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Within the genus Centaurea L., polyploidy is very common, and it is believed that, as to all angiosperms, it was key in the history of its diversification and evolution. Centaurea tentudaica is a hexaploid from subsect. Chamaecyanus of unknown origin. In this study, we examined the possible autopolyploid or allopolyploid origin using allozymes and sequences of three molecular markers: nuclear-ribosomic region ETS, and low-copy genes AGT1 and PgiC. We also included three species geographically and morphologically close to C. tentudaica: C. amblensis, C. galianoi, and C. ornata. Neighbor-Net and Bayesian analyses show a close relationship between C. amblensis and C. tentudaica and no relationship to any of the other species, which suggest that C. tentudaica is an autopolyploid of C. amblensis. Allozyme banding pattern also supports the autopolyploidy hypothesis and shows high levels of genetic diversity in the polyploid, which could suggest multiple origins by recurrent crosses of tetraploid and diploid cytotypes of C. amblensis. Environmental niche modeling was used to analyze the distribution of the possible parental species during the present, Last Glacial Maximum (LGM), Last Interglacial Period (LIG), and Penultimate Glacial Maximum (PGM) environmental conditions. Supporting the molecular suggestions that C. tentudaica originated from C. amblensis, environmental niche modeling confirms that past distribution of C. amblensis overlapped with the distribution of C. tentudaica.

In order to clarify the genetic differentiation and reproductive traits of mixed polyploid populations in Parasenecio kamtschaticus complex, geographical distribution, genetic diversity, and reproductive performance were compared among three intraspecific types composed of two cytotypes and two varieties in Japan. Diploid P. kamtschaticus var. kamtschaticus (2x-kamtschaticus) was distributed at the center of the distribution range, tetraploid P. kamtschaticus var. kamtschaticus (4x-kamtschaticus) existed widely throughout the entire range, and tetraploid P. kamtschaticus var. bulbifera (4x-bulbifera), producing bulbils, was restricted to higher elevations. Genetic structure was analyzed using allozyme markers. The genetic diversity of 4x-kamtschaticus was higher than that of 2x-kamtschaticus, with that of 4x-bulbifera being intermediate. Populations of 4x-bulbiferaand 2x-kamtschaticus were genetically discriminable from each other in principle coordinate analysis, and the genetic structure of 4x-kamtschaticus populations largely overlapped with those of the other types. Flower and achene production levels were highest in the 4x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Germination activity of achenes was highest in the 2x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Fruit-set success of 4x-bulbifera decreased with elevation because of a shorter growing season, indicating the importance of vegetative reproduction by bulbils at higher elevations. Unexpectedly, the inbreeding coefficients of the 4x-bulbifera populations were the lowest among the three types. Occasional achene production by outcrossing might maintain the high genetic diversity of the 4x-bulbifera populations. The evolution of polyploidy and subsequent bulbil production might enable P. kamtschaticus to disperse a wider range of environmental conditions.

In order to clarify the genetic differentiation and reproductive traits of mixed polyploid populations in Parasenecio kamtschaticus complex, geographical distribution, genetic diversity, and reproductive performance were compared among three intraspecific types composed of two cytotypes and two varieties in Japan. Diploid P. kamtschaticus var. kamtschaticus (2x-kamtschaticus) was distributed at the center of the distribution range, tetraploid P. kamtschaticus var. kamtschaticus (4x-kamtschaticus) existed widely throughout the entire range, and tetraploid P. kamtschaticus var. bulbifera (4x-bulbifera), producing bulbils, was restricted to higher elevations. Genetic structure was analyzed using allozyme markers. The genetic diversity of 4x-kamtschaticus was higher than that of 2x-kamtschaticus, with that of 4x-bulbifera being intermediate. Populations of 4x-bulbiferaand 2x-kamtschaticus were genetically discriminable from each other in principle coordinate analysis, and the genetic structure of 4x-kamtschaticus populations largely overlapped with those of the other types. Flower and achene production levels were highest in the 4x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Germination activity of achenes was highest in the 2x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Fruit-set success of 4x-bulbifera decreased with elevation because of a shorter growing season, indicating the importance of vegetative reproduction by bulbils at higher elevations. Unexpectedly, the inbreeding coefficients of the 4x-bulbifera populations were the lowest among the three types. Occasional achene production by outcrossing might maintain the high genetic diversity of the 4x-bulbifera populations. The evolution of polyploidy and subsequent bulbil production might enable P. kamtschaticus to disperse a wider range of environmental conditions.

In order to clarify the genetic differentiation and reproductive traits of mixed polyploid populations in Parasenecio kamtschaticus complex, geographical distribution, genetic diversity, and reproductive performance were compared among three intraspecific types composed of two cytotypes and two varieties in Japan. Diploid P. kamtschaticus var. kamtschaticus (2x-kamtschaticus) was distributed at the center of the distribution range, tetraploid P. kamtschaticus var. kamtschaticus (4x-kamtschaticus) existed widely throughout the entire range, and tetraploid P. kamtschaticus var. bulbifera (4x-bulbifera), producing bulbils, was restricted to higher elevations. Genetic structure was analyzed using allozyme markers. The genetic diversity of 4x-kamtschaticus was higher than that of 2x-kamtschaticus, with that of 4x-bulbifera being intermediate. Populations of 4x-bulbiferaand 2x-kamtschaticus were genetically discriminable from each other in principle coordinate analysis, and the genetic structure of 4x-kamtschaticus populations largely overlapped with those of the other types. Flower and achene production levels were highest in the 4x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Germination activity of achenes was highest in the 2x-kamtschaticus populations and lowest in the 4x-bulbifera populations. Fruit-set success of 4x-bulbifera decreased with elevation because of a shorter growing season, indicating the importance of vegetative reproduction by bulbils at higher elevations. Unexpectedly, the inbreeding coefficients of the 4x-bulbifera populations were the lowest among the three types. Occasional achene production by outcrossing might maintain the high genetic diversity of the 4x-bulbifera populations. The evolution of polyploidy and subsequent bulbil production might enable P. kamtschaticus to disperse a wider range of environmental conditions.

U radu je izvršen integrativno-taksonomski pristup analize kompleksa vrsta Merodon avidus (Diptera: Syrphidae), na geografski i vemenski obimnom materijalu. U okviru genetičke karakterizacije kriptičnih vrsta navedenog kompleksa, bazirane na 3' i 5' fragmentima mitohondrijalnog COI gena, određeni su parametri genetičke varijabilnosti i utvrđeni jedinstveni i deljeni haplotipovi u okviru i između pretpostavljenih vrsta. Rezultati genetičke varijabilnosti COI DNK sekvenci pokazali su da jedinke sa ostrva Krf i Evia i poluostrva Peloponez, preliminarno identifikovane kao M. moenium, predstavljaju novu, endemsku vrstu proučavanog kompleksa. Dijagnostički enzimski lokusi pokazali su da M. avidus i M. moenium predstavljaju sestrinske vrste, koje su se, u okviru kompleksa vrsta M. avidus, poslednje razdvojile. Zaključeno je da se kompleks vrsta M. avidus sastoji od 5 vrsta: M. avidus, M. moenium, M. megavidus, M. ibericus i M. aff. moenium. U nastavku, oslanjajući se na moderne tehnike veštačke inteligencije, izvršeno je modelovanje distribucije vrsta i poređenje sličnosti utvrđenih ekoloških niša. U poslednjem segmentu istraživanja, prednosti veštačke inteligencije iskorišćene su u modelovanju sistema za determinaciju jedinki sestrinskih vrsta u uzorku, na osnovu adekvatne varijable.Ovo istraživanje doprinelo je karakterizaciji biodiverziteta osolikih muva, rasvetljavanju taksonomskog statusa vrsta i kreiranju smernica za definisanje budućih konzervacionih programa zaštite biodiverziteta vrsta Merodon avidus kompleksa., During this research, an integrative-taxonomic analysis of M. avidus species complex was performed. The study was based on geographically and temporally extensive material. Genetic characterisation of cryptic species, based on 5’ and 3’ regions of COI gene, defined parameters of genetic variability. Shared and unique haplotypes between and within of cryptic species were detected. The results of genetic variability analysis based on COI gene showed that specimens from the islands Corfu, Evia and half-island Peloponnese, which were preliminarily identified as M. moenium, represent a new, endemic species of the selected complex. Diagnostic enzyme loci showed that M. avidus and M. moenium represent sibling species, which were the last one who separated within M. avidus complex. According to current information, it was concluded that M. avidus complex consists of 5 species: M. avidus, M. moenium, M. megavidus, M. ibericus and M. aff. moenium. In the next chapter, relying on modern techniques of artificial intelligence, the species distribution modelling and the comparison of ecological niches were performed. In the last part of the research, the advantages of artificial intelligence were used in order to model a system that was able to determinate one of two sibling species, based on appropriate predictor. This research has generally contributed to a characterization of hoverfly diversity and helped resolving a taxonomic status of species in one of the most challenging groups in Syrphidae family. Genetic differentiation data represent directions for defining future conservation strategies for biodiversity protection of defined cryptic species of Merodon avidus complex

The taxonomic rank of the tiny-leaved terrestrial orchid Cephalanthera subaphylla Miyabe & Kudô has been somewhat controversial, as it has been treated as a species or as an infraspecific taxon, under C. erecta (Thunb.) Blume [C. erecta var. subaphylla (Miyabe & Kudô) Ohwi and C. erecta f. subaphylla (Miyabe & Kudô) M. Hiro]. Allozyme markers, traditionally employed for delimiting species boundaries, are used here to gain information for determining the taxonomic status of C. subaphylla. To do this, we sampled three populations of five taxa (a total of 15 populations) of Cephalanthera native to the Korean Peninsula [C. erecta, C. falcata (Thunb.) Blume, C. longibracteata Blume, C. longifolia (L.) Fritsch, and C. subaphylla]. Among 20 putative loci resolved, three were monomorphic (Dia-2, Pgi-1, and Tpi-1) across the five species. Apart from C. longibracteata, there was no allozyme variation within the remaining four species. Of the 51 alleles harbored by these 17 polymorphic loci, each of the 27 alleles at 14 loci was unique to a single species. Accordingly, we found low average values of Nei’s genetic identities (I) between ten species pairs (from I = 0.250 for C. erecta versus C. longifolia to I = 0.603 for C. falcata vs. C. longibracteata), with C. subaphylla being genetically clearly differentiated from the other species (from I = 0.349 for C. subaphylla vs. C. longifolia to 0.400 for C. subaphylla vs. C. falcata). These results clearly indicate that C. subaphylla is not genetically related to any of the other taxa of Cephalanthera that are native to the Korean Peninsula, including C. erecta. In a principal coordinate analysis (PCoA), C. subaphylla was positioned distant not only from C. falcata, C. longibracteata, and C. longifolia, but also from C. erecta. Finally, K = 5 was the best clustering scheme using a Bayesian approach, with five clusters precisely corresponding to the five taxa. Thus, our allozyme results strongly suggest that C. subaphylla merits the

Protection and management of closely related endangered species and subspecies at a very narrow regional scale is the origin of multiple dysfunctional conservation decisions. These include artificially increased IUCN risk assessment categories and derived consequences: poor effectiveness in allocating public and private funds or repeat of unnecessary actions/facilities. Data provided by the revisited study of a group of W Mediterranean larkspurs (Delphinium ser. Fissa), including new data on demography, niche modeling, genetic diversity and phylogeography, contributed to a new and wider analysis of causes of threat. Although current IUCN Red List regulations did not allow for assessments at levels higher than a specific rank, scientific information suggests that in some cases this could be a better approach for sound scientifically-based biodiversity conservation planning and action.

U radu je izvršen integrativno-taksonomski pristup analize kompleksa vrsta Merodon avidus (Diptera: Syrphidae), na geografski i vemenski obimnom materijalu. U okviru genetičke karakterizacije kriptičnih vrsta navedenog kompleksa, bazirane na 3' i 5' fragmentima mitohondrijalnog COI gena, određeni su parametri genetičke varijabilnosti i utvrđeni jedinstveni i deljeni haplotipovi u okviru i između pretpostavljenih vrsta. Rezultati genetičke varijabilnosti COI DNK sekvenci pokazali su da jedinke sa ostrva Krf i Evia i poluostrva Peloponez, preliminarno identifikovane kao M. moenium, predstavljaju novu, endemsku vrstu proučavanog kompleksa. Dijagnostički enzimski lokusi pokazali su da M. avidus i M. moenium predstavljaju sestrinske vrste, koje su se, u okviru kompleksa vrsta M. avidus, poslednje razdvojile. Zaključeno je da se kompleks vrsta M. avidus sastoji od 5 vrsta: M. avidus, M. moenium, M. megavidus, M. ibericus i M. aff. moenium. U nastavku, oslanjajući se na moderne tehnike veštačke inteligencije, izvršeno je modelovanje distribucije vrsta i poređenje sličnosti utvrđenih ekoloških niša. U poslednjem segmentu istraživanja, prednosti veštačke inteligencije iskorišćene su u modelovanju sistema za determinaciju jedinki sestrinskih vrsta u uzorku, na osnovu adekvatne varijable.Ovo istraživanje doprinelo je karakterizaciji biodiverziteta osolikih muva, rasvetljavanju taksonomskog statusa vrsta i kreiranju smernica za definisanje budućih konzervacionih programa zaštite biodiverziteta vrsta Merodon avidus kompleksa., During this research, an integrative-taxonomic analysis of M. avidus species complex was performed. The study was based on geographically and temporally extensive material. Genetic characterisation of cryptic species, based on 5’ and 3’ regions of COI gene, defined parameters of genetic variability. Shared and unique haplotypes between and within of cryptic species were detected. The results of genetic variability analysis based on COI gene showed that specimens from the islands Corfu, Evia and half-island Peloponnese, which were preliminarily identified as M. moenium, represent a new, endemic species of the selected complex. Diagnostic enzyme loci showed that M. avidus and M. moenium represent sibling species, which were the last one who separated within M. avidus complex. According to current information, it was concluded that M. avidus complex consists of 5 species: M. avidus, M. moenium, M. megavidus, M. ibericus and M. aff. moenium. In the next chapter, relying on modern techniques of artificial intelligence, the species distribution modelling and the comparison of ecological niches were performed. In the last part of the research, the advantages of artificial intelligence were used in order to model a system that was able to determinate one of two sibling species, based on appropriate predictor. This research has generally contributed to a characterization of hoverfly diversity and helped resolving a taxonomic status of species in one of the most challenging groups in Syrphidae family. Genetic differentiation data represent directions for defining future conservation strategies for biodiversity protection of defined cryptic species of Merodon avidus complex

Neutral genetic diversity found in plant species usually leaves an indelible footprint of historical events. Korea’s main mountain range (referred to as the Baekdudaegan [BDDG]), is known to have served as a glacial refugium primarily for the boreal and temperate flora of northeastern Asia. In addition, life-history traits (life forms, geographic range, and breeding systems) influence the within- and among-population genetic diversity of seed plant species. For example, selfing species harbor significantly less within-population genetic variation than that of predominantly outcrossers. A previous study of two Liparis species (L. makinoana and L. kumokiri) emphasizes the role of the abovementioned factors shaping the levels of genetic diversity. Liparis makinoana, mainly occurring on the BDDG and self-incompatible, harbors high levels of within-population genetic diversity (expected heterozygosity, HeP = 0.319), whereas there is no allozyme variation (HeP = 0.000) in L. kumokiri, which is self-compatible and mainly occurs in lowland hilly areas. To determine if this trend is also found in other congeners, we sampled five populations of L. krameri from the southern part of the Korean Peninsula and investigated the allozyme-based genetic diversity at 15 putative loci. The somewhat intermediate levels of within-population genetic variation (HeP = 0.145) found in L. krameri are most likely due to its occurrence in mountainous areas that, despite being outside of the main ridge of the BDDG, still served as refugia, and a self-incompatible breeding system. Management strategies are suggested for L. krameri and L. makinoana based on the levels and distribution of genetic diversity and inbreeding.

The majority of herbivorous insects are specialized in host use. Even among insects that use many hosts, local specialization is common with a single host plant often being used in any given locality. Here, we establish such a pattern for the European swallowtail butterfly, Papilio machaon. We sampled larvae on five different natural hosts at eight sites in Sweden, each locality showing local monophagy. We ask what is the underlying reason for this pattern, (1) local genetic adaptation with each population being genetically adapted to the local host, (2) Hopkins' host selection principle with adult females retaining a memory of the larval host and preferring to oviposit on that plant, or (3) the preference/performance hypothesis which posits that females should oviposit on the local plant(s) on which larval fitness is highest. Allozyme analysis supported a relatively low level of population structuring, and oviposition preference tests showed that females from all sites had similar preference rankings of the five host plants. Hence, there was no support for local genetic adaptation or Hopkins' host selection principle. Instead, the results are consistent with the preference/performance hypothesis with local monophagy probably being implemented by a preference ranking of plants in accordance with larval performance.

Previous studies have shown that levels of genetic diversity in species of the genus Cephalanthera covary with the breeding system. In the southern part of the Korean Peninsula, the three self‐compatible terrestrial orchids Cephalanthera erecta, C. falcata and C. longibracteata flower synchronously in sympatric populations. The food‐deceptive C. falcata with bright yellow flowers is predominantly outcrossing, whereas autogamy is the dominant strategy in both C. erecta and C. longibracteata, whose white flowers do not open fully. We examined genetic diversity (by means of allozymes) of the three species in sympatric populations (600 × 600 m area) in the Yeonwhasan Provincial Park (YPP) and in non‐sympatric populations outside YPP, South Korea. Thirteen out of 20 putative loci were variable across the three species, but there was a complete lack of allozyme variation within each species and we found no evidence of hybridisation. Our results suggest that historical factors, i.e. the Quaternary climate oscillations, have played a major role in determining levels of genetic diversity in the three Cephalanthera species. The Korean populations of C. erecta (a warm‐temperate/temperate element) and C. falcata (a warm‐temperate element) may have been established by a single introduction from a genetically depauperate ancestral population, likely located outside the Korean Peninsula. On the other hand, since C. longibracteata is a boreal/temperate element, it may have survived the Last Glacial Maximum in microrefugia located in low elevation regions within the Peninsula where it has been subjected to population bottlenecks reducing its genetic diversity.

To provide basic information for orchid conservation, we surveyed the plant allozyme literature to summarize genetic diversity and structure data for (i) rare orchids native to the Korean Peninsula, and (ii) their congeners irrespective of being common and rare or Korean or not. A total of 68 taxa (32 taxa in Korea and 37 outside Korea; Goodyera repens being included in both datasets) were considered in this study. Overall, rare Korean orchid species had significantly lower levels of genetic diversity than their common congeners and common orchids in general at both population and species levels. However, mean values of GST (or FST) for rare and common orchids (Korean or not) did not differ significantly from each other. We found patterns of both low and high genetic diversity in rare Korean orchids. Many rare orchids harbored a complete lack of allozyme variation or extremely low within-population variation, perhaps due to rarity associated with random genetic drift and/or, for the case of warm-temperate orchids, to founder effects during post-glacial re-colonization. In contrast, high levels of genetic variation were found for a few orchids that have become recently rare (due to over-collection during the past several decades), probably because there have not been sufficient generations for the initial diversity to be substantially eroded. In addition, several orchids occurring in the main mountain system of the Korean Peninsula (the Baekdudaegan), that served as a glacial refugium, maintained moderate to high levels of within-population genetic diversity. Based on our genetic data, conservation priority should be given to rare orchid species. Particularly, urgent measures should be implemented on Jeju Island, a popular vacation spot, because it also a hotspot for threatened orchids with low levels of genetic diversity.

1.Genetic and ecological data onthe two Antarctic sibling species, C. osculatum sp. D and C. osculatum sp. E (Nematoda: Anisakidae) from fish of the Ross Sea, over a temporal scale ABSTRACT The Ross Sea, Eastern Antarctica, is considered a "pristine ecosystem" and a biodiversity "hotspot". This provides a chance to investigate a marine ecosystem scarcely impacted by human. The sibling species Contracaecum osculatum sp. D and C. osculatum sp. E are parasites embedded in the natural Antarctic marine ecosystem, where they have been documented in sympatry both in their definitive host (Weddell seal) and in fish intermediate/paratenic hosts. Aims of this study were to: 1) identify the larvae of C. osculatum (s.l.) recovered in fish hosts, collected during XXVII Italian Expedition to Antarctica (2011-2012); 2) perform a comparative analysis of the contemporary parasitic load and genetic variability estimates of C. osculatum sp. D and C. osculatum sp. E with respect to past samples collected during expedition 1993-1994. In this aim, a total of 200 fish specimens belonging to four Antarctic species (Chionodraco hamatus, Trematomus bernacchii, T. hansoni, T. newnesi) were analysed for Contracaecum sp. larvae, whose genetic identification was undertaken using allozyme diagnostic markers (N = 1347) and sequences analysis of the mtDNA cox2 gene (519bp) (N = 496). No significant differences were found in the infection levels by C. osculatum sp. D and sp. E - genetically recognised - on a temporal scale (2011-2012 versus 1993-1994). Whereas, statistical significant differences were found between the occurrence of C. osculatum sp. D and C. osculatum sp. E in different fish species, independently by the two sampling periods. Indeed, C. osculatum sp. E resulted more prevalent in T. bernacchii; while, higher percentage of C. osculatum sp. D occurred in C. hamatus and T. hansoni. The two species showed also differences in the host infection site: C. osculatum sp. D showed higher perce, Il lavoro condotto per questa tesi di dottorato si inserisce nell'ambito del Progetto finanziato dal MIUR-PNRA 2009 dal titolo: "Diversità genetica spazio-temporale di endoparassiti delle regioni polari: uno studio per la valutazione dell'impatto dei cambiamenti globali sulle reti trofiche marine. La tesi, è costituita da un'introduzione generale che comprende l'attuale tassonomia, il ciclo biologico e la distribuzione geografica delle specie di nematodi appartenenti al genere Contracaecum. Nei capitoli successivi sono stati presentati i risultati delle ricerche che rappresentano un avanzamento rispetto allo Stato dell'Arte. Alcuni di questi risultati sono stati già pubblicati su riviste internazionali, pertanto si è ritenuto opportuno mantenere in questa tesi, la struttura di pubblicazione. Infine, nell'ultimo capitolo, è inserito un lavoro pubblicato che riguarda altri nematodi anisakidi, appartenenti al genere Anisakis. Il lavoro pur non essendo oggetto del titolo della tesi, è tuttavia inserito nel contesto delle ricerche sui nematodi anisakidi., Dottorato di ricerca in Ecologia e gestione delle risorse biologiche

Diversity among individuals in a population is an important feature linking vital rates with behaviour and spatial occupation. We measured the growth increments in the otolith of individual fishes collected on the annual fisheries survey PELGAS from 2001 to 2015. Individuals who grew larger at juvenile stage occupied later in life more off-shore habitats. Further, we analysed the allozymes of 13 different loci from 2001 to 2006. Alleles of the enzyme IDH showed different frequencies in inshore and offshore habitats. The population spatially segregates along a coast to off-shore gradient with individuals showing different early growth and allele frequencies. Results show how individuals in a population segregate spatially in different habitats in relation with phenotypic diversity. This implies modelling the population with individual-based and physiological approaches to fully grasp its dynamics. It also implies developing management strategies to conserve infra-population diversity as a means to garantee the occupation of the full range of habitats.

African leafy vegetables are becoming important crops in tackling nutrition and food security in many parts of sub-Saharan Africa, since they provide important micronutrients and vitamins, and help resource-poor farm families bridge lean periods of food shortage. Genetic diversity studies are essential for crop improvement programmes as well as germplasm conservation efforts, and research on genetic diversity of these vegetables using molecular markers has been increasing over time. Diversity studies have evolved from the use of morphological and biochemical markers to molecular markers. Molecular markers provide valuable data, since they detect mostly selectively neutral variations at the DNA level. They are well established and their strengths and limitations have been described. New marker types are being developed from a combination of the strengths of the basic techniques to improve sensitivity, reproducibility, polymorphic information content, speed and cost. This review discusses the principles of some of the established molecular markers and their application to genetic diversity studies of African leafy vegetables with a main focus on the most common Solanum, Amaranthus, Cleome and Vigna species.

Diversity among individuals in a population is an important feature linking vital rates with behaviour and spatial occupation. We measured the growth increments in the otolith of individual fishes collected on the annual fisheries survey PELGAS from 2001 to 2015. Individuals who grew larger at juvenile stage occupied later in life more off-shore habitats. Further, we analysed the allozymes of 13 different loci from 2001 to 2006. Alleles of the enzyme IDH showed different frequencies in inshore and offshore habitats. The population spatially segregates along a coast to off-shore gradient with individuals showing different early growth and allele frequencies. Results show how individuals in a population segregate spatially in different habitats in relation with phenotypic diversity. This implies modelling the population with individual-based and physiological approaches to fully grasp its dynamics. It also implies developing management strategies to conserve infra-population diversity as a means to garantee the occupation of the full range of habitats.

We used allozymes to investigate the structure of genetic variation in populations of the perennial herb Silene nutans at local (Denmark), regional (Nordic area) and wide (over a 19° latitudinal gradient) geographic scales in north-western Europe. New data from Denmark were combined with data from previously studied Fennoscandian and western populations. We related patterns of nuclear variation for 26 Fennoscandian and western populations to the phylogeographic patterns revealed by four plastid (chloroplast) DNA markers. Levels of genetic diversity were similar within Denmark and Sweden/N Finland. Compared to Sweden/N Finland, the Danish populations show lower and nonsignificant FIS values. The genetic structure reveals no grouping of the Danish populations according to their geographic origin (Jutland-Zealand). Within Nordic populations (from Denmark, Sweden and N Finland), there is a weak geographic pattern of allozyme differentiation. The high latitude populations are genetically depauperate compared with populations from Western Europe. At the whole north-western European scale, the structure of allozyme variation within S. nutans shows geographic differentiation (Nordic versus western populations), and some congruence with plastid phylogeographic patterns. A high level of allozyme genetic differentiation is found between Nordic and western populations (8.0 %), but also between populations within haplotype categories (19.4 %). The overall geographic structure of allozyme variation of S. nutans appears to be primarily a reflection of past (postglacial) migration history, whereas more recent adaptive and stochastic processes have occurred at more local scales., SCOPUS: ar.j, info:eu-repo/semantics/published

Diversity among individuals in a population is an important feature linking vital rates with behaviour and spatial occupation. We measured the growth increments in the otolith of individual fishes collected on the annual fisheries survey PELGAS from 2001 to 2015. Individuals who grew larger at juvenile stage occupied later in life more off-shore habitats. Further, we analysed the allozymes of 13 different loci from 2001 to 2006. Alleles of the enzyme IDH showed different frequencies in inshore and offshore habitats. The population spatially segregates along a coast to off-shore gradient with individuals showing different early growth and allele frequencies. Results show how individuals in a population segregate spatially in different habitats in relation with phenotypic diversity. This implies modelling the population with individual-based and physiological approaches to fully grasp its dynamics. It also implies developing management strategies to conserve infra-population diversity as a means to garantee the occupation of the full range of habitats.

Diversity among individuals in a population is an important feature linking vital rates with behaviour and spatial occupation. We measured the growth increments in the otolith of individual fishes collected on the annual fisheries survey PELGAS from 2001 to 2015. Individuals who grew larger at juvenile stage occupied later in life more off-shore habitats. Further, we analysed the allozymes of 13 different loci from 2001 to 2006. Alleles of the enzyme IDH showed different frequencies in inshore and offshore habitats. The population spatially segregates along a coast to off-shore gradient with individuals showing different early growth and allele frequencies. Results show how individuals in a population segregate spatially in different habitats in relation with phenotypic diversity. This implies modelling the population with individual-based and physiological approaches to fully grasp its dynamics. It also implies developing management strategies to conserve infra-population diversity as a means to garantee the occupation of the full range of habitats.

The main Korean mountain range (the so-called >Baekdudaegan>), which stretches from north to south across most of the Peninsula, has been thought to harbor glacial refugia for boreal and temperate plant species, where they likely found relatively stable habitats and maintained large population sizes. Under this scenario, high levels of genetic variation for plant populations can be anticipated. To test this hypothesis, we examined levels of allozyme diversity in the boreal herb Lilium distichum, which in Korea occurs largely along the Baekdudaegan and in its closely related congener L. tsingtauense, a temperate species that can occur from the coastal islands to high-altitude mountains in the Baekdudaegan. As expected, L. distichum harbored high levels of genetic variation within populations, and we found significant correlations between percentage of polymorphic loci (and allelic richness) and elevation. For L. tsingtauense we found moderate genetic variation, with its populations showing a significantly positive correlation between intra-population expected heterozygosity and elevation. Our results suggest that populations/species that occur within or near the main ridge of the Baekdudaegan probably endured the glacial periods in macrorefugia, whereas those populations/species located at low elevations (far away from mid- and high-elevation mountains) did it in microrefugia. Palaeodistribution modelling is in agreement with genetic data, indicating that the Baekdudaegan was suitable habitat for both species during the glacial (LGM) and interglacial periods (like the present). This study as well as the data from other studies compiled here provides strong evidence that the Baekdudaegan was a major refugial area for the East Asian flora throughout the Quaternary and, thus, meriting high priority for conservation biogeography. © 2014 Elsevier GmbH.

The main Korean mountain range that stretches from north to south (the Baekdudaegan) has been suggested to harbor an important glacial refugium for boreal and temperate plant species. Under this scenario, we expect high levels of within-population genetic variation and low or moderate degree of among-population differentiation within these species. To test this hypothesis, we examined clonal diversity and levels of allozyme diversity in the boreal Iris odaesanensis and in its temperate congener Iris rossii. In addition, we compiled data on boreal and temperate species whose distribution in the Korean Peninsula is mostly centered in the Baekdudaegan to determine if there is a common pattern. We found lower clonal diversity in I. odaesanensis compared to I. rossii. Both studied species maintained high levels of genetic variation as well as a moderate genetic differentiation (%P = 52.5 and 47.5, A = 1.70 and 1.58, H e = 0.158 and 0.150, and F ST = 0.196 and 0.189 for I. odaesanensis and I. rossii, respectively), in line with what occurs for the species distributed on the Baekdudaegan (n = 14, %P = 46.7, A = 1.73, H e = 0.161, and F ST = 0.190). This study strongly suggests that the Baekdudaegan may have acted as a refugium for boreal and temperate species, in a similar way to the southern Appalachians in the eastern United States.

Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like ecology and conservation biology. We here review molecular genetic evidence relevant to the systematics of toads in the Bufo bufo species group (Anura, Bufonidae). Two studies recently published in this journal (Recuero et al., MPE 62: 71–86 and Garci´a-Porta et al., MPE 63: 113–130) addressed this issue but reached opposing conclusions on the taxonomy of the group (four versus two species). In particular, allozyme data in the latter paper were interpreted as evidence for hybridization across species (between B. bufo–B. spinosus and B. bufo–B. verrucosissimus). We tested claims for hybridization through re-analysis of allozyme data for individuals instead of populations, to be able to distinguish between sympatry with and without admixture, and found no evidence of hybridization across taxa. We propose alternative explanations for the observed patterns that Garci´a-Porta et al. (2012) failed to consider. In the absence of unequivocal evidence for hybridization and introgression, we reject the proposal to downgrade Bufo spinosus and Bufo verrucosissimus to the subspecies level.

The hermaphroditic terrestrial snail Rumina decollata has a mixed breeding system with a high prevalence of self-fertilization. In the Montpellier area (France), the species is represented by a dark and a light color morph. Based on allozyme data, both morphs have been reported as single, homozygous multilocus genotypes (MLG), differing at 13 out of 26 loci, but still showing occasional hybridization. Recent DNA sequence data suggest that each morph is a different phylogenetic species. In order to further evaluate this new taxonomic interpretation, the present contribution explores to what extent populations or color morphs indeed consist of single or few MLG. As such it is shown that both morphs are not single, homozygous MLG, but instead reveal a considerable amount of allelic variation and substantial numbers of heterozygous microsatellite genotypes. This suggests that outcrossing may be more prevalent than previously reported. Nevertheless, both morphs maintain a diagnostic multimarker differentiation in the presence of outcrossing in sympatric conditions, implying that they may be interpreted as species under the biological species concept. Finally, our data challenge the idea that simultaneous hermaphrodites should be either strict selfers or strict outcrossers. © 2013 Springer Science+Business Media Dordrecht., SCOPUS: ar.j, info:eu-repo/semantics/published

Tigerfish caudal fin colours vary from yellow to red, with distinct dissimilarities previously noted. To understand these colour differences, tigerfish were collected during 2008 to 2010 from four southern African populations in the Upper Zambezi River (ZAM), Okavango Delta (OKA), Pongolapoort Dam (POD) and Phongolo River (POR), and caudal fin colouration was classified according to pattern and sex. Muscle and liver tissue were assayed by starch electrophoresis. Caudal fin colour in OKA, ZAM and POD showed significant differences between sexes. Genetics revealed closer relationships between OKA and ZAM, substantiated by their recurrent and historical links, and between POD and POR, as expected for a dam and associated river. There is an association between the genetic and geographical distance of tigerfish populations, but variation in caudal colour in this species can most likely be attributed to their environment, territorial dominance and sexual behaviour.

Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like ecology and conservation biology. We here review molecular genetic evidence relevant to the systematics of toads in the Bufo bufo species group (Anura, Bufonidae). Two studies recently published in this journal (Recuero et al., MPE 62: 71–86 and Garci´a-Porta et al., MPE 63: 113–130) addressed this issue but reached opposing conclusions on the taxonomy of the group (four versus two species). In particular, allozyme data in the latter paper were interpreted as evidence for hybridization across species (between B. bufo–B. spinosus and B. bufo–B. verrucosissimus). We tested claims for hybridization through re-analysis of allozyme data for individuals instead of populations, to be able to distinguish between sympatry with and without admixture, and found no evidence of hybridization across taxa. We propose alternative explanations for the observed patterns that Garci´a-Porta et al. (2012) failed to consider. In the absence of unequivocal evidence for hybridization and introgression, we reject the proposal to downgrade Bufo spinosus and Bufo verrucosissimus to the subspecies level.

Tigerfish caudal fin colours vary from yellow to red, with distinct dissimilarities previously noted. To understand these colour differences, tigerfish were collected during 2008 to 2010 from four southern African populations in the Upper Zambezi River (ZAM), Okavango Delta (OKA), Pongolapoort Dam (POD) and Phongolo River (POR), and caudal fin colouration was classified according to pattern and sex. Muscle and liver tissue were assayed by starch electrophoresis. Caudal fin colour in OKA, ZAM and POD showed significant differences between sexes. Genetics revealed closer relationships between OKA and ZAM, substantiated by their recurrent and historical links, and between POD and POR, as expected for a dam and associated river. There is an association between the genetic and geographical distance of tigerfish populations, but variation in caudal colour in this species can most likely be attributed to their environment, territorial dominance and sexual behaviour.

Based on allozyme variation of 410 newly collected individuals from 52 localities, we reconstructed range-wide phylogeography of the widespread Western Palearctic anuran, Pelobates fuscus. To study genetic diversity, evolutionary history, postglacial range expansion and secondary contact zones, we used a multidisciplinary approach combining information from various genetic analyses and ecological niche modeling. We confirmed the presence of two main groups in P. fuscus, initially revealed by genome size variation. Pelobates f. vespertinus presents a monomorphic group, but two main groups can be identified in P. f. fuscus: an East European and a West European group. We suggest the existence of at least four different Last Glacial refugia for P. fuscus: (1) the area between the Caspian and Azov Seas as the origin for the expansion of P. f. vespertinus; (2) the northwestern part of the Black Sea area for the East European P. f. fuscus; (3) the southwestern part of the Pannonian Plain and (4) the Po Plain for the West European P. f. fuscus. The routes of postglacial range expansions from the refugia are discussed. We newly identified a hybrid zone between P. f. fuscus and P. f. vespertinus. The width of this zone is about 12.5 km. In light of these findings, the two subspecies of P. fuscus constitute distinct evolutionary lineages and merit recognition as separate species. Our data do not provide support for the validity of P.f. insubricus. We therefore propose to synonymize this subspecies with P. f. fuscus. © 2013 Gesellschaft für Biologische Systematik.

Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like ecology and conservation biology. We here review molecular genetic evidence relevant to the systematics of toads in the Bufo bufo species group (Anura, Bufonidae). Two studies recently published in this journal (Recuero et al., MPE 62: 71-86 and García-Porta et al., MPE 63: 113-130) addressed this issue but reached opposing conclusions on the taxonomy of the group (four versus two species). In particular, allozyme data in the latter paper were interpreted as evidence for hybridization across species (between B. bufo-B. spinosus and B. bufo-B. verrucosissimus). We tested claims for hybridization through re-analysis of allozyme data for individuals instead of populations, to be able to distinguish between sympatry with and without admixture, and found no evidence of hybridization across taxa. We propose alternative explanations for the observed patterns that García-Porta et al. (2012) failed to consider. In the absence of unequivocal evidence for hybridization and introgression, we reject the proposal to downgrade Bufo spinosus and Bufo verrucosissimus to the subspecies level.

The hermaphroditic terrestrial snail Rumina decollata has a mixed breeding system with a high prevalence of self-fertilization. In the Montpellier area (France), the species is represented by a dark and a light color morph. Based on allozyme data, both morphs have been reported as single, homozygous multilocus genotypes (MLG), differing at 13 out of 26 loci, but still showing occasional hybridization. Recent DNA sequence data suggest that each morph is a different phylogenetic species. In order to further evaluate this new taxonomic interpretation, the present contribution explores to what extent populations or color morphs indeed consist of single or few MLG. As such it is shown that both morphs are not single, homozygous MLG, but instead reveal a considerable amount of allelic variation and substantial numbers of heterozygous microsatellite genotypes. This suggests that outcrossing may be more prevalent than previously reported. Nevertheless, both morphs maintain a diagnostic multimarker differentiation in the presence of outcrossing in sympatric conditions, implying that they may be interpreted as species under the biological species concept. Finally, our data challenge the idea that simultaneous hermaphrodites should be either strict selfers or strict outcrossers. © 2013 Springer Science+Business Media Dordrecht., SCOPUS: ar.j, info:eu-repo/semantics/published

Background and Aims Archipelagos are unique systems for studying evolutionary processes promoting diversification and speciation. The islands of the Mediterranean basin are major areas of plant richness, including a high proportion of narrow endemics. Many endemic plants are currently found in rocky habitats, showing varying patterns of habitat occupancy at different spatial scales throughout their range. The aim of the present study was to understand the impact of varying patterns of population distribution on genetic diversity and structure to shed light on demographic and evolutionary processes leading to population diversification in Crepis triasii, an endemic plant from the eastern Balearic Islands. Methods Using allozyme and chloroplast markers, we related patterns of genetic structure and diversity to those of habitat occupancy at a regional (between islands and among populations within islands) and landscape (population size and connectivity) scale. Key Results Genetic diversity was highly structured both at the regional and at the landscape level, and was positively correlated with population connectivity in the landscape. Populations located in small isolated mountains and coastal areas, with restricted patterns of regional occupancy, were genetically less diverse and much more differentiated. In addition, more isolated populations had stronger fine-scale genetic structure than well-connected ones. Changes in habitat availability and quality arising from marine transgressions during the Quaternary, as well as progressive fragmentation associated with the aridification of the climate since the last glaciation, are the most plausible factors leading to the observed patterns of genetic diversity and structure. Conclusions Our results emphasize the importance of gene flow in preventing genetic erosion and maintaining the evolutionary potential of populations. They also agree with recent studies highlighting the importance of restricted gene flow and genetic dr

Slender salamanders of the genus Batrachoseps achieve relatively high diversity in the Kern Canyon region at the southern end of the Sierra Nevada of California through high turnover of species with small geographic ranges. The status of several populations of Batrachoseps in this region is enigmatic, and both morphological and molecular data have suggested that some populations do not belong to any of the currently recognized species. Identification of species in this region is com-plicated by the apparent extinction of Batrachoseps relictus in the vicinity of its type locality in the Lower Kern River Canyon. Here we analyze a comprehensive morphological dataset to evaluate diversity in the Kern River Canyon region. We conclude that populations from Breckenridge Mountain are conspecific with B. relictus, while populations from north of the Kern River previously treated as B. relictus belong to an undescribed species. The morphological data also show the distinctiveness of populations from the Upper Kern River Canyon. Thus, we describe two new species, Batrachoseps bramei sp. nov. for populations from the Upper Kern River Canyon and Batrachoseps altasierrae sp. nov. for populations from the southern Sierra Nevada previously referred to B. relictus. B. bramei sp. nov. and B. relictus are members of the nigriventris group; B. altasierrae sp. nov. belongs to the group formerly called the relictus group, which we rename the diabolicus group. We conclude by presenting allozyme and mitochondrial DNA sequence data that support the distinc-tiveness of these newly described species and provide a hypothesis of relationships within the nigriventris group

The phylogenetic relationships between naturally occurring Atlantic Crassostrea oyster species were inferred through analyses of mitochondrial (cytochrome oxidase subunit I and 16S) and nuclear (second internal transcribed spacer) sequences. We also scored 15 allozyme loci on 422 oysters to study population structuring of C. rhizophorae and C. brasiliana along 9000 km of the Western Atlantic coastline. Despite morphological similarities, C. virginica was genetically more closely related to C. rhizophorae than to C. brasiliana. In contrast, C. paraibanensis was genetically indistinguishable from C. brasiliana, which is probably a junior synonym of the African C. gasar. Significant genetic differentiation between populations of C. rhizophorae and C. gasar were found along the Western Atlantic coast, supporting an isolation-by-distance pattern.

Recent reviews have shown that hybridisation among ant species is likely to be more common than previously appreci-ated, but that documented cases of introgression remain rare. After molecular phylogenetic work had shown that Euro-pean Lasius niger (LINNAEUS, 1758) and L. psammophilus SEIFERT, 1992 (formerly L. alienus (FOERSTER, 1850)) are unlikely to be very closely related, we decided to analyse an old data set confirming the conclusion by PEARSON (1983) that these two ants can indeed form viable hybrids. We show that signatures of introgression can be detected in a Danish site and that interspecific gene-flow is asymmetrical (only from L. niger into L. psammophilus) as inferred previously by Pearson for the southern England site that he studied and from which we also collected data. We compare the ob-served patterns of hybridisation and introgression in the Danish and British site and infer that overlap in nuptial flights in Denmark may have contributed to the higher frequency of introgressed genes relative to the southern England site where nuptial flights are clearly separated in time. We also report the first mating system data for L. psammophilus, showing that this species has facultative multiple mating of queens similar to L. niger. We suggest that L. psammophilus-niger introgression may be much more common than previously appreciated, which would explain that European myr-mecologists have often found it difficult to distinguish between these species at sites where they occur sympatrically. This would imply that multiple accessible field sites are available to study the molecular details of hybridisation and in-trogression between two ant species that have variable degrees of sympatry throughout their distributional ranges

Coral reefs belong to the most diverse and the most threatened ecosystems on earth. Anthropogenic stressors and climate change have led to mortalities at levels unprecedented in modern times. The aims of this thesis are to investigate aspects of the corals’ ability to reproduce, disperse, adapt and survive. Papers I-III study reproduction in a common soft coral species, Sarcophyton elegans, with previously unknown reproductive modes. Paper IV investigates genetic distribution of coral-symbiont associations in Galaxea fascicularis focusing on adaptation to the environment along the coastline of Vietnam. Sarcophyton elegans is a gonochoric broadcast spawner with a 1:1 sex ratio. Reproduction is strictly size dependent. Oogenesis takes 19-24 months, with a new cycle commencing every year. Spermatogenesis takes 10-12 months. The majority of gametes were released during the annual austral mass spawning event after full moon in November, but spawning also occur between August and February. The polyps at the outer edge of the colonies released their gametes first, followed by polyps situated closer to the center during subsequent months. Colonies upstream in the prevailing current spawn earlier than those downstream. The colonies were arranged in clusters of alternating males and females, which spawned simultaneously and were of the same genotype. Fission and buddying is a common mode to expand locally. Additionally, females undergoing fission divided into the most fecund size classes. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors. The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. The study highlights the importance of protecting resilient coral and algal genotypes in stressed a, Các rạn san hô là một trong những hệ sinh thái có tính đa dạng và bị đe dọa cao nhất trên trái đất. Các áp lực từ con người và nhiệt độ nước biển tăng (SSTs) đã gây ra hiện tượng “tẩy trắng” gây chết san hô ở mức độ cao chưa từng thấy trong thời điểm hiện tại. Mục tiêu của nghiên cứu này là tìm hiểu khả năng của san hô trong thích nghi, phân tán và sống sót nhằm duy trì quần thể. Bài báo số II-III là những nghiên cứu đầu tiên về đặc điểm sinh sản của loài san hô mềm phổ biến, Sarcophyton elegan tại Australia. Bài báo số IV nghiên cứu về phân bố nguồn gen của tảo cộng sinh trong loài san hô Galaxea fascicularis, tập trung vào sự thích nghi với môi trường dọc theo vùng biển Việt Nam, khu vực bị ô nhiễm từ lục địa. Sarcophyton elegans được biết với đặc điểm sinh sản cả vô tính và hữu tính. Loài này là loài sinh sản bằng cách phân tán trứng, với tỷ lệ giới tính là 1:1 và sự sinh sản hữu tính bị khống chế nghiêm ngặt bởi kích cỡ của tập đoàn (Bài báo II, phần phương pháp của Bài báo I). Quá trình tạo trứng kéo dài từ 19 đến 24 tháng với chu kỳ sinh sản lặp lại hàng năm, và sự sinh tinh kéo dài từ 10 đến 12 tháng. Phần lớn giao tử được giải phóng trong một thời gian ngắn sau ngày trăng tròn của tháng 11, nhưng giao tử vẫn được giải phóng trong ngày trăng tròn của các tháng từ tháng 8 đến tháng 1 năm sau. Các polyp autozooid nằm phía ngoài của tập đoàn giải phóng giao tử trước, sau đó là các polyp nằm gần lõi trong các tháng tiếp theo. Các tập đoàn ngược lên trong dòng chảy thịnh hành đẻ trứng sớm hơn các tập đoàn xuôi dòng khoảng một tháng (Bài báo II). Các tập đoàn được sắp xếp thành từng đám từ 7 đến hàng trăm tập đoàn trong mỗi nhóm, bao gồm cả đực và cái. Các tập đoàn trong cùng một nhóm sinh sản cùng một thời điểm. (Bài báo II) và mỗi nhóm có cùng một kiểu di truyền (Bài báo III) có đầy đủ 13 (có thể là 22) kiểu di truyền khác nhau. Sự phân đôi và kết đôi phụ thuộc hoàn toàn vào kích thước và có lẽ là phương thức mở rộng phổ biến nhất. Sự phân đôi phải mất 2 năm hoặ, At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Recent reviews have shown that hybridisation among ant species is likely to be more common than previously appreci-ated, but that documented cases of introgression remain rare. After molecular phylogenetic work had shown that Euro-pean Lasius niger (LINNAEUS, 1758) and L. psammophilus SEIFERT, 1992 (formerly L. alienus (FOERSTER, 1850)) are unlikely to be very closely related, we decided to analyse an old data set confirming the conclusion by PEARSON (1983) that these two ants can indeed form viable hybrids. We show that signatures of introgression can be detected in a Danish site and that interspecific gene-flow is asymmetrical (only from L. niger into L. psammophilus) as inferred previously by Pearson for the southern England site that he studied and from which we also collected data. We compare the ob-served patterns of hybridisation and introgression in the Danish and British site and infer that overlap in nuptial flights in Denmark may have contributed to the higher frequency of introgressed genes relative to the southern England site where nuptial flights are clearly separated in time. We also report the first mating system data for L. psammophilus, showing that this species has facultative multiple mating of queens similar to L. niger. We suggest that L. psammophilus-niger introgression may be much more common than previously appreciated, which would explain that European myr-mecologists have often found it difficult to distinguish between these species at sites where they occur sympatrically. This would imply that multiple accessible field sites are available to study the molecular details of hybridisation and in-trogression between two ant species that have variable degrees of sympatry throughout their distributional ranges

Coral reefs belong to the most diverse and the most threatened ecosystems on earth. Anthropogenic stressors and climate change have led to mortalities at levels unprecedented in modern times. The aims of this thesis are to investigate aspects of the corals’ ability to reproduce, disperse, adapt and survive. Papers I-III study reproduction in a common soft coral species, Sarcophyton elegans, with previously unknown reproductive modes. Paper IV investigates genetic distribution of coral-symbiont associations in Galaxea fascicularis focusing on adaptation to the environment along the coastline of Vietnam. Sarcophyton elegans is a gonochoric broadcast spawner with a 1:1 sex ratio. Reproduction is strictly size dependent. Oogenesis takes 19-24 months, with a new cycle commencing every year. Spermatogenesis takes 10-12 months. The majority of gametes were released during the annual austral mass spawning event after full moon in November, but spawning also occur between August and February. The polyps at the outer edge of the colonies released their gametes first, followed by polyps situated closer to the center during subsequent months. Colonies upstream in the prevailing current spawn earlier than those downstream. The colonies were arranged in clusters of alternating males and females, which spawned simultaneously and were of the same genotype. Fission and buddying is a common mode to expand locally. Additionally, females undergoing fission divided into the most fecund size classes. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors. The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. The study highlights the importance of protecting resilient coral and algal genotypes in stressed a, Các rạn san hô là một trong những hệ sinh thái có tính đa dạng và bị đe dọa cao nhất trên trái đất. Các áp lực từ con người và nhiệt độ nước biển tăng (SSTs) đã gây ra hiện tượng “tẩy trắng” gây chết san hô ở mức độ cao chưa từng thấy trong thời điểm hiện tại. Mục tiêu của nghiên cứu này là tìm hiểu khả năng của san hô trong thích nghi, phân tán và sống sót nhằm duy trì quần thể. Bài báo số II-III là những nghiên cứu đầu tiên về đặc điểm sinh sản của loài san hô mềm phổ biến, Sarcophyton elegan tại Australia. Bài báo số IV nghiên cứu về phân bố nguồn gen của tảo cộng sinh trong loài san hô Galaxea fascicularis, tập trung vào sự thích nghi với môi trường dọc theo vùng biển Việt Nam, khu vực bị ô nhiễm từ lục địa. Sarcophyton elegans được biết với đặc điểm sinh sản cả vô tính và hữu tính. Loài này là loài sinh sản bằng cách phân tán trứng, với tỷ lệ giới tính là 1:1 và sự sinh sản hữu tính bị khống chế nghiêm ngặt bởi kích cỡ của tập đoàn (Bài báo II, phần phương pháp của Bài báo I). Quá trình tạo trứng kéo dài từ 19 đến 24 tháng với chu kỳ sinh sản lặp lại hàng năm, và sự sinh tinh kéo dài từ 10 đến 12 tháng. Phần lớn giao tử được giải phóng trong một thời gian ngắn sau ngày trăng tròn của tháng 11, nhưng giao tử vẫn được giải phóng trong ngày trăng tròn của các tháng từ tháng 8 đến tháng 1 năm sau. Các polyp autozooid nằm phía ngoài của tập đoàn giải phóng giao tử trước, sau đó là các polyp nằm gần lõi trong các tháng tiếp theo. Các tập đoàn ngược lên trong dòng chảy thịnh hành đẻ trứng sớm hơn các tập đoàn xuôi dòng khoảng một tháng (Bài báo II). Các tập đoàn được sắp xếp thành từng đám từ 7 đến hàng trăm tập đoàn trong mỗi nhóm, bao gồm cả đực và cái. Các tập đoàn trong cùng một nhóm sinh sản cùng một thời điểm. (Bài báo II) và mỗi nhóm có cùng một kiểu di truyền (Bài báo III) có đầy đủ 13 (có thể là 22) kiểu di truyền khác nhau. Sự phân đôi và kết đôi phụ thuộc hoàn toàn vào kích thước và có lẽ là phương thức mở rộng phổ biến nhất. Sự phân đôi phải mất 2 năm hoặ, At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Aim The main aim of the present study is to infer the post-glacial history of Abies species from north-east Asia and to test the hypotheses that coastal Abies populations suffered less from climatic fluctuations during Pleistocene glacial periods than their more continental counterparts, and that Sakhalin was a major area of introgression. Location Natural ranges of the fir species Abies nephrolepis, Abies sachalinensis and Abies holophylla in the Russian Far East, and of Abies gracilis, which is endemic to the Kamchatka Peninsula. Methods Nineteen populations were sampled for allozyme analysis. Seventeen of these populations were also screened for variation at two paternally inherited chloroplast DNA microsatellite loci (cpSSR) and variation at one maternally inherited mitochondrial marker (nad4-3/4). Finally a subset of 11 populations was analysed with amplified fragment length polymorphism (AFLP). Comparisons were made with already available Abies sibirica data. For all sets of markers, we estimated genetic diversity and differentiation using an analysis of molecular variance (AMOVA). Population clustering was assessed with a Bayesian approach implemented in structure v.2.3. Results Among the three major species, A. sibirica, A. nephrolepis and A. sachalinensis, A. sachalinensis demonstrated the highest cytoplasmic and nuclear diversity and the most continental species, A. sibirica, the lowest. Both nuclear and mitochondrial DNA markers revealed the presence of a transitional zone on Sakhalin Island between A. nephrolepis and A. sachalinensis of south Sakhalin. The structure analysis delivered very clear results confirming the admixed origin of A. sachalinensis, with a genetic contribution from A. nephrolepis. No variation in cytoplasmic markers was found in A. gracilis, suggesting the occurrence of a recent bottleneck. Main conclusions There is a clear reduction of genetic diversity in Abies species from the Pacific coast into the continent. The higher diversity

Coral reefs belong to the most diverse and the most threatened ecosystems on earth. Anthropogenic stressors and climate change have led to mortalities at levels unprecedented in modern times. The aims of this thesis are to investigate aspects of the corals’ ability to reproduce, disperse, adapt and survive. Papers I-III study reproduction in a common soft coral species, Sarcophyton elegans, with previously unknown reproductive modes. Paper IV investigates genetic distribution of coral-symbiont associations in Galaxea fascicularis focusing on adaptation to the environment along the coastline of Vietnam. Sarcophyton elegans is a gonochoric broadcast spawner with a 1:1 sex ratio. Reproduction is strictly size dependent. Oogenesis takes 19-24 months, with a new cycle commencing every year. Spermatogenesis takes 10-12 months. The majority of gametes were released during the annual austral mass spawning event after full moon in November, but spawning also occur between August and February. The polyps at the outer edge of the colonies released their gametes first, followed by polyps situated closer to the center during subsequent months. Colonies upstream in the prevailing current spawn earlier than those downstream. The colonies were arranged in clusters of alternating males and females, which spawned simultaneously and were of the same genotype. Fission and buddying is a common mode to expand locally. Additionally, females undergoing fission divided into the most fecund size classes. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors. The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. The study highlights the importance of protecting resilient coral and algal genotypes in stressed a, Các rạn san hô là một trong những hệ sinh thái có tính đa dạng và bị đe dọa cao nhất trên trái đất. Các áp lực từ con người và nhiệt độ nước biển tăng (SSTs) đã gây ra hiện tượng “tẩy trắng” gây chết san hô ở mức độ cao chưa từng thấy trong thời điểm hiện tại. Mục tiêu của nghiên cứu này là tìm hiểu khả năng của san hô trong thích nghi, phân tán và sống sót nhằm duy trì quần thể. Bài báo số II-III là những nghiên cứu đầu tiên về đặc điểm sinh sản của loài san hô mềm phổ biến, Sarcophyton elegan tại Australia. Bài báo số IV nghiên cứu về phân bố nguồn gen của tảo cộng sinh trong loài san hô Galaxea fascicularis, tập trung vào sự thích nghi với môi trường dọc theo vùng biển Việt Nam, khu vực bị ô nhiễm từ lục địa. Sarcophyton elegans được biết với đặc điểm sinh sản cả vô tính và hữu tính. Loài này là loài sinh sản bằng cách phân tán trứng, với tỷ lệ giới tính là 1:1 và sự sinh sản hữu tính bị khống chế nghiêm ngặt bởi kích cỡ của tập đoàn (Bài báo II, phần phương pháp của Bài báo I). Quá trình tạo trứng kéo dài từ 19 đến 24 tháng với chu kỳ sinh sản lặp lại hàng năm, và sự sinh tinh kéo dài từ 10 đến 12 tháng. Phần lớn giao tử được giải phóng trong một thời gian ngắn sau ngày trăng tròn của tháng 11, nhưng giao tử vẫn được giải phóng trong ngày trăng tròn của các tháng từ tháng 8 đến tháng 1 năm sau. Các polyp autozooid nằm phía ngoài của tập đoàn giải phóng giao tử trước, sau đó là các polyp nằm gần lõi trong các tháng tiếp theo. Các tập đoàn ngược lên trong dòng chảy thịnh hành đẻ trứng sớm hơn các tập đoàn xuôi dòng khoảng một tháng (Bài báo II). Các tập đoàn được sắp xếp thành từng đám từ 7 đến hàng trăm tập đoàn trong mỗi nhóm, bao gồm cả đực và cái. Các tập đoàn trong cùng một nhóm sinh sản cùng một thời điểm. (Bài báo II) và mỗi nhóm có cùng một kiểu di truyền (Bài báo III) có đầy đủ 13 (có thể là 22) kiểu di truyền khác nhau. Sự phân đôi và kết đôi phụ thuộc hoàn toàn vào kích thước và có lẽ là phương thức mở rộng phổ biến nhất. Sự phân đôi phải mất 2 năm hoặ, At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Coral reefs belong to the most diverse and the most threatened ecosystems on earth. Anthropogenic stressors and climate change have led to mortalities at levels unprecedented in modern times. The aims of this thesis are to investigate aspects of the corals’ ability to reproduce, disperse, adapt and survive. Papers I-III study reproduction in a common soft coral species, Sarcophyton elegans, with previously unknown reproductive modes. Paper IV investigates genetic distribution of coral-symbiont associations in Galaxea fascicularis focusing on adaptation to the environment along the coastline of Vietnam. Sarcophyton elegans is a gonochoric broadcast spawner with a 1:1 sex ratio. Reproduction is strictly size dependent. Oogenesis takes 19-24 months, with a new cycle commencing every year. Spermatogenesis takes 10-12 months. The majority of gametes were released during the annual austral mass spawning event after full moon in November, but spawning also occur between August and February. The polyps at the outer edge of the colonies released their gametes first, followed by polyps situated closer to the center during subsequent months. Colonies upstream in the prevailing current spawn earlier than those downstream. The colonies were arranged in clusters of alternating males and females, which spawned simultaneously and were of the same genotype. Fission and buddying is a common mode to expand locally. Additionally, females undergoing fission divided into the most fecund size classes. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors. The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. The study highlights the importance of protecting resilient coral and algal genotypes in stressed a, Các rạn san hô là một trong những hệ sinh thái có tính đa dạng và bị đe dọa cao nhất trên trái đất. Các áp lực từ con người và nhiệt độ nước biển tăng (SSTs) đã gây ra hiện tượng “tẩy trắng” gây chết san hô ở mức độ cao chưa từng thấy trong thời điểm hiện tại. Mục tiêu của nghiên cứu này là tìm hiểu khả năng của san hô trong thích nghi, phân tán và sống sót nhằm duy trì quần thể. Bài báo số II-III là những nghiên cứu đầu tiên về đặc điểm sinh sản của loài san hô mềm phổ biến, Sarcophyton elegan tại Australia. Bài báo số IV nghiên cứu về phân bố nguồn gen của tảo cộng sinh trong loài san hô Galaxea fascicularis, tập trung vào sự thích nghi với môi trường dọc theo vùng biển Việt Nam, khu vực bị ô nhiễm từ lục địa. Sarcophyton elegans được biết với đặc điểm sinh sản cả vô tính và hữu tính. Loài này là loài sinh sản bằng cách phân tán trứng, với tỷ lệ giới tính là 1:1 và sự sinh sản hữu tính bị khống chế nghiêm ngặt bởi kích cỡ của tập đoàn (Bài báo II, phần phương pháp của Bài báo I). Quá trình tạo trứng kéo dài từ 19 đến 24 tháng với chu kỳ sinh sản lặp lại hàng năm, và sự sinh tinh kéo dài từ 10 đến 12 tháng. Phần lớn giao tử được giải phóng trong một thời gian ngắn sau ngày trăng tròn của tháng 11, nhưng giao tử vẫn được giải phóng trong ngày trăng tròn của các tháng từ tháng 8 đến tháng 1 năm sau. Các polyp autozooid nằm phía ngoài của tập đoàn giải phóng giao tử trước, sau đó là các polyp nằm gần lõi trong các tháng tiếp theo. Các tập đoàn ngược lên trong dòng chảy thịnh hành đẻ trứng sớm hơn các tập đoàn xuôi dòng khoảng một tháng (Bài báo II). Các tập đoàn được sắp xếp thành từng đám từ 7 đến hàng trăm tập đoàn trong mỗi nhóm, bao gồm cả đực và cái. Các tập đoàn trong cùng một nhóm sinh sản cùng một thời điểm. (Bài báo II) và mỗi nhóm có cùng một kiểu di truyền (Bài báo III) có đầy đủ 13 (có thể là 22) kiểu di truyền khác nhau. Sự phân đôi và kết đôi phụ thuộc hoàn toàn vào kích thước và có lẽ là phương thức mở rộng phổ biến nhất. Sự phân đôi phải mất 2 năm hoặ, At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Coral reefs belong to the most diverse and the most threatened ecosystems on earth. Anthropogenic stressors and climate change have led to mortalities at levels unprecedented in modern times. The aims of this thesis are to investigate aspects of the corals’ ability to reproduce, disperse, adapt and survive. Papers I-III study reproduction in a common soft coral species, Sarcophyton elegans, with previously unknown reproductive modes. Paper IV investigates genetic distribution of coral-symbiont associations in Galaxea fascicularis focusing on adaptation to the environment along the coastline of Vietnam. Sarcophyton elegans is a gonochoric broadcast spawner with a 1:1 sex ratio. Reproduction is strictly size dependent. Oogenesis takes 19-24 months, with a new cycle commencing every year. Spermatogenesis takes 10-12 months. The majority of gametes were released during the annual austral mass spawning event after full moon in November, but spawning also occur between August and February. The polyps at the outer edge of the colonies released their gametes first, followed by polyps situated closer to the center during subsequent months. Colonies upstream in the prevailing current spawn earlier than those downstream. The colonies were arranged in clusters of alternating males and females, which spawned simultaneously and were of the same genotype. Fission and buddying is a common mode to expand locally. Additionally, females undergoing fission divided into the most fecund size classes. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors. The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. The study highlights the importance of protecting resilient coral and algal genotypes in stressed a, Các rạn san hô là một trong những hệ sinh thái có tính đa dạng và bị đe dọa cao nhất trên trái đất. Các áp lực từ con người và nhiệt độ nước biển tăng (SSTs) đã gây ra hiện tượng “tẩy trắng” gây chết san hô ở mức độ cao chưa từng thấy trong thời điểm hiện tại. Mục tiêu của nghiên cứu này là tìm hiểu khả năng của san hô trong thích nghi, phân tán và sống sót nhằm duy trì quần thể. Bài báo số II-III là những nghiên cứu đầu tiên về đặc điểm sinh sản của loài san hô mềm phổ biến, Sarcophyton elegan tại Australia. Bài báo số IV nghiên cứu về phân bố nguồn gen của tảo cộng sinh trong loài san hô Galaxea fascicularis, tập trung vào sự thích nghi với môi trường dọc theo vùng biển Việt Nam, khu vực bị ô nhiễm từ lục địa. Sarcophyton elegans được biết với đặc điểm sinh sản cả vô tính và hữu tính. Loài này là loài sinh sản bằng cách phân tán trứng, với tỷ lệ giới tính là 1:1 và sự sinh sản hữu tính bị khống chế nghiêm ngặt bởi kích cỡ của tập đoàn (Bài báo II, phần phương pháp của Bài báo I). Quá trình tạo trứng kéo dài từ 19 đến 24 tháng với chu kỳ sinh sản lặp lại hàng năm, và sự sinh tinh kéo dài từ 10 đến 12 tháng. Phần lớn giao tử được giải phóng trong một thời gian ngắn sau ngày trăng tròn của tháng 11, nhưng giao tử vẫn được giải phóng trong ngày trăng tròn của các tháng từ tháng 8 đến tháng 1 năm sau. Các polyp autozooid nằm phía ngoài của tập đoàn giải phóng giao tử trước, sau đó là các polyp nằm gần lõi trong các tháng tiếp theo. Các tập đoàn ngược lên trong dòng chảy thịnh hành đẻ trứng sớm hơn các tập đoàn xuôi dòng khoảng một tháng (Bài báo II). Các tập đoàn được sắp xếp thành từng đám từ 7 đến hàng trăm tập đoàn trong mỗi nhóm, bao gồm cả đực và cái. Các tập đoàn trong cùng một nhóm sinh sản cùng một thời điểm. (Bài báo II) và mỗi nhóm có cùng một kiểu di truyền (Bài báo III) có đầy đủ 13 (có thể là 22) kiểu di truyền khác nhau. Sự phân đôi và kết đôi phụ thuộc hoàn toàn vào kích thước và có lẽ là phương thức mở rộng phổ biến nhất. Sự phân đôi phải mất 2 năm hoặ, At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Recent reviews have shown that hybridisation among ant species is likely to be more common than previously appreci-ated, but that documented cases of introgression remain rare. After molecular phylogenetic work had shown that Euro-pean Lasius niger (LINNAEUS, 1758) and L. psammophilus SEIFERT, 1992 (formerly L. alienus (FOERSTER, 1850)) are unlikely to be very closely related, we decided to analyse an old data set confirming the conclusion by PEARSON (1983) that these two ants can indeed form viable hybrids. We show that signatures of introgression can be detected in a Danish site and that interspecific gene-flow is asymmetrical (only from L. niger into L. psammophilus) as inferred previously by Pearson for the southern England site that he studied and from which we also collected data. We compare the ob-served patterns of hybridisation and introgression in the Danish and British site and infer that overlap in nuptial flights in Denmark may have contributed to the higher frequency of introgressed genes relative to the southern England site where nuptial flights are clearly separated in time. We also report the first mating system data for L. psammophilus, showing that this species has facultative multiple mating of queens similar to L. niger. We suggest that L. psammophilus-niger introgression may be much more common than previously appreciated, which would explain that European myr-mecologists have often found it difficult to distinguish between these species at sites where they occur sympatrically. This would imply that multiple accessible field sites are available to study the molecular details of hybridisation and in-trogression between two ant species that have variable degrees of sympatry throughout their distributional ranges

The phylogenetic relationships between naturally occurring Atlantic Crassostrea oyster species were inferred through analyses of mitochondrial (cytochrome oxidase subunit I and 16S) and nuclear (second internal transcribed spacer) sequences. We also scored 15 allozyme loci on 422 oysters to study population structuring of C. rhizophorae and C. brasiliana along 9000 km of the Western Atlantic coastline. Despite morphological similarities, C. virginica was genetically more closely related to C. rhizophorae than to C. brasiliana. In contrast, C. paraibanensis was genetically indistinguishable from C. brasiliana, which is probably a junior synonym of the African C. gasar. Significant genetic differentiation between populations of C. rhizophorae and C. gasar were found along the Western Atlantic coast, supporting an isolation-by-distance pattern.

The phylogenetic relationships between naturally occurring Atlantic Crassostrea oyster species were inferred through analyses of mitochondrial (cytochrome oxidase subunit I and 16S) and nuclear (second internal transcribed spacer) sequences. We also scored 15 allozyme loci on 422 oysters to study population structuring of C. rhizophorae and C. brasiliana along 9000 km of the Western Atlantic coastline. Despite morphological similarities, C. virginica was genetically more closely related to C. rhizophorae than to C. brasiliana. In contrast, C. paraibanensis was genetically indistinguishable from C. brasiliana, which is probably a junior synonym of the African C. gasar. Significant genetic differentiation between populations of C. rhizophorae and C. gasar were found along the Western Atlantic coast, supporting an isolation-by-distance pattern.

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.

In a previous study, a major remodeling of lipids, consistent with the theory of homeoviscous adaptation, was observed in the juvenile hard clam Mercenaria mercenaria during a temperature reduction from 24 to -1 degrees C. In addition, the lipid remodeling varied between genetically distinct lines of hard clams. The present study examined whether adult hard clams originating from different locations and a selectively bred variety show differences related to their genetic characteristics in the remodeling of lipids that normally occur during decreasing temperatures. Wild hard clams from 4 locations in Atlantic Canada and the selectively bred M mercenaria var. notata were held at an aquaculture growout site located at the northern distribution limit of the species in the Gulf of St. Lawrence from August to December 2006. Gills were sampled monthly for lipid analyses. Hard clams from the 5 groups showed an increase in the unsaturation index, mainly attributable to 22:6n-3 and 20:5n-3 as temperature decreased during the fall, followed by an increase in the phospholipid to sterol ratio in December. Although hard clams from the wild showed a lower unsaturation index than the selectively bred clams, there was no effect of location on the lipid remodeling. This result coincided with low genetic differentiation among hard clams from the 5 groups. Interestingly, the levels of 20:5n-3, 20:4n-6 and 22:6n-3-3 fatty acids obtained from the diet-were generally lower in the environment compared to the levels in hard clams, thus suggesting some mechanisms for the selective incorporation of these fatty acids in hard clams.

The brook trout Salvelinus fontinalis is the only salmonid native to the southern Appalachian Mountains, and is distributed across eastern North America from Canada to Georgia. This species was once abundant in coldwater lakes and streams throughout its range, but environmental disturbances and the introduction of non-native species have drastically reduced the number and sizes of wild populations. Genetic evidence suggests a division at the subspecies level between southern- and northern-derived brook trout populations, with the break between the two forms occurring roughly at the New River watershed. Before the subspecies structure was recognized, brook trout of northern origin were widely stocked throughout the Southeast. The primary objective of this study was to determine the phylogenetic origin of all wild brook trout populations in southwestern Virginia using allozyme markers. Seventy-eight streams believed to contain brook trout in the New, James, Holston, and Yadkin river drainages were sampled by backpack electrofishing. Muscle tissue samples were collected from 916 individuals from 56 populations using a non-lethal biopsy technique. The samples were analyzed by cellulose acetate gel electrophoresis and histochemical staining techniques. Variation at four polymorphic loci, including the diagnostic creatine kinase (CK-A2*) locus, was quantified in terms of genetic diversity and population genetic differentiation. Allele frequencies indicated that 19 populations were of putative southern origin, 5 of northern origin, and 32 of mixed genetic origin. The secondary objective was to determine the geographic distribution of southern- and northern-form brook trout populations throughout the native range using data compiled from all known genetic studies. A map of these data showed that the break between the southern and northern form is sharp, occurring at the New/Roanoke-James watershed divide. Populations from the New River drainage expressed the s

The region around the Strait of Gibraltar is considered to be one of the most relevant 'hot spots' of biodiversity in the Mediterranean Basin due to its historical, biogeographical, and ecological features. Prominent among these is its role as a land bridge for the migration and differentiation of species during the Pleistocene, as a consequence of the lowering of sea level and climate changes associated with the Ice Ages. In the present study, we report a multilevel hierarchical investigation of the genetic diversity of Calicotome villosa, a common pioneer legume shrub, at the regional scale. The results of genetic analysis of progeny arrays are consistent with a predominantly outcrossing mating system in all the populations analysed. Geographically, a pattern of population isolation by distance was found, but the Strait accounted for only approximately 2% of the among-population genetic differentiation. Consequently, extensive historical gene flow appears to be the rule for this species in this area. According to the natural history traits of C. villosa (pollination, dispersal, and colonization ability), we hypothesize that gene flow must be strongly influenced by seed dispersal because pollen flow is very limited. Based on the history of trade and land use, cattle and human movements across the Strait must have strongly favoured seed dispersal. We review and discuss these results and compare them with those of other reported studies of genetic and phylogenetic differentiation across the Strait of Gibraltar. It is stressed that colonization ability, which depends upon seed dispersal and life form, can be a more critical factor in gene flow than pollination.