uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
The influence of landscape structure on occurrence, abundance and genetic diversity of the common frog, Rana temporaria
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Population Biology.
(English)In: Journal of Molecular EcologyArticle in journal (Refereed) Submitted
URN: urn:nbn:se:uu:diva-92244OAI: oai:DiVA.org:uu-92244DiVA: diva2:165249
Available from: 2004-10-22 Created: 2004-10-22 Last updated: 2009-03-31Bibliographically approved
In thesis
1. Effects of Agriculture on Abundance, Genetic Diversity and Fitness in the Common Frog, Rana temporaria
Open this publication in new window or tab >>Effects of Agriculture on Abundance, Genetic Diversity and Fitness in the Common Frog, Rana temporaria
2004 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The aims of this thesis were to evaluate the effects of agriculture on amphibians in terms of (i) population genetic consequences of agriculture-induced spatial changes of the landscape and (ii) local adaptation and tolerance to frequently used agrochemicals. The study was performed using the common frog Rana temporaria as a model.

Abundance, occurrence, genetic diversity and gene flow were negatively affected by agriculture in southern Sweden, but unaffected or even positively affected by agriculture in the central and northern regions, respectively. These test parameters correlated positively with landscape diversity both in the south and in the north. Moreover, the size and occurrence of R. temporaria populations decreased towards the north i.e. the margin of the species’ distribution range. In accordance with theoretical expectations, genetic variability decreased and population substructuring increased as a negative function of (effective) population size.

Southern Swedish common frogs are naturally exposed to higher levels of nitrates, and thus have a higher tolerance to high nitrate levels than their northern conspecifics. This suggests local adaptation to naturally varying nitrate levels. Consequently, increased anthropogenic supplementation of nitrate could impact more the northern than the southern Swedish common frog populations. Exposure to the pesticides azoxystrobin, cyanazine and permethrin at ecologically relevant concentrations had small or no effects on R. temporaria tadpoles.

The populations with lowest microsatellite variation (fragmented populations) in southern Sweden had considerably lower fitness in terms of survival and growth as compared to those with the highest genetic variability (non-fragmented populations). The results indicate that populations with low levels of neutral genetic variability were phenotypically less differentiated than populations with higher levels of variability. One possible explanation for this is that the degree of population differentiation in low variability populations has been constrained due to lack of suitable genetic variation or inefficiency of selection relative to genetic drift.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2004. 43 p.
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-232X ; 1025
Biology, agriculture, agrochemicals, amphibians, effective population size, genetic diversity, genetic structure, hierarchical sampling, microsatellites, Rana temporaria, Biologi
National Category
Biological Sciences
urn:nbn:se:uu:diva-4619 (URN)91-554-6060-7 (ISBN)
Public defence
2004-11-12, Zootissalen, Zoologen, Villavägen 9, Evolutionary Biology Centre, Uppsala, 14:15 (English)
Available from: 2004-10-22 Created: 2004-10-22 Last updated: 2009-03-31Bibliographically approved

Open Access in DiVA

No full text

By organisation
Population Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 161 hits
ReferencesLink to record
Permanent link

Direct link