The ecology of small mammal communities found in set-aside and adjacent farm land was investigated to determine the ecological consequences of set-aside land to small mammals. Field work was carried out for two years at three study sites in NE Scotland. First Aldroughty farm, a mosaic of set-aside, crop and semi-natural land. The two remaining study sites; Ythan Lodge at Newburgh, and Fraser's farm near Aldroughty, were whole fields of set-aside. Wood mice <i>Apodemus sylvaticus</i>, bank voles <i>Clethrionomys glareolus</i> and field voles <i>Microtus agrestis</i> were trapped in the habitat mosaic at Aldroughty, and wood mice and field voles in the set-aside at Newburgh. Wood mice had higher densities, greater survival, heavier weights, longer breeding seasons and more juveniles at Aldroughty than Newburgh. These differences were thought to be due to a difference in habitat productivity between the two sites. Field voles showed less of a difference in population dynamics between Aldroughty and Newburgh, and both species of vole maintained populations at low density. The home range size of 33 wood mice was measured using radiotelemetry. At both study sites home range size was smaller than in other habitats revealed by other studies. The apparently anomalous results obtained, of low population densities and small home range sizes of wood mice in the set-aside at Newburgh, may have been due to predation from cats <i>Felis catus</i>. Wood mice showed no clear habitat preference, nesting and foraging in all habitat types, while both vole species showed almost exclusive preference for rough grassland. An assessment of the habitat characteristics of the study sites showed that there was heterogeneity in the vegetation communities found in set-aside.

<p>Sex chromosomes are useful in elucidating the evolutionary factors affecting diversity and divergence. In particular, Y chromosome analyses may complement studies using mitochondrial DNA for inferring sex-specific population genetic processes.</p><p>Y chromosome studies have been scarce due to limited access to genetic markers and the dynamic evolution of Y. Conserved Y-specific primers that could amplify a diverse set of mammalian species were developed from comparison of gametologous X and Y sequences. Y-specific sequence, generally more than one kb, was amplified for all 20 species examined.</p><p>Intraspecific diversity on mammalian Y was found to be reduced even when male-biased mutation rate and effective population size were corrected for. A number of factors can cause this low variation on Y of which selection on a haploid chromosome seems most important.</p><p>The field vole (<i>Microtus agrestis</i>), a common and well-studied small mammal in Eurasia, was examined for X and Y variability. Earlier studies on mtDNA had shown that the field vole is separated in two distinct lineages in Europe. The X and Y chromosome sequences confirmed the deep split and suggested that the two lineages of field vole should be reclassified as two separate species.</p><p>Two distinct Y chromosome haplogroups were found in modern European cattle, distributed among breeds according to a north-south gradient. Ancient DNA analysis of European aurochsen showed the northern haplogroup to be the most common, possibly indicating local hybridization between domestic cows and wild aurochs bulls in Europe.</p>

Sex chromosomes are useful in elucidating the evolutionary factors affecting diversity and divergence. In particular, Y chromosome analyses may complement studies using mitochondrial DNA for inferring sex-specific population genetic processes. Y chromosome studies have been scarce due to limited access to genetic markers and the dynamic evolution of Y. Conserved Y-specific primers that could amplify a diverse set of mammalian species were developed from comparison of gametologous X and Y sequences. Y-specific sequence, generally more than one kb, was amplified for all 20 species examined. Intraspecific diversity on mammalian Y was found to be reduced even when male-biased mutation rate and effective population size were corrected for. A number of factors can cause this low variation on Y of which selection on a haploid chromosome seems most important. The field vole (Microtus agrestis), a common and well-studied small mammal in Eurasia, was examined for X and Y variability. Earlier studies on mtDNA had shown that the field vole is separated in two distinct lineages in Europe. The X and Y chromosome sequences confirmed the deep split and suggested that the two lineages of field vole should be reclassified as two separate species. Two distinct Y chromosome haplogroups were found in modern European cattle, distributed among breeds according to a north-south gradient. Ancient DNA analysis of European aurochsen showed the northern haplogroup to be the most common, possibly indicating local hybridization between domestic cows and wild aurochs bulls in Europe.

The aim of the study was to find out the character of abundance fluctuations in a field vole population on immission clearings in the Krušné (Ore) Mountains during a 25 year series of trapping. Another aim was to find out the influence of climaticconditions on these cycles, concretely the influence of local climatic condition and the influence of North-Atlantic oscillation

Abstract The evaluation of the effects and levels of contaminants in wildlife is an essential part of assessing risks for chemical exposure in the environment. Although the circumstances are not as controlled as in laboratory, wildlife studies offer the concept of environmental exposure in its entirety, with all the natural variation. In the present study, two wild vole species, bank vole (Myodes glareolus) and field vole (Microtus agrestis), were used in assessing environmental levels of dioxins. The effects of dioxin exposure on tooth and bone development were studied in order to determine whether they could be used as biomarkers for environmental exposure. Xenobiotic metabolism activity after dioxin exposure – both natural and experimental – was studied by quantifying selected cytochrome P-450 (CYP) enzymes. The results confirmed the fact that dioxins are ubiquitous in the environment, also in areas far from contaminant sources and human activity. The development of the third molar in bank vole was found to be a sensitive biomarker for dioxin exposure. The two vole species under study do not respond similarly to environmental concentrations of dioxins; there were significant differences in body burdens and activity levels of xenobiotic metabolizing enzymes. / Tiivistelmä Haitallisten kemikaalien tason ja vaikutusten arviointi ympäristössä on olennainen osa kemikaalien riskin arviointia. Vaikka laboratoriossa olosuhteita kontrolloidaan ja tutkimukseen vaikuttava variaatio on paremmin hallittavissa, luonnonvaraisten lajien tutkiminen luo kokonaisvaltaisen ja todenmukaisen kuvan ympäristön kemikaalialtistuksesta kaikkine todellisine vaihteluineen. Tässä väitöskirjassa tarkastellaan kahden luonnonvaraisen pikkunisäkkään, metsämyyrän (Myodes glareolus) ja peltomyyrän (Microtus agrestis), käyttöä ympäristön kemikaalitason arvioinnissa. Pääpaino on dioksiinien kaltaisissa yhdisteissä. Työssä tutkitaan yhdisteiden kertymistä myyriin kahdessa ympäristössä: voimakkaasti dioksiineilla saastuneella maa-alueella sekä kaukana ihmistoiminnasta sijaitsevassa erämaassa. Herkiksi tiedettyjä vasteita – hampaiden ja luiden kehitystä – käytetään dioksiinialtistuksen indikaattoreina. Vierasainemetaboliasta vastaavien entsyymien (sytokromi P450 eli CYP) aktiivisuutta kartoitetaan molemmilla myyrälajeilla, jotta saadaan tietoa entsyymien indusoinnista luonnonvaraisilla myyrillä yleensä ja selvitetään havaittuja lajien välisiä eroja dioksiinivasteissa. Tulokset vahvistavat, että dioksiinit ovat laajalle levinneitä yhdisteitä, joita löytyy paitsi läheltä päästölähdettä myös kaukana ihmistoiminnasta olevilta alueilta. Metsämyyrällä kolmannen poskihampaan kehitys osoittautuu herkäksi dioksiinialtistuksen biomarkkeriksi. Samasta elinympäristöstä huolimatta tutkituista myyrälajeista mitatut dioksiinipitoisuudet eroavat huomattavasti toisistaan, samoin kuin vierasainemetaboliasta vastaavien entsyymien aktiivisuus ja niiden induktio TCDD-altistuksen jälkeen.