Publications by authors named "Maria Almbro"

Sexual selection is argued to be important for the removal of deleterious mutations, promoting population fitness, accelerating adaptation, and compensating for the two-fold cost of sex. Here we induced mutations in the dung beetle Onthophagus taurus using ionizing radiation, and tested the efficacy of sexual selection in their removal. Mutations reduced male precopulatory (strength) and postcopulatory (testes mass) sexual traits.

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Male reproductive success is influenced by competitive interactions during precopulatory and postcopulatory selective episodes. Consequently, males can gain reproductive advantages during precopulatory contest competition by investing in weaponry and during postcopulatory sperm competition by investing in ejaculates. However, recent theory predicts male expenditure on weaponry and ejaculates should be subject to a trade-off, and should vary under increasing risk and intensity of sperm competition.

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In numerous species, egg chemoattractants play a critical role in guiding sperm towards unfertilized eggs (sperm chemotaxis). Until now, the known functions of sperm chemotaxis include increasing the effective target size of eggs, thereby promoting sperm-egg encounters, and facilitating species recognition. Here, we report that in the broadcast spawning mussel, Mytilus galloprovincialis, egg chemoattractants may play an unforeseen role in sexual selection by enabling sperm to effectively 'choose' between the eggs of different conspecific females.

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Sperm are particularly prone to oxidative damage because they generate reactive oxygen species (ROS), have a high polyunsaturated fat content and a reduced capacity to repair DNA damage. The dietary compounds vitamin E and beta-carotene are argued to have antioxidant properties that help to counter the damaging effects of excess ROS. Here in, we tested the post-copulatory consequences for male crickets (Teleogryllus oceanicus) of dietary intake of these two candidate antioxidants.

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For an animal to escape an attacking predator, speed and manoeuvrability are likely to be crucial factors. Previous studies on reptiles and birds have revealed that gaining weight, due to for instance egg load or lipid accumulation, leads to impaired escape ability and possibly increases the risk of being caught by predators. Here we tested whether the flight performance of an insect, the small tortoiseshell butterfly (Aglais urticae), is affected by variations in body mass due to feeding by comparing flight performance parameters between individuals that (i) took flight spontaneously or after being subjected to a simulated predator attack and (ii) varied in flight muscle ratio (FMR: thorax mass/total body mass).

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