@misc{KiemelGurkeParaskevopoulouetal.2022, author = {Kiemel, Katrin and Gurke, Marie and Paraskevopoulou, Sofia and Havenstein, Katja and Weithoff, Guntram and Tiedemann, Ralph}, title = {Variation in heat shock protein 40 kDa relates to divergence in thermotolerance among cryptic rotifer species}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1305}, issn = {1866-8372}, doi = {10.25932/publishup-57863}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-578635}, pages = {14}, year = {2022}, abstract = {Genetic divergence and the frequency of hybridization are central for defining species delimitations, especially among cryptic species where morphological differences are merely absent. Rotifers are known for their high cryptic diversity and therefore are ideal model organisms to investigate such patterns. Here, we used the recently resolved Brachionus calyciflorus species complex to investigate whether previously observed between species differences in thermotolerance and gene expression are also reflected in their genomic footprint. We identified a Heat Shock Protein gene (HSP 40 kDa) which exhibits cross species pronounced sequence variation. This gene exhibits species-specific fixed sites, alleles, and sites putatively under positive selection. These sites are located in protein binding regions involved in chaperoning and may therefore reflect adaptive diversification. By comparing three genetic markers (ITS, COI, HSP 40 kDa), we revealed hybridization events between the cryptic species. The low frequency of introgressive haplotypes/alleles suggest a tight, but not fully impermeable boundary between the cryptic species.}, language = {en} } @misc{SpikesRodriguezSilvaBennettetal.2021, author = {Spikes, Montrai and Rodr{\´i}guez-Silva, Rodet and Bennett, Kerri-Ann and Br{\"a}ger, Stefan and Josaphat, James and Torres-Pineda, Patricia and Ernst, Anja and Havenstein, Katja and Schlupp, Ingo and Tiedemann, Ralph}, title = {A phylogeny of the genus Limia (Teleostei: Poeciliidae) suggests a single-lake radiation nested in a Caribbean-wide allopatric speciation scenario}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1866-8372}, doi = {10.25932/publishup-54888}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-548882}, pages = {1 -- 8}, year = {2021}, abstract = {Objective The Caribbean is an important global biodiversity hotspot. Adaptive radiations there lead to many speciation events within a limited period and hence are particularly prominent biodiversity generators. A prime example are freshwater fish of the genus Limia, endemic to the Greater Antilles. Within Hispaniola, nine species have been described from a single isolated site, Lake Mirago{\^a}ne, pointing towards extraordinary sympatric speciation. This study examines the evolutionary history of the Limia species in Lake Mirago{\^a}ne, relative to their congeners throughout the Caribbean. Results For 12 Limia species, we obtained almost complete sequences of the mitochondrial cytochrome b gene, a well-established marker for lower-level taxonomic relationships. We included sequences of six further Limia species from GenBank (total N  = 18 species). Our phylogenies are in concordance with other published phylogenies of Limia. There is strong support that the species found in Lake Mirago{\^a}ne in Haiti are monophyletic, confirming a recent local radiation. Within Lake Mirago{\^a}ne, speciation is likely extremely recent, leading to incomplete lineage sorting in the mtDNA. Future studies using multiple unlinked genetic markers are needed to disentangle the relationships within the Lake Mirago{\^a}ne clade.}, language = {en} } @misc{SenczukHavensteinMilanaetal.2018, author = {Senczuk, Gabriele and Havenstein, Katja and Milana, Valentina and Ripa, Chiara and De Simone, Emanuela and Tiedemann, Ralph and Castiglia, Riccardo}, title = {Spotlight on islands}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {991}, issn = {1866-8372}, doi = {10.25932/publishup-44636}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-446360}, pages = {14}, year = {2018}, abstract = {Groups of proximate continental islands may conceal more tangled phylogeographic patterns than oceanic archipelagos as a consequence of repeated sea level changes, which allow populations to experience gene flow during periods of low sea level stands and isolation by vicariant mechanisms during periods of high sea level stands. Here, we describe for the first time an ancient and diverging lineage of the Italian wall lizard Podarcis siculus from the western Pontine Islands. We used nuclear and mitochondrial DNA sequences of 156 individuals with the aim of unraveling their phylogenetic position, while microsatellite loci were used to test several a priori insular biogeographic models of migration with empirical data. Our results suggest that the western Pontine populations colonized the islands early during their Pliocene volcanic formation, while populations from the eastern Pontine Islands seem to have been introduced recently. The inter-island genetic makeup indicates an important role of historical migration, probably due to glacial land bridges connecting islands followed by a recent vicariant mechanism of isolation. Moreover, the most supported migration model predicted higher gene flow among islands which are geographically arranged in parallel. Considering the threatened status of small insular endemic populations, we suggest this new evolutionarily independent unit be given priority in conservation efforts.}, language = {en} } @misc{SammlerKetmaierHavensteinetal.2017, author = {Sammler, Svenja and Ketmaier, Valerio and Havenstein, Katja and Krause, Ulrike and Curio, Eberhard and Tiedemann, Ralph}, title = {Mitochondrial control region I and microsatellite analyses of endangered Philippine hornbill species (Aves; Bucerotidae) detect gene flow between island populations and genetic diversity loss}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-401108}, pages = {14}, year = {2017}, abstract = {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.}, language = {en} }