Search results for "590"

Sperm competition in yellow dung flies: No consistent effect of sperm size

2022

The male competition for fertilization that results from female multiple mating promotes the evolution of increased sperm numbers and can impact sperm morphology, with theory predicting that longer sperm can at times be advantageous during sperm competition. If so, males with longer sperm should sire more offspring than competitors with shorter sperm. Few studies have directly tested this prediction, and findings are inconsistent. Here we assessed whether longer sperm provide a competitive advantage in the yellow dung fly (Scathophaga stercoraria; Diptera: Scathophagidae). Initially, we let brothers with different temperature-mediated mean sperm lengths compete - thus minimizing confounding…

Yersinia pestis DNA from Skeletal Remains from the 6th Century AD Reveals Insights into Justinianic Plague

2013

Yersinia pestis, the etiologic agent of the disease plague, has been implicated in three historical pandemics. These include the third pandemic of the 19th and 20th centuries, during which plague was spread around the world, and the second pandemic of the 14th–17th centuries, which included the infamous epidemic known as the Black Death. Previous studies have confirmed that Y. pestis caused these two more recent pandemics. However, a highly spirited debate still continues as to whether Y. pestis caused the so-called Justinianic Plague of the 6th–8th centuries AD. By analyzing ancient DNA in two independent ancient DNA laboratories, we confirmed unambiguously the presence of Y. pestis DNA in…

Parent–offspring conflict and the genetic trade-offs shaping parental investment

2015

The genetic conflict between parents and their offspring is a cornerstone of kin selection theory and the gene-centred view of evolution, but whether it actually occurs in natural systems remains an open question. Conflict operates only if parenting is driven by genetic trade-offs between offspring performance and the parent's ability to raise additional offspring, and its expression critically depends on the shape of these trade-offs. Here we investigate the occurrence and nature of genetic conflict in an insect with maternal care, the earwig Forficula auricularia. Specifically, we test for a direct response to experimental selection on female future reproduction and correlated responses i…

Breeding state and season affect interspecific interaction types: indirect resource competition and direct interference.

2011

Indirect resource competition and interference are widely occurring mechanisms of interspecific interactions. We have studied the seasonal expression of these two interaction types within a two-species, boreal small mammal system. Seasons differ by resource availability, individual breeding state and intraspecific social system. Live-trapping methods were used to monitor space use and reproduction in 14 experimental populations of bank voles Myodes glareolus in large outdoor enclosures with and without a dominant competitor, the field vole Microtus agrestis. We further compared vole behaviour using staged dyadic encounters in neutral arenas in both seasons. Survival of the non-breeding over…

Contrasting parental roles shape sex differences in poison frog space use but not navigational performance

2022

Sex differences in vertebrate spatial abilities are typically interpreted under the adaptive specialization hypothesis, which posits that male reproductive success is linked to larger home ranges and better navigational skills. The androgen spillover hypothesis counters that enhanced male spatial performance may be a byproduct of higher androgen levels. Animal groups that include species where females are expected to outperform males based on life-history traits are key for disentangling these hypotheses. We investigated the association between sex differences in reproductive strategies, spatial behavior, and androgen levels in three species of poison frogs. We tracked individuals in natura…

García Hurtado, Manuel Reyes (ed.): Soltando amarras: La costa noratlántica ibérica en la Edad Moderna

2021

Lobo Cabrera, Manuel: Doña Juana de Austria. La princesa gobernadora

2021

Desafíos del sindicalismo italiano ante el trabajo sindical con trabajadores ?contingentes? en Amazon

2021

Marine data collection and transmission system for ECO-boat

2014

Masteroppgave i Informasjons- og kommunikasjonsteknologi IKT590 Universitetet i Agder 2014 Marine data collection is of great importance because the analytical results based onthe collected data can be utilized for many purposes during the design phase beforesale as well as the maintenance phase of the boat after sale. In this thesis, I havedesigned and implemented a marine data collection and transmission system foryachts. The system can collect data from an NMEA network, a wireless sensornetwork, a custom-made CAN-bus network, and other sensors such as a 9degree-of-freedom inertial measurement units. The collected data is stored both atthe boat and at a remote server. In this design, I us…

Organización del trabajo y culturas laborales en los feminizados almacenes de la globalización agroalimentaria

2021

La globalización del sistema agroalimentario ha transformado la organización del trabajo en los campos y almacenes agrícolas. El almacén de manipulado y confección de frutas y hortalizas constituye un lugar clave para analizar las estrategias de acumulación de la agroindustria y sus efectos sobre la organización social del trabajo, en particular, la relación entre estas estrategias y los procesos de feminización y desvalorización del trabajo agrícola. Una desvalorización del trabajo femenino que es un elemento clave en la competitividad del sector agrícola y se apoya –y legitima– en una cultura del trabajo determinada. Este artículo examina la forma que adquiere esta relación y sus implicac…