Darren J. Obbard, Caroline Reuter, Stuart A. West, James M. Cook Abstract: Although theory exists concerning the types of strategies that should be used in contests over resources, empirical work explicitly testing its predictions is relatively rare. We investigated male fighting strategies in two nonpollinating fig wasp species associated with Ficus rubiginosa figs. In Sycoscapter sp. A, males did not assess each other before or during fights over mating opportunities. Instead, fights continued until the loser reached an energetic cost threshold that was positively correlated with its body size (fighting ability) and retreated. In Philotrypesis sp. B, prefight assessment was indicated, with males attacking competitively inferior rivals to remove them from the competitor pool (they then continued to do so until they reached a cost threshold that was again positively correlated with body size). Using data on species ecology, we discuss our findings with respect to theory on when different fighting strategies should evolve. We argue that the type of strategy used by a fig wasp species is determined by its relative benefits in terms of inclusive fitness. Author Affiliation: (a) Institute of Evolutionary Biology, University of Edinburgh, U.K. (a ) Division of Biology, Imperial College London, U.K. (a ) School of Biological Sciences, University of Reading, U.K. Article History: Received 5 August 2007; Revised 28 September 2007; Accepted 9 January 2008 Article Note: (miscellaneous) MS. number: 9484

We evaluate the utility of coefficients of variation of response propensities (CVs) as measures of risks of survey variable non‐response biases when monitoring survey data collection. CVs quantify variation in sample response propensities estimated given a set of auxiliary attribute covariates observed for all subjects. If auxiliary covariates and survey variables are correlated, low levels of propensity variation imply low bias risk. CVs can also be decomposed to measure associations between auxiliary covariates and propensity variation, informing collection method modifications and post‐collection adjustments to improve dataset quality. Practitioners are interested in such approaches to managing bias risks, but risk indicator performance has received little attention. We describe relationships between CVs and expected biases and how they inform quality improvements during and post‐data collection, expanding on previous work. Next, given auxiliary information from the concurrent 2011 UK census and details of interview attempts, we use CVs to quantify the representativeness of the UK Labour Force Survey dataset during data collection. Following this, we use survey data to evaluate inference based on CVs concerning survey variables with analogues measuring the same quantities among the auxiliary covariate set. Given our findings, we then offer advice on using CVs to monitor survey data collection. [ABSTRACT FROM AUTHOR]

A classic example of a mutualism is the one between fig plants (Ficus) and their specialized and obligate pollinating wasps. The wasps deposit eggs in fig ovules, which the larvae then consume. Because the wasps derive their fitness only from consumed seeds, this mutualism can persist only if the wasps are prevented from laying eggs in all ovules. The search for mechanisms that can limit oviposition and stabilize the wasp-seed conflict has spanned more than three decades. We use a simple foraging model, parameterized with data from two Ficus species, to show how fig morphology reduces oviposition rates and helps to resolve the wasp-seed conflict. We also propose additional mechanisms, based on known aspects of fig biology, which can prevent even large numbers of wasps from ovipositing in all ovules. It has been suggested that in mutualistic symbioses, the partner that controls the physical resources, in this case Ficus, ultimately controls the rate at which hosts are converted to visitors, regardless of relative evolutionary rates. Our approach provides a mechanistic implementation of this idea, with potential applications to other mutualisms and to theories of virulence.