Hybridization is particularly widespread in birds and can affect species status and recovery. The common quail Coturnix coturnix is a protected game species that has undergone significant population decrease due to habitat changes. The release of Japanese quail C. japonica and or hybrids for restocking has been occurring since the 1970’s. Both species have not developed reproductive isolating mechanisms and hybridization is occurring. Species distinction based on morphology and male callings is difficult. In this work cytochrome b gene and five microsatellite loci were used with the aim of establishing an identification test for quails sampled in Portugal. Cytochrome b gene revealed to be of promising use to identify the quail maternal lineage. Success in species assignment with the studied microsatellite loci was moderate to identify samples with suspicion of being hybrids with common quail maternal lineage.
Monitoring of the analysed populations of the endangered fish species Misgurnus fossilis was conducted using microsatellite analysis and sequencing of a part of the control region. Absolutely first microsatellite markers for weather loach were found. Six polymorphic microsatellite loci were prepared, five of which were tested. Number of alleles per a locus ranged from 3 to 5. All studied populations are differentiated one from another (FST= 0.205 - 0.367). All sampled populations contained unique alleles. Sequential analysis of the mitochondrial control region showed great haplotype similarity of the studied populations which come from one widely spread haplotype H_1, and thus suggested possible hypothesis of recent spreading from one source.
A landscape genetics approach was applied to common goby (Pomatoschistus microps) sampled from three estuaries (six sites) of the Portuguese coast. Individuals of each site were genotyped for eight microsatellite loci and levels of genetic diversity and differentiation were correlated to present-day estuarine characteristics and historical events. A general ecological state for each sampling site was obtained from a principal component analysis (PCA) applied to estuarine geomorphologic characteristics and levels of heavy metals and total polycyclic aromatic hydrocarbons contamination. Genetic diversity was higher than that previously reported for common goby in the Atlantic and Mediterranean. FST were generally very low (0.000-0.049), as well as Nei’s genetic distances (0.000-0.167), although the later were statistically significant. Estuarine geomorphology and heavy metal contamination contributed the most to estuarine ecological differentiation but no trend was detected in the relationship between these characteristics and samples’ genetic diversity. Mantel tests also revealed no significant relationships between geographic, genetic and ecological distances. Null alleles only contributed to explain significant Hardy-Weinberg departures in two of the eight loci scored, although disequilibria were detected in at least two loci per sample. Notwithstanding its exploratory character, results suggest an important role for historical factors in the timing and direction of P. microps colonization of the Portuguese estuaries. Environmental variation and P. microps ability to cope with it are also structuring factors in establishing and maintaining the patchy genetic diversity detected in the studied estuaries.
In this paper I review genetic studies of black grouse to date. The topics cover different areas such as reproductive biology, mating system and, more recently, conservation genetics. The accumulated evidence shows that in the western part of the range of the species, populations are genetically differentiated. Furthermore, small and isolated populations have lost genetic variation due to increased levels of inbreeding and genetic drift. So far the vast majority of studies have been based on microsatellites. More recent investigations have employed sequence data as well as methods to study quantitative trait variation. These latter studies may aid in resolving the issue of whether local populations show any evidence of being adapted to local conditions. This is an important consideration in conservation biology since it determines the extent to which populations are interchangeable and which populations should be used for restocking if such are considered of value.
Crested newts (Triturus cristatus superspecies) are a group of closely related species with parapatric distributions that are likely to interbreed where their ranges meet. Coexistence of three species of the complex (Triturus cristatus, T. dobrogicus and T. carnifex) has been recently confirmed in central Europe. In this study we aim to elucidate the distribution of crested newts in contact zones in the Czech Republic and Slovakia, and determine the extent of hybridization and introgression using nuclear (microsatellites and Randomly Amplified Polymorphic DNA, RAPD) and mitochondrial DNA (mtDNA) markers. Nuclear markers reveal hybrid zones between T. cristatus and T. dobrogicus at the foothills of the Carpathians in southern Slovakia, and between T. cristatus and T. carnifex in the southern parts of the Czech Republic. Analysis of mitochondrial cytochrome b sequences reveals T. cristatus and T. dobrogicus-specific haplotypes in contact zones in southern Slovakia. Surprisingly, most T. carnifex and individuals with mixed ancestry between T. carnifex and T. cristatus possess haplotypes specific for T. dobrogicus, most likely as a result of historical mtDNA introgression. Only one T. carnifex-specific haplotype carried by a single specimen is found in the Czech Republic. Our study shows that genetic structure of central European populations of crested newts is complex and influenced by historical and contemporary hybridization.
Tapinoma melanocephalum is a worldwide distributed, highly invasive ant species. It lives in close association with human societies and its distribution is human-mediated in large measure. The geographical origin of this ant species is unknown, but its introduction in areas previously devoided of its presence can represent a threat to the native biota, act as an agricultural pest or as a pathogen vector. To investigate the genetic structure and phylogeography of this species we identified 12 new polymorphic microsatellite markers, and in addition, we tested and selected 12 ant-universal microsatellites polymorphic in T. melanocephalum. We genotyped 30 individuals from several islands of Micronesia and Papua-New Guinea. All 24 loci exhibited strong homozygosity excess (45-100%, mean = 86%), while the number of alleles per locus reached usual values (2-18, mean = 6.5), resulting in levels of expected heterozygosity much higher than observed. Based on several robust tests, we were able to exclude artefacts such as null alleles and allelic dropout as a possible cause of the observed pattern. Homozygosity excess might be a consequence of founder effect, bottleneck and/or inbreeding. As our sample population was composed of individuals from several distinct localities, the Wahlund effect might have contributed to the increased homozygosity as well. Despite the provisionally observed deviation from the Hardy-Weinberg equilibrium, the newly developed microsatellites will provide an effective tool for future genetic investigations of population structure as well as for the phylogeographic study of T. melanocephalum., Jan Zima Jr., Ophélie Lebrasseur, Michaela Borovanská, Milan Janda., and Obsahuje bibliografii
The Azorean bat (Nyctalus azoreum), the only endemic mammal of the Azores archipelago (Portugal), diverged recently from its mainland relative, the Leisler’s bat (N. leisleri). Although the two species are phenotypically very different, mtDNA studies detected very low genetic divergence between them, which could question the validity of the species status of N. azoreum. In order to assess the genetic variability in each species and check for present levels of gene flow between the two taxa, eight microsatellite loci were genotyped and analysed. The results indicated lower genetic diversity in the insular species. Many unshared alleles were found between the two species and no evidence of migrants, which provides strong support against any contemporary gene flow between them. The species status of the Azorean bat is discussed in the light of the cohesion species concept, and we conclude that it is an isolated species with a high conservation value.