Search results for "valinta"
showing 10 items of 249 documents
Effects of soil metal contamination on genetic diversity of the earthworm Dendrobaena octaedra (Savigny) in three metal contaminated areas in Finland
2007
Evolutionary conflicts in a small mammal : behavioural, physiological and genetic differences between the sexes
2011
Competition for space as a mechanism for density- and frequency-dependent selection on bank vole (Myodes glareolus) females
2008
Condition-dependence of male sexual signalling in the drumming wolf spider Hygrolycosa rubrofasciata
2003
Jari Ahtiaisen väitöskirjatyön tutkimusten perusteella voidaan todeta, että H. rubrofasciata susihämähäkkinaaraat voivat käyttää koiraan seksuaalista kuntoa mittana arvioidessaan koiraan fenotyyppistä ja geneettistä laatua. Näyttäisi myös siltä, että seksuaalivalinnalla on merkittäviä populaatiotason vaikutuksia. Eläinten seksuaaliominaisuudet voivatkin tulevaisuudessa tarjota uusia keinoja populaatioiden sukupuuttouhan ja elinkyvyn arvioimiseen. The ´good genes´ or ´handicap´ model of sexual selection focuses on the evolution of female preferences for male sexual traits by using condition-dependence as the mediating mechanism. As the ´size´ of the preferred sexual trait increases, male fit…
Developments in the evolutionary theory of social interactions
2016
Altruistic behaviour, which benefits others but harms the actor, can evolve when copies of the underlying genes are transmitted to future generations by related beneficiaries. While we know that the mechanism of ‘kin selection’ answers to how altruism can evolve, the answers to why and when it can evolve are still obscure. The first aim of this thesis is to shed light to the evolution of altruism by identifying factors that facilitate or promote it. I find that the conditions under which altruism can evolve follow surprisingly simple principles that are independent of the taxon-specific traits such as fecundity. Further, by analysing the unique aspects of haplodiploid sex determination syst…
Tutkiva oppiminen evoluution opetuksessa lukiossa
2017
Uusi opetussuunnitelma velvoittaa opettajia kokeellisuuden ja tutkimuksellisuuden hyödyntämiseen opetuksessa, ja eräs keino tähän on tutkiva oppiminen. Tutkivassa oppimisessa tietoa ei omaksuta suoraan oppikirjasta tai opettajalta, vaan sitä hankitaan tieteelle tuttujen toimintamallien, kuten kysymysten, hypoteesien, selitysten ja kokeiden avulla. Tutkivan oppimisen vaiheet muodostavat yhdessä tutkivan oppimisen polun, jossa tieto tarkentuu vaihe vaiheelta. Opiskelijoita voidaan haastaa tutkivassa oppimisessa eri tavalla riippuen ovatko tutkimuskysymykset, menetelmät tai ratkaisut annettu heille etukäteen. Tutkivaa oppimista voidaan hyödyntää erilaisten aihepiirien opetuksessa kaikenikäiste…
Introgression of mitochondrial DNA among Myodes voles: consequences for energetics?
2011
Background Introgression of mitochondrial DNA (mtDNA) is among the most frequently described cases of reticulate evolution. The tendency of mtDNA to cross interspecific barriers is somewhat counter-intuitive considering the key function of enzymes that it encodes in the oxidative-phosphorylation process, which could give rise to hybrid dysfunction. How mtDNA reticulation affects the evolution of metabolic functions is, however, uncertain. Here we investigated how morpho-physiological traits vary in natural populations of a common rodent (the bank vole, Myodes glareolus) and whether this variation could be associated with mtDNA introgression. First, we confirmed that M. glareolus harbour mtD…
Darwin and Ethics : Using Natural Selection to Understand Ethical Business and Organizational Behavior
2000
The origins of ethics and morality have been considered for many, many years. From ancient Greek metaphysicians to the great theologians of the Middle Ages to modern philosophers, different systematic frameworks have been developed to understand how and why ethics are formed. These frameworks provide people and organizations with guidance about how to act toward other humans and institutions in their environment. Steiner and Steiner (1991) discuss six different primary sources for understanding the development of ethics: religious, philosophical, cultural, legal, codes of conduct, and genetics (see Table). Of these six systems, the genetic framework is clearly the least developed, least exp…
Experimental evolution of evolutionary potential in fluctuating environments
2023
Variation is the raw material for evolution. Evolutionary potential is determined by the amount of genetic variation, but evolution can also alter the visibility of genetic variation to natural selection. Fluctuating environments are suggested to maintain genetic variation but they can also affect environmental variance, and thus, the visibility of genetic variation to natural selection. However, experimental studies testing these ideas are relatively scarce. In order to determine differences in evolutionary potential we quantified variance attributable to population, genotype and environment for populations of the bacterium Serratia marcescens. These populations had been experimentally evo…