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Moor Frog (moor + frog)
Selected AbstractsGEOGRAPHIC VARIATION IN ACID STRESS TOLERANCE OF THE MOOR FROG, RANA ARVALIS.EVOLUTION, Issue 2 2003Abstract Spatially varying directional selection together with restricted gene flow among populations is expected to lead to local adaptation. One environmental factor that potentially causes strong directional selection, but is little explored in evolutionary terms, is naturally and anthropogenically induced acidity. We studied local adaptation to acidity in four Swedish populations (two originating from areas that have suffered from severe anthropogenic acidification during the 1900s and two from areas which have remained neutral due to higher buffering capacity) of the moor frog Rana arvalis in a laboratory experiment by investigating whether differences in acid tolerance correspond to population origin. Embryos were raised from fertilization to hatching at three different pH levels (pH 4.0, 4.25 and 7.5), corresponding to levels experienced by these populations in nature, and acid stress tolerance was measured in terms of embryonic survival, hatchling size, and age. Evidence for local adaptation in all of these traits was found, the acid origin embryos having higher survival and less impaired growth performance under acid conditions than the neutral origin embryos. Our estimated rates of divergence (0.007,0.102 haldanes) suggest a rapid adaptation process in response to anthropogenic environmental change, and that the different traits have evolved at relatively similar rates. [source] Effects of ultraviolet-B radiation and pH on early development of the moor frog Rana arvalisJOURNAL OF APPLIED ECOLOGY, Issue 3 2001Maarit Pahkala Summary 1,Although the potential negative effects of increased ultraviolet-B (UV-B) radiation on early life stages of aquatic organisms are widely recognized, possible synergistic effects with other stressors have seldom been studied outside the laboratory. We investigated the effects of UV-B radiation and pH on hatchability and early development of moor frog Rana arvalis eggs in the field and in laboratory experiments conducted during April 1998 and April 2000 in central Sweden. 2,In the field experiments, no evidence was found for reduced hatchability or increased frequency of developmental anomalies of embryos exposed to ambient levels of UV-B compared with embryos shielded from UV-B radiation. 3,Hatchlings shielded from ambient UV-B radiation did not grow larger than their exposed full-sibs, giving no support to the hypotheses that (i) the repair of cellular UV-B damage might be energetically costly nor (ii) that UV-B-induced photoproducts directly reduce growth. 4,Although low pH (5·0) reduced hatchability, increased frequency of developmental anomalies and reduced early embryonic growth in R. arvalis, there was no evidence for synergistic effects of pH and UV-B on any of these traits. 5,The lack of UV-B radiation effects on the development of R. arvalis embryos cannot be ascribed to relatively low effective daily doses of radiation (c. 0·43 kJ m,2) during the field experiments, as in the laboratory even higher doses at UV-B 1·25 kJ m,2 and 1·58 kJ m,2 (all DNA weighed) had no negative effects. 6,These results suggest that current levels of UV-B radiation in northern Europe are not likely to reduce fitness in natural populations of the moor frog, even in areas already stressed by acidity. [source] Mitochondrial phylogeography of the moor frog, Rana arvalisMOLECULAR ECOLOGY, Issue 6 2004W. Babik Abstract The moor frog Rana arvalis is a lowland species with a broad Eurasiatic distribution, from arctic tundra through forest to the steppe zone. Its present-day range suggests that glacial refugia of this frog were located outside southern European peninsulas. We studied the species-wide phylogeographical pattern using sequence variation in a 682 base pairs fragment of mtDNA cytochrome b gene; 223 individuals from 73 localities were analysed. Two main clades, A and B, differing by c. 3.6% sequence divergence were detected. The A clade is further subdivided into two subclades, AI and AII differing by 1.0%. All three lineages are present in the Carpathian Basin (CB), whereas the rest of the species range, including huge expanses of Eurasian lowlands, are inhabited solely by the AI lineage. We infer that AII and B lineages survived several glacial cycles in the CB but did not expand, at least in the present interglacial, to the north. The geographical distribution and genealogical relationships between haplotypes from the AI lineage indicate that this group had two glacial refugia, one located in the eastern part of the CB and the other probably in southern Russia. Populations from both refugia contributed to the colonization of the western part of the range, whereas the eastern part was colonized from the eastern refugium only. The effective population size as evidenced by ,ML is an order of magnitude higher in the AI lineage than in the AII and B lineages. Demographic expansion was detected in all three lineages. [source] | ||||||||||