TY - THES A1 - Sammler, Svenja T1 - Molecular evolution and conservation genetics in the two Philippine hornbill species Aceros waldeni and Penelopides panini Y1 - 2012 CY - Potsdam ER - TY - THES A1 - Sammler, Svenja A1 - Ketmaier, Valerio A1 - Havenstein, Katja A1 - Krause, Ulrike A1 - Curio, Eberhard A1 - Tiedemann, Ralph T1 - Mitochondrial control region I and microsatellite analyses of endangered Philippine hornbill species (Aves; Bucerotidae) detect gene flow between island populations and genetic diversity loss Y1 - 2012 UR - http://www.biomedcentral.com/content/pdf/1471-2148-12-203.pdf U6 - https://doi.org/10.1186/1471-2148-12-203 ER - TY - JOUR A1 - Sammler, Svenja A1 - Ketmaier, Valerio A1 - Havenstein, Katja A1 - Krause, Ulrike A1 - Curio, Eberhard A1 - Tiedemann, Ralph T1 - Mitochondrial control region I and microsatellite analyses of endangered Philippine hornbill species (Aves; Bucerotidae) detect gene flow between island populations and genetic diversity loss JF - BMC evolutionary biology N2 - Background: The Visayan Tarictic Hornbill (Penelopides panini) and the Walden's Hornbill (Aceros waldeni) are two threatened hornbill species endemic to the western islands of the Visayas that constitute - between Luzon and Mindanao - the central island group of the Philippine archipelago. In order to evaluate their genetic diversity and to support efforts towards their conservation, we analyzed genetic variation in similar to 600 base pairs (bp) of the mitochondrial control region I and at 12-19 nuclear microsatellite loci. The sampling covered extant populations, still occurring only on two islands (P. panini: Panay and Negros, A. waldeni: only Panay), and it was augmented with museum specimens of extinct populations from neighboring islands. For comparison, their less endangered (= more abundant) sister taxa, the Luzon Tarictic Hornbill (P. manillae) from the Luzon and Polillo Islands and the Writhed Hornbill (A. leucocephalus) from Mindanao Island, were also included in the study. We reconstructed the population history of the two Penelopides species and assessed the genetic population structure of the remaining wild populations in all four species. Results: Mitochondrial and nuclear data concordantly show a clear genetic separation according to the island of origin in both Penelopides species, but also unravel sporadic over-water movements between islands. We found evidence that deforestation in the last century influenced these migratory events. Both classes of markers and the comparison to museum specimens reveal a genetic diversity loss in both Visayan hornbill species, P. panini and A. waldeni, as compared to their more abundant relatives. This might have been caused by local extinction of genetically differentiated populations together with the dramatic decline in the abundance of the extant populations. Conclusions: We demonstrated a loss in genetic diversity of P. panini and A. waldeni as compared to their sister taxa P. manillae and A. leucocephalus. Because of the low potential for gene flow and population exchange across islands, saving of the remaining birds of almost extinct local populations - be it in the wild or in captivity - is particularly important to preserve the species' genetic potential. KW - Biogeography KW - Bucerotidae KW - Conservation genetics KW - Genetic diversity loss KW - Microsatellites KW - Mitochondrial control region I KW - Philippine archipelago KW - Phylogeography Y1 - 2012 U6 - https://doi.org/10.1186/1471-2148-12-203 SN - 1471-2148 VL - 12 IS - 25 PB - BioMed Central CY - London ER - TY - GEN A1 - Sammler, Svenja A1 - Ketmaier, Valerio A1 - Havenstein, Katja A1 - Krause, Ulrike A1 - Curio, Eberhard A1 - Tiedemann, Ralph T1 - Mitochondrial control region I and microsatellite analyses of endangered Philippine hornbill species (Aves; Bucerotidae) detect gene flow between island populations and genetic diversity loss N2 - Background: The Visayan Tarictic Hornbill (Penelopides panini) and the Walden's Hornbill (Aceros waldeni) are two threatened hornbill species endemic to the western islands of the Visayas that constitute - between Luzon and Mindanao - the central island group of the Philippine archipelago. In order to evaluate their genetic diversity and to support efforts towards their conservation, we analyzed genetic variation in similar to 600 base pairs (bp) of the mitochondrial control region I and at 12-19 nuclear microsatellite loci. The sampling covered extant populations, still occurring only on two islands (P. panini: Panay and Negros, A. waldeni: only Panay), and it was augmented with museum specimens of extinct populations from neighboring islands. For comparison, their less endangered (= more abundant) sister taxa, the Luzon Tarictic Hornbill (P. manillae) from the Luzon and Polillo Islands and the Writhed Hornbill (A. leucocephalus) from Mindanao Island, were also included in the study. We reconstructed the population history of the two Penelopides species and assessed the genetic population structure of the remaining wild populations in all four species. Results: Mitochondrial and nuclear data concordantly show a clear genetic separation according to the island of origin in both Penelopides species, but also unravel sporadic over-water movements between islands. We found evidence that deforestation in the last century influenced these migratory events. Both classes of markers and the comparison to museum specimens reveal a genetic diversity loss in both Visayan hornbill species, P. panini and A. waldeni, as compared to their more abundant relatives. This might have been caused by local extinction of genetically differentiated populations together with the dramatic decline in the abundance of the extant populations. Conclusions: We demonstrated a loss in genetic diversity of P. panini and A. waldeni as compared to their sister taxa P. manillae and A. leucocephalus. Because of the low potential for gene flow and population exchange across islands, saving of the remaining birds of almost extinct local populations - be it in the wild or in captivity - is particularly important to preserve the species' genetic potential. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 378 KW - biogeography KW - bucerotidae KW - conservation genetics KW - genetic diversity loss KW - microsatellites KW - mitochondrial control region I KW - Philippine archipelago KW - phylogeography Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-401108 ER - TY - GEN A1 - Sammler, Svenja A1 - Ketmaier, Valerio A1 - Havenstein, Katja A1 - Tiedemann, Ralph T1 - Intraspecific rearrangement of duplicated mitochondrial control regions in the luzon tarictic hornbill penelopides manillae (Aves: Bucerotidae) T2 - Journal of molecular evolution N2 - Philippine hornbills of the genera Aceros and Penelopides (Bucerotidae) are known to possess a large tandemly duplicated fragment in their mitochondrial genome, whose paralogous parts largely evolve in concert. In the present study, we surveyed the two distinguishable duplicated control regions in several individuals of the Luzon Tarictic Hornbill Penelopides manillae, compare their characteristics within and across individuals, and report on an intraspecific mitochondrial gene rearrangement found in one single specimen, i.e., an interchange between the two control regions. To our knowledge, this is the first observation of two distinct mitochondrial genome rearrangements within a bird species. We briefly discuss a possible evolutionary mechanism responsible for this pattern, and highlight potential implications for the application of control region sequences as a marker in population genetics and phylogeography. KW - Bucerotidae KW - Concerted evolution KW - Control region KW - Mitochondrial gene order KW - Mitochondrial recombination KW - Philippine archipelago Y1 - 2013 U6 - https://doi.org/10.1007/s00239-013-9591-y SN - 0022-2844 SN - 1432-1432 VL - 77 IS - 5-6 SP - 199 EP - 205 PB - Springer CY - New York ER - TY - JOUR A1 - Sammler, Svenja A1 - Bleidorn, Christoph A1 - Tiedemann, Ralph T1 - Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae) provide evidence for pervasive mitochondrial DNA recombination JF - BMC genomics N2 - Background: Although nowaday it is broadly accepted that mitochondrial DNA (mtDNA) may undergo recombination, the frequency of such recombination remains controversial. Its estimation is not straightforward, as recombination under homoplasmy (i.e., among identical mt genomes) is likely to be overlooked. In species with tandem duplications of large mtDNA fragments the detection of recombination can be facilitated, as it can lead to gene conversion among duplicates. Although the mechanisms for concerted evolution in mtDNA are not fully understood yet, recombination rates have been estimated from "one per speciation event" down to 850 years or even "during every replication cycle". Results: Here we present the first complete mt genome of the avian family Bucerotidae, i.e., that of two Philippine hornbills, Aceros waldeni and Penelopides panini. The mt genomes are characterized by a tandemly duplicated region encompassing part of cytochrome b, 3 tRNAs, NADH6, and the control region. The duplicated fragments are identical to each other except for a short section in domain I and for the length of repeat motifs in domain III of the control region. Due to the heteroplasmy with regard to the number of these repeat motifs, there is some size variation in both genomes; with around 21,657 bp (A. waldeni) and 22,737 bp (P. panini), they significantly exceed the hitherto longest known avian mt genomes, that of the albatrosses. We discovered concerted evolution between the duplicated fragments within individuals. The existence of differences between individuals in coding genes as well as in the control region, which are maintained between duplicates, indicates that recombination apparently occurs frequently, i. e., in every generation. Conclusions: The homogenised duplicates are interspersed by a short fragment which shows no sign of recombination. We hypothesize that this region corresponds to the so-called Replication Fork Barrier (RFB), which has been described from the chicken mitochondrial genome. As this RFB is supposed to halt replication, it offers a potential mechanistic explanation for frequent recombination in mitochondrial genomes. Y1 - 2011 U6 - https://doi.org/10.1186/1471-2164-12-35 SN - 1471-2164 VL - 12 IS - 2 PB - BioMed Central CY - London ER - TY - GEN A1 - Sammler, Svenja A1 - Bleidorn, Christoph A1 - Tiedemann, Ralph T1 - Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae) provide evidence for pervasive mitochondrial DNA recombination N2 - Background: Although nowaday it is broadly accepted that mitochondrial DNA (mtDNA) may undergo recombination, the frequency of such recombination remains controversial. Its estimation is not straightforward, as recombination under homoplasmy (i.e., among identical mt genomes) is likely to be overlooked. In species with tandem duplications of large mtDNA fragments the detection of recombination can be facilitated, as it can lead to gene conversion among duplicates. Although the mechanisms for concerted evolution in mtDNA are not fully understood yet, recombination rates have been estimated from "one per speciation event" down to 850 years or even "during every replication cycle". Results: Here we present the first complete mt genome of the avian family Bucerotidae, i.e., that of two Philippine hornbills, Aceros waldeni and Penelopides panini. The mt genomes are characterized by a tandemly duplicated region encompassing part of cytochrome b, 3 tRNAs, NADH6, and the control region. The duplicated fragments are identical to each other except for a short section in domain I and for the length of repeat motifs in domain III of the control region. Due to the heteroplasmy with regard to the number of these repeat motifs, there is some size variation in both genomes; with around 21,657 bp (A. waldeni) and 22,737 bp (P. panini), they significantly exceed the hitherto longest known avian mt genomes, that of the albatrosses. We discovered concerted evolution between the duplicated fragments within individuals. The existence of differences between individuals in coding genes as well as in the control region, which are maintained between duplicates, indicates that recombination apparently occurs frequently, i. e., in every generation. Conclusions: The homogenised duplicates are interspersed by a short fragment which shows no sign of recombination. We hypothesize that this region corresponds to the so-called Replication Fork Barrier (RFB), which has been described from the chicken mitochondrial genome. As this RFB is supposed to halt replication, it offers a potential mechanistic explanation for frequent recombination in mitochondrial genomes. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 367 KW - d-loop region KW - concerted evolution KW - gene order KW - birds KW - phylogeny KW - heteroplasmy KW - organization KW - duplication KW - vertebrates KW - alignment Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400889 ER - TY - JOUR A1 - Sammler, Svenja A1 - Havenstein, Katja A1 - Tiedemann, Ralph T1 - Fourteen new microsatellite markers for the Visayan tarictic hornbill (Penelopides panini) and their cross-species applicability among other endangered Philippine hornbills JF - Conservation genetics resources N2 - Fourteen microsatellite markers were isolated and characterized for the endangered Visayan tarictic hornbill (Penelopides panini, Aves: Bucerotidae). In an analysis of 76 individuals, the number of alleles per locus varied from one to 12. Expected and observed heterozygosity ranged from 0.00 to 0.87 and from 0.00 to 0.89, respectively. All primers also amplify microsatellite loci in Luzon tarictic hornbill (Penelopides manillae), Mindanao tarictic hornbill (Penelopides affinis), the critically endangered Walden's hornbill (Aceros waldeni) and the near-threatened writhed hornbill (Aceros leucocephalus). Two loci which are monomorphic in P. panini were found polymorphic in at least one of the other species. These 14 new microsatellite markers specifically developed for two genera of Philippine hornbills, in combination with those already available for the hornbill genera Buceros and Bucorvus, comprise a reasonable number of loci to genetically analyse wild and captive populations of these and probably other related, often endangered hornbills. KW - Aceros KW - Bucerotidae KW - Cross-species amplification KW - Microsatellites KW - Penelopides Philippine hornbills Y1 - 2012 U6 - https://doi.org/10.1007/s12686-011-9567-4 SN - 1877-7252 VL - 4 IS - 2 SP - 435 EP - 438 PB - Springer CY - Dordrecht ER -