20 research outputs found

    Phylogenetic Codivergence Supports Coevolution of Mimetic Heliconius Butterflies

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    The unpalatable and warning-patterned butterflies _Heliconius erato_ and _Heliconius melpomene_ provide the best studied example of mutualistic Müllerian mimicry, thought – but rarely demonstrated – to promote coevolution. Some of the strongest available evidence for coevolution comes from phylogenetic codivergence, the parallel divergence of ecologically associated lineages. Early evolutionary reconstructions suggested codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and this was initially hailed as the most striking known case of coevolution. However, subsequent molecular phylogenetic analyses found discrepancies in phylogenetic branching patterns and timing (topological and temporal incongruence) that argued against codivergence. We present the first explicit cophylogenetic test of codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and re-examine the timing of these radiations. We find statistically significant topological congruence between multilocus coalescent population phylogenies of _H. erato_ and _H. melpomene_, supporting repeated codivergence of mimetic populations. Divergence time estimates, based on a Bayesian coalescent model, suggest that the evolutionary radiations of _H. erato_ and _H. melpomene_ occurred over the same time period, and are compatible with a series of temporally congruent codivergence events. This evidence supports a history of reciprocal coevolution between Müllerian co-mimics characterised by phylogenetic codivergence and parallel phenotypic change

    On Reciprocal Causation in the Evolutionary Process

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    Past Atmospheric Deposition of Metals in Northern Indiana Measured in a Peat Core from Cowles Bog

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    A peat core from a calcareous fen was used to assess past metal accumulation from atmospheric sources in northern Indiana. Total concentrations of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn were measured at intervals along the core, which were dated by 210Pb, radiocarbon, and pollen analysis. The deposition of airborne metal particulates rose dramatically from presettlement levels as industrialization occurred upwind, with accumulation rates for some metals increasing by 2 orders of magnitude. Recent accumulation rates are about half of the peak rates of the 1970s, presumably because of emission controls and reduced production. This study, the first such record from a calcareous fen, should be less affected by postdepositional mobility than records from acidic peatlands. This method of retrospective, long-term monitoring of airborne particulates can be applied in many areas lacking such records. © 1990, American Chemical Society. All rights reserved

    Effectiveness of botulinum toxin injection in the treatment of de novo OAB symptoms following midurethral sling surgery

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    Introduction and hypothesis Intravesical onabotulinumtoxinA (Botox®) is effective for idiopathic overactive bladder (OAB) symptoms. Our primary objective was to compare the efficacy of onabotulinumtoxinA for women with de novo OAB after midurethral sling (MUS) surgery and women with idiopathic OAB. Methods Women enrolled in this prospective study had idiopathic (n=53) or de novo (n=49) OAB symptoms after MUS, with at least one episode of urgency urine incontinence per day. OnabotulinumtoxinA (100 U) was administered in 20 intradetrusor injections. Postvoid residual volumes were checked at 2, 4 and 12 weeks. Participants completed a 3- day bladder diary and the King’s Health Questionnaire (KHQ) before and 12 weeks after treatment. Results After 12 weeks, 22 patients (41.5 %) in the idiopathic OAB and 19 patients (38.8 %) in the de novo OAB groups were completely dry. OnabotulinumtoxinA injections had a significant benefit within both groups (p 90 ml in both groups. Urinary retention was observed in four patients. Conclusions We observed similar improvement in OAB symptoms after intravesical onabotulinumtoxinA injections within both groups. The rates of retention and requirement for catheterization even for women with a prior MUS were acceptable. These observational data provide evidence that onabotulinumtoxinA can effectively treat patients with OAB following stress urinary incontinence surger
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