Search results for "Animal"
showing 10 items of 22159 documents
Induction of radiata pine somatic embryogenesis at high temperatures provokes a long-term decrease in dna methylation/hydroxymethylation and differen…
2020
Based on the hypothesis that embryo development is a crucial stage for the formation of stable epigenetic marks that could modulate the behaviour of the resulting plants, in this study, radiata pine somatic embryogenesis was induced at high temperatures (23 °
Parameterising a public good: how experiments on predation can be used to predict cheat frequencies
2016
Chemical defence is superficially easy to understand as a means for individuals to protect themselves from enemies. The evolution of chemical defence is however potentially complex because such defences may cause the generation of a public good, protecting members of the population as a whole as well as individuals that deploy toxins defensively. If a public good of protection exists, it may be exploited and degraded by “cheats” that do not invest in defence. This can in turn lead to complex frequency (and density) dependent effects in toxin evolution. To investigate this we used ecologically relevant predators (Great tits, Parus major) and examined how individual and public benefits vary d…
Female sexual signaling in a capital breeder, the European glow-worm Lampyris noctiluca
2021
AbstractTheory predicts that because costs constrain female sexual signaling, females are expected to have a low signaling effort that is increased with passing time until mating is secured. This pattern of signaling is expected to result from females balancing the costs associated with a higher than optimal signaling effort and those costs associated with a low signaling effort that increase the likelihood of delayed mating. We tested whether this prediction applies in the common glow-worm Lampyris noctiluca (Coleoptera, Lampyridae), a capital breeding species in which females glow at night to attract males. Contrary to predictions, we found that the duration of female sexual signaling sig…
Learned parasite avoidance is driven by host personality and resistance to infection in a fish-trematode interaction
2016
Cognitive abilities related to the assessment of risk improve survival. While earlier studies have examined the ability of animals to learn to avoid predators, learned parasite avoidance has received little interest. In a series of behavioural trials with the trematode parasite Diplostomum pseudospathaceum , we asked whether sea trout ( Salmo trutta trutta ) hosts show associative learning in the context of parasitism and if so, whether learning capacity is related to the likelihood of infection mediated through host personality and resistance. We show that animals are capable of learning to avoid visual cues associated with the presence of parasites. However, avoidance behaviour ceased af…
Taxonomic status and epidemiology of the mesoparasitic copepod Pennella balaenoptera in cetaceans from the western Mediterranean.
2018
Pennella balaenoptera is a mesoparasitic copepod that has been reported in at least 17 cetacean species. Subtle morphological differences in the first antennae of adult females have been used to discriminate this species from P. filosa, a species infecting fishes. Other morphological traits are unreliable because of their high plasticity, and no molecular data are available to confirm the taxonomic status of P. balaenoptera as an independent species. We found no consistent morphological differences of the first antennae between P. balaenoptera and P. filosa collected from cetaceans and fish in the western Mediterranean. Molecular data on the mitochondrial cytochrome oxidase subunit I failed…
Pesticide-induced changes in personality depend on the urbanization level
2017
Globally increasing urbanization causes major anthropogenic changes in ecosystems, drastically altering phenotypes of organisms. Increased contamination is a well-known result of urbanization, and its effect on behaviour has been extensively studied. Yet, animal personality, consistent behavioural variation between individuals, has rarely been investigated in the context of anthropogenic contaminants. Changes in personalities may affect the viability of populations, and even alter community dynamics. We investigated the effects of exposure to a sublethal dose of the commonly used pesticide esfenvalerate on two personality traits, activity and boldness, and compared these effects between rep…
The phylogenetic relationships of Przevalski's FinchUrocynchramus pylzowi, the most ancient Tibetan endemic passerine known to date
2016
Competing systematic hypotheses have placed the Tibetan endemic Przevalski's Finch Urocynchramus pylzowi either with the Old World buntings (Emberizidae) or with the cardueline finches (Fringillidae, Carduelinae). Recent studies based on limited genetic evidence instead suggest an isolated position within Passeroidea and advocate a separate family, Urocynchramidae, as had been suggested much earlier on the grounds of morphology. We provide a time-calibrated multi-locus phylogeny for Passeroidea including Przevalski's Finch based on three mitochondrial markers and three nuclear introns that placed U. pylzowi in a clade together with Estrildidae, Viduidae and Ploceidae. A sister group relatio…
Growing up with feces: benefits of allo-coprophagy in families of the European earwig
2016
International audience
On the origin of the recent herpetofauna of Sicily: Comparative phylogeography using homologous mitochondrial and nuclear genes
2016
Abstract In contrast to oceanic, continental islands are expected to show less diversification and endemism and thus phylogeographic signatures of multiple colonization events from adjacent continents due to episodic connections by sea level changes. In order to test this situation for the herpetofauna of Sicily, we here focus on three amphibian and four reptile species-groups and investigate their phylogeographic relationships across the Sicily and Messina straits, where Plio-Pleistocene marine transgressions shortened the distances between (or connected) Sicily, North Africa and/or the Italian (Apennine) Peninsula. Using a multi-species, multi-marker phylogeographic approach (mitochondria…
Bone histology, microanatomy, and growth of the nothosauroid Simosaurus gaillardoti (Sauropterygia) from the Upper Muschelkalk of southern Germany/Ba…
2016
Abstract Simosaurus gaillardoti was a large eosauropterygian (Sauropterygia), a group of diverse diapsid marine reptiles. Its occurrence correlates to transgression phases in the Germanic Basin and a former morphological study hypothesized that Simosaurus was capable of sustained swimming. Microanatomical analysis of five long bones revealed functional differences between the humerus and femur but did not confirm sustained swimming in Simosaurus. It had certain active swimming abilities but – based on microanatomy – it was a less efficient swimmer when compared to contemporaneously living nothosaurs. Simosaurus grew with well-vascularized coarse parallel-fibred bone tissue. Growth marks app…