Search results for "periytyvyys"
showing 6 items of 16 documents
A link between heritable parasite resistance and mate choice in dung beetles
2019
Parasites play a central role in the adaptiveness of sexual reproduction. Sexual selection theory suggests a role for parasite resistance in the context of mate choice, but the evidence is mixed. The parasite-mediated sexual selection (PMSS) hypothesis derives a number of predictions, among which that resistance to parasites is heritable, and that female choice favors parasite resistance genes in males. Here, we tested the PMSS hypothesis using the dung beetle Onthophagus taurus, a species that can be heavily parasitized by Macrocheles merdarius mites, which are known to affect adult survival. We investigated the heritability of resistance to M. merdarius, as well as whether female O. tauru…
Fonologisen rekoodauksen oppiminen kirjain-äänne -vastaavuudeltaan säännöllisessä suomen kielessä
2001
Perhe, työttömyys ja lama
2002
Huono-osaisuus työmarkkinoilla kasautuu perheisiin. Näin ollen voidaan kärjistetysti sanoa perheen olevan joillekin ongelma. Työttömyyden kasautumisen ongelman alkua on vaikea osoittaa, mutta kyse ei ole yksinomaan ympäristötekijöistä kuten paikalliset työmarkkinat. Perhe olennaisena sosialisaation ja identiteetin muotoutumisen viitekehyksenä levittää tavalla tai toisella myös työttömyysriskiä, toteaa Ilkka Virmasalo väitöstutkimuksessaan. Virmasalo tarkasteli tutkimuksessaan kotitalouteen ja perheeseen liittyvien tekijöiden sekä työttömyyden keskinäistä riippuvuutta erilaisissa taloudellisissa olosuhteissa vuosien 1980-1995 välillä.
Endurance in excercise is associated with courtship call rate in decorated cricket, Gryllodes sigillatus
2009
Question: Is sexual signalling (courtship call rate) determined by physiological fitness (energy metabolism at rest), endurance during physically demanding activity, an aspect of immune defence (lytic activity) or body mass? Organism: Pedigree laboratory population of decorated crickets (Gryllodes sigillatus). Methods: Behavioural trial of male courtship call rate and measurements of males’ physiological performance. Covariance analysis exploring the determinants of courtship call rate. Results: We found that endurance was strongly positively associated with the courtship call rate. However, neither the lytic activity nor the resting metabolic rate correlated with courtship call rate. Toget…
Defense against predators incurs high reproductive costs for the aposematic moth Arctia plantaginis
2020
Abstract To understand how variation in warning displays evolves and is maintained, we need to understand not only how perceivers of these traits select color and toxicity but also the sources of the genetic and phenotypic variation exposed to selection by them. We studied these aspects in the wood tiger moth Arctia plantaginis, which has two locally co-occurring male color morphs in Europe: yellow and white. When threatened, both morphs produce defensive secretions from their abdomen and from thoracic glands. Abdominal fluid has shown to be more important against invertebrate predators than avian predators, and the defensive secretion of the yellow morph is more effective against ants. Her…