Search results for "Mating"
showing 10 items of 387 documents
THE EFFECTS OF MATING SYSTEM AND GENETIC VARIABILITY ON SUSCEPTIBILITY TO TREMATODE PARASITES IN A FRESHWATER SNAIL, LYMNAEA STAGNALIS
2004
The amount and distribution of genetic variability in host populations can have significant effects on the outcome of host-parasite interactions. We studied the effect of mating system and genetic variability on susceptibility of Lymnaea stagnalis snails to trematode parasites. Mating system of snails from eight populations differing in the amount of genetic variability was manipulated, and self- and cross-fertilized offspring were exposed to naturally occurring trematode parasites in a controlled lake experiment. Susceptibility of snails varied between populations, but mating-system treatment did not have a significant effect. Heterozygosity of snails was negatively correlated with the pro…
Food Habits of the Javelin Sand Boa Eryx jaculus (Linnaeus 1758; Serpentes, Erycidae) in Sicily, Italy
2021
The Javelin Sand Boa, Eryx jaculus, is reported to be a predator of mammals, lizards and their eggs, and occasionally of birds and invertebrates, but data on its diet are scarce and fragmentary. Here we describe some aspects of the feeding behavior of E. jaculus on the Mediterranean island of Sicily. A total of 132 individual snakes were examined. Prey remains were found in 43% of them, both in their feces (82.5%) and gut contents (17.5%). The number of snakes observed and their feeding rate decreased in August, probably as a result of the relatively higher temperatures. Feeding rate increases were observed in adult females in September, perhaps to enhance body reserves before hibernation. …
Mating (marriage) patterns and economic development
2011
This paper looks at the relationship between economic development and mating (marriage) patterns in the very long run. For this purpose we introduce the Goldin and the Kuznets curves which relate female labour and income inequality with economic development respectively. To some extent, the Goldin and the Kuznets curves have followed opposite paths, which in turn, could illustrate how economic development has had an impact on mating (marriage) patterns, and thus household formation. Convergence in mating patterns among hunter-gatherers across societies vanished after the Neolithic revolution. Then, African polygyny and the ‘European’ marriage pattern developed into the most significant exce…
Feeding habits, post-embryonic and adult survival, mating, virility and fecundity of the predacious miteAmblyseius swirskii [Acarina: Phytoseiidae] o…
1977
The nutritional value forAmblyseius swirskiiAthias-Henriot, of eggs or crawlers ofCoccus hesperidum L.,Saissetia oleae (Olivier),S. coffeae (Walker),Pseudococcus citriculusGreen, andP. longispinusTarg.-Tozz, even with the addition of honeydew, was low; only a few young reached adulthood and the oviposition rate was negligible. However, addition of honeydew toTetranychus cinnabarinusBoisd. enhanced the oviposition rate ofAmblyseius swirskii. Honeydew was a favourite food forA. swirskii, whereas the eggs and crawlers tested were not eagerly attacked and consumed. Females and males fed honeydew ofSaissetia oleae mated readily and the females were inseminated, but fecundity was negligible.
Microhabitat selection and audible sexual signalling in the wolf spider Hygrolycosa rubrofasciata (Araneae, Lycosidae)
2000
We studied the microhabitat selection and male sexual signalling behaviour in the wolf spider Hygrolycosa rubrofasciata (Ohlert). Males strike dry leaves with their abdomen, producing an audible sexual drumming signal, and females use this signal to choose mating partners. In the field we followed male drum- ming rate and microhabitat selection using both the mark-recapture method and direct observations. In the laboratory we conducted an experiment on male micro- habitat and drumming substrate selection. We found that in the field males were not distributed randomly among the habitat; fewer males were found in areas that had high sedge cover, low elevation, and low dry leaf cover. In the l…
Has innate immunity evolved through different routes?
2010
Invertebrate self/non-self recognition, defense responses, mating and development share innate immune surveillance and functions challenged by competition and linked to fitness. Independent evolutionary branches of immune responses may use conserved gene traits. On the other hand immunity genes may be conserved due to their role in development. Finally, upregulation of innate immunity genes during ascidian metamorphosis supports the danger hypothesis.
LES DISCRIMINATIONS A L'EMBAUCHE DANS LA SPHERE PUBLIQUE : EFFETS RESPECTIFS DE L'ADRESSE ET DE L'ORIGINE
2016
Cette étude évalue la discrimination dans l’accès à l’emploi dans trois professions présentes à la fois dans le secteur privé et dans la Fonction Publique. Deux dimensions sont examinées : l’effet de la réputation du lieu de résidence et l’effet de l’origine maghrébine. Elle est réalisée sur données expérimentales de testing réalisé dans trois professions en tension pour lesquelles la discrimination devrait a priori être très réduite : les responsables administratifs de catégorie A, les techniciens de maintenance de catégorie B et les aides soignantes de catégorie C. Pour chaque profession, nous avons construit 3 profils fictifs de candidats à l’emploi similaires en tout point à l’exception…
Mannheimer Innovationspanel (MIP), Scientific-Use-Files der Jahre 1993-2016
2018
Das ZEW erhebt seit 1993 jährlich Daten zum Innovationsverhalten der deutschen Wirtschaft. Die Innovationserhebung deckt die Bereiche Bergbau, verarbeitendes Gewerbe, Energie, Baugewerbe, unternehmensnahe Dienstleistungen und distributive Dienstleistungen ab. Sie ist für Deutschland repräsentativ und ermöglicht Hochrechnung für die deutsche Wirtschaft insgesamt sowie für einzelne Branchengruppen. Es wird im Auftrag des BMBF und in Kooperation mit infas und dem Fraunhofer-ISI durchgeführt. Das MIP ist gleichzeitig der deutsche Beitrag zu den Community Innovation Surveys (CIS) der Europäischen Kommission. Die jährliche Innovationserhebung ist als Panelbefragung konzipiert. Dabei werden jedes …
Mannheimer Innovationspanel (MIP), Scientific-Use-Files der Jahre 1993-2014
2018
Das ZEW erhebt seit 1993 jährlich Daten zum Innovationsverhalten der deutschen Wirtschaft. Die Innovationserhebung deckt die Bereiche Bergbau, verarbeitendes Gewerbe, Energie, Baugewerbe, unternehmensnahe Dienstleistungen und distributive Dienstleistungen ab. Sie ist für Deutschland repräsentativ und ermöglicht Hochrechnung für die deutsche Wirtschaft insgesamt sowie für einzelne Branchengruppen. Es wird im Auftrag des BMBF und in Kooperation mit infas und dem Fraunhofer-ISI durchgeführt. Das MIP ist gleichzeitig der deutsche Beitrag zu den Community Innovation Surveys (CIS) der Europäischen Kommission. Die jährliche Innovationserhebung ist als Panelbefragung konzipiert. Dabei werden jedes …