Search results for " cannibalism"
showing 10 items of 11 documents
Mother and offspring fitness in an insect with maternal care: phenotypic trade-offs between egg number, egg mass and egg care
2014
Background Oviparous females have three main options to increase their reproductive success: investing into egg number, egg mass and/or egg care. Although allocating resources to either of these three components is known to shape offspring number and size, potential trade-offs among them may have key impacts on maternal and offspring fitness. Here, we tested the occurrence of phenotypic trade-offs between egg number, egg mass and maternal expenditure on egg care in the European earwig, Forficula auricularia, an insect with pre- and post-hatching forms of maternal care. In particular, we used a series of laboratory observations and experiments to investigate whether these three components no…
Sperm competition and small size advantage for males of the golden orb-web spider Nephila edulis
2000
Sexual selection, through female choice and/or male‐male competition, has influenced the nature and direction of sexual size dimorphism in numerous species. However, few studies have examined the influence of sperm competition on size dimorphism. The orb-web spider Nephila edulis has a polygamous mating system and extreme size dimorphism. Additionally, the frequency distribution of male body size is extremely skewed with most males being small and few large. The duration of copulation, male size and sexual cannibalism have been identified as the significant factors determining patterns of sperm precedence in spiders. In double mating trials, females were assigned to three treatments: either…
Costs of courtship and mating in a sexually cannibalistic orb-web spider: female mating strategies and their consequences for males
2002
The costs of courtship and mating may include increased risks of predation, the transmission of pathogens, and a loss of foraging opportunities. Thus, a female's decision to tolerate a courting male will depend upon how these costs offset the benefits of mating, which will depend on her reproductive and nutritional status. While these costs may be similar for mated and unmated females, the benefits of mating will be less for mated than virgin females. However, the cost of lost foraging opportunities may be higher for females with fewer nutritional reserves necessary for forming eggs. We examined how these costs and benefits influence the courtship and mating behaviour of male and female orb…
Sexual cannibalism in Nephila plumipes as a consequence of female life history strategies
2002
The evolution of sexual cannibalism has been modelled as both an adaptive and nonadaptive female strategy. Recent evidence from several species suggests a connection between female foraging and sexual cannibalism, but the precise benefits for females have remained obscure. Here, we investigate the difference between cannibalistic and noncannibalistic female Nephila plumipes by removing the potential nutritional benefit of cannibalism. Courting and mating males that were killed by a female were immediately removed so that the female could not consume them. Nevertheless, cannibalistic females gained more mass from maturation to oviposition and produced larger first clutches than noncannibalis…
Cannibalismo e antropopoiesi nella poesia iliadica
2010
Il contributo individua nel desiderio di cannibalismo una strategia di rappresentazione della violenza estrema nel poema dell'Iliade, che pone chi la esercita al di fuori dell'umano. In tal modo per converso il cannibalismo si rivela dispositivo antropopoietico in quanto costruisce modelli di umanità.
Female control of paternity in the sexually cannibalistic spider Argiope keyserlingi.
2000
Sexual conflict theory predicts an antagonistic coevolution, with each sex evolving adaptations and counter-adaptations to overcome a temporary dominance of the other sex over the control of paternity. Polyandry allows sexual selection to operate after mating has commenced, with male and female interests competing for control of fertilization. There are numerous examples of male control of paternity, but few studies have unambiguously revealed female control. Attributing variance in paternity to females is often difficult since male and female influences cannot be separated unambiguously. However, we show that polyandrous female orb-web spiders Argiope keserlingi (Arancidae) control the pat…
‘Non humana viscera sed centies sestertium comesse’ (Petr. Sat. 141,7): Philomela and the Cannibal Heredipetae in the Crotonian Section of Petronius’…
2013
The connection between the themes of money and death is widespread in Petronius' Satyricon, and is definitely not limited to the Cena Trimalchionis, where it has been widely examined. The aim of my paper is to consider the peculiar form that the motif takes in the Crotonian section of Petronius' Satyricon, and its connections with the mythical memory of the Procne and Philomela story. The theme of corpses dismemberment appears at the end of the episode of the shipwreck, the one immediately preceding the Crotonian section, through Encolpius' reflections on the sepultura practice and the destiny of human bodies after our death (Petronius, Satyricon 115, 6-19); the same theme closes the introd…
Eat or Be Eaten: Psychological and Bodily Violence in Michèle Roberts’s Reworking of Fairy-Tale Cannibalism
2014
This paper focuses on Robertsʼs counter-narrative “The Cookery Lesson” and the theme of fairy-tale cannibalism. While questioning the representation of the cannibalizing and the cannibalized bodies through the analysis of the sensuous language describing the desire-violence nexus, we shall take into account the ways in which the narrative form is affected in the passage from traditional fairy tale to contemporary short story, not only as concerns the representation of characters but also as regards the use of narrative voices and narrative strategies recalling the oral origins of fairy tales. At the same time, such formal choices critically re-contextualize source stories in a modern space-…
A mate to die for? A model of conditional monogyny in cannibalistic spiders.
2012
Monogynous males in various species actively limit themselves to mating with a single female in their lifetime. Whereas previous models have considered monogyny as an obligate mating strategy, here we explore the potential of monogyny to evolve as a context-specific (conditional) behavior. Using a state-dependent dynamic game model based on the biology of the cannibalistic spider Argiope bruennichi, we confirm that conditional monogyny can evolve under broad conditions, including an even sex ratio. We predict that males should make a terminal investment when mating with large, virgin females, especially if population density is low and the encounter occurs late in the season. We encourage e…
A mate to die for? A model of conditional monogyny in cannibalistic spiders
2012
Monogynous males in various species actively limit themselves to mating with a single female in their lifetime. Whereas previous models have considered monogyny as an obligate mating strategy, here we explore the potential of monogyny to evolve as a context-specific (conditional) behavior. Using a state-dependent dynamic game model based on the biology of the cannibalistic spider Argiope bruennichi, we confirm that conditional monogyny can evolve under broad conditions, including an even sex ratio. We predict that males should make a terminal investment when mating with large, virgin females, especially if population density is low and the encounter occurs late in the season. We encourage e…