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Biological invasions in the Anthropocene: Patterns, processes and hidden invasions in an alien amphibian model

<p>Biological invasions are a major challenge for natural systems in the Anthropocene, yet their underlying dynamics often remain insufficiently understood. This project establishes Johnstone’s Whistling Frog (Eleutherodactylus johnstonei) as a new alien amphibian model and reevaluates long-held assumptions about invasion processes and patterns. Native to a small Lesser Antillean island, E. johnstonei has achieved an unexpectedly broad exotic distribution. By integrating ecological, genetic, and microbiome perspectives, this work reveals that the species’ invasion success is driven less by intrinsic biological superiority and more by its compatibility with human-dominated environments.Field surveys conducted 25 years after the frog’s introduction to Colombia demonstrate that its distribution remains tightly associated with urban habitats and their characteristic environmental conditions. Comparative genetic analyses across E. johnstonei, its successful alien congener E. antillensis, and the island endemic E. portoricensis show consistently low genetic diversity in both native and exotic populations, indicating that genetic impoverishment does not preclude invasion success. Instead, species distribution models highlight human footprint as a key predictor of the frog’s wide exotic range. Furthermore, microbiome analyses reveal distinct microbial communities between native and introduced populations, suggesting that microbial restructuring accompanies range expansion and may reflect underlying adaptive or transfer processes.Together, these findings challenge conventional invasion theory by illustrating that islands can act as sources instead of sinks and that species with low genetic diversity can thrive across continents when human-mediated disturbances create favorable conditions. The study argues that conservation strategies should prioritize protecting native habitats over targeting adaptable alien species that succeed largely because of anthropogenic change. More broadly, it calls for a rethinking of "nativeness" in an era of rapid environmental transformation and underscores that the resilience of both macro- and micro-communities - rather than species origin - will shape biodiversity outcomes in the Anthropocene.</p>

ZFMK Herpetology collection

Currently, the herpetological collection houses more than 100,000 catalogued specimens. Amphibians and reptiles are traditionally combined in the collection, with the latter making up nearly two thirds of the total specimens. The collection includes type specimens of around 650 taxa, among them more than 300 primary types (i.e. holotypes, lectotypes, and neotypes) and 100 syntypes that objectively define a scientific name and are literally irreplaceable. The majority of specimens is wet material preserved in ethanol, but the collection also includes osteological specimens and (sub-)fossils. These figures make the herpetological collection at the Leibniz Institute for the Analysis of Biodiversity Change (LIB) - Museum Koenig Bonn one of the largest of its kind in Germany and also one of international importance. Correspondingly to their high species diversity, frogs and squamates (lizards and snakes) represent the majority of species. However, members of all major groups of amphibians (salamanders and caecilians) and reptiles (crocodiles, turtles, and tuataras) are found in the collection. There is no explicit geographic focus and specimens are originating not only from Europe, but from more than 200 countries worldwide. Due to the research focus of past curators and students, the at the Leibniz Institute for the Analysis of Biodiversity Change (LIB) - Museum Koenig Bonn holds remarkable collections from the Mediterranean, the Middle East, Africa, Madagascar, and Brazil. Recent geographical focuses are Southeast Asia, Peru, and the western Palearctic.

Understanding current patterns of diversity and distribution: How and when did Himalayan faunal elements evolve?

The uplift of the Himalaya-Tibet Orogen (HTO) has significantly influenced the global climate and due to its massive elevations and river incisions it likely played an important role as a speciation pump. However, our understanding of the historical biogeography of species in the HTO is far from being comprehensive, as are details of the spatiotemporal evolution of its uplift. The Himalaya plays a key role in elucidating these processes. Results from the applicant's preliminary work, based on molecular data from amphibians, provide initial indications for a Paleo-Tibetan origin of Himalayan faunal components, challenging the long-held belief of immigration from China-Indochina into the Himalaya. Yet, a comprehensive phylogeographic approach is needed, requiring a systematic sampling from biogeographically important regions and an extended analytical framework to pinpoint patterns of diversification in the Himalaya and adjacent regions and to uncover the relative contribution of in-situ speciation versus colonisation in the HTO. Within the project, the applicant will use four carefully chosen terrestrial model systems (spiny frogs, lazy toads, the Himalayan toad and ground skinks), that are sufficiently phylogenetically old and cover a range of different dispersal abilities and ecological preferences. Using cutting-edge targeted exon capture technology in combination with next generation DNA sequencing and state of the art phylogenetic analysis alternative phylogeographic hypotheses will be tested (immigration, vicariance, out-of-Tibet, Paleo-Tibetan origin) and estimate divergence times. The applicant pursues the following objectives with the study: i) Detailed phylogenetic inventory in areas along the southern slope of the Himalaya and surrounding mountain areas; ii) Reconstructing diversification/colonisation pattern; iii) Providing biological evidences for the time of (primary) uplifts of HTO components. Access to museum samples at the applicant's collaboration partners disposal includes almost all relevant species, guaranteeing fast progress of this project. Data amount and resulting statistical power will allow drawing conclusions in an unprecedented power on colonization history and uplift of the HTO. It will also allow identifying factors important for species diversification and contribute to an understanding of the Tertiary environmental conditions of the HTO.

Media and additional measurements belonging to the description of Cophyla fortuna (Microhylidae, Cophylinae)

We describe a new species of arboreal microhylid frog from northern Madagascar. The new species is assigned to the genus Cophyla based on molecular phylogeny and morphological similarities to other species of this genus. Molecular phylogenetic analysis resolved Cophyla fortuna sp. nov. as closely related to C. noromalalae, However, the two species were reciprocally monophyletic both in a tree reconstructed from a combination of mitochondrial genes, and in a tree based on the nuclear RAG-1 gene. The new species, previously identified as candidate species Cophyla sp. Ca4, occurs in lowland bamboo forests around the Marojejy Massif in northeastern Madagascar. It differs from the allopatric C. noromalalae, so far only known from the Montagne d'Ambre Massif in northern Madagascar, by slightly smaller body size and shorter duration and higher spectral frequency of advertisement calls. Several additional genetically divergent mitochondrial lineages of Cophyla, related to the C. fortuna/noromalalae complex and to C. phyllodactyla, occur in intervening areas between Montagne d'Ambre and Marojejy, and their status requires further study. These data are used in the article "Description of the lucky Cophyla (Microhylidae, Cophylinae), a new arboreal frog from Marojejy National Park in north-eastern Madagascar" (https://doi.org/10.11646/zootaxa.4651.2.4).

Anpassungen von Tieren semiarider Gebiete (speziell: Wuestenassel Hemilepistus reaumurt, Riedfrosch Hyperolius viridiflavus) an ihre Umweltbedingungen

Besondere Anpassungen der Wuestenassel Hemilepistus reaumuri sind ihr Sozialverhalten im Familienverband und extreme Orientierungsleistungen, mit deren Hilfe sie ihre Hoehle wiederfindet. Beide Verhaltenskomplexe wurden und werden untersucht. Der Riedfrosch Hyperolius viridiflavus vermag in der Trockenzeit mehrere Monate in der Vegetationsschicht semiarider Gebiete ohne Nahrungsaufnahme zu ueberstehen. In diesem Zusammenhang werden die Art des Verdunstungsschutzes und besondere Anpassungen beim Atmungsstoffwechsel untersucht.

Die Wirkung simulierter Schwerelosigkeit und Ueberschwere im Zellbereich der Organismen

Reaktionen verschiedener Zellsysteme auf Schwerelosigkeitssimulation und erhoehte Beschleunigung werden im Zusammenhang mit der Frage zellphysiologischer Risiken fuer den Raumfahrer untersucht; gewebskundliche Untersuchung des Gleichgewichtsorgans von Froschembryonen und -larven zur Bewertung der Gefahr einer degenerativen Entartung dieses Organs beim Raumfahrer.

Ressortforschungsplan 2020^Wildkatzenwälder von morgen, Teilvorhaben: Wildkatzenwälder für Sachsen

Ressortforschungsplan 2020^Wildkatzenwälder von morgen, Teilvorhaben: Wildkatzenwälder für Nordrhein-Westfalen

Die Gattung (Eleutherodactylus) auf dem Guaiquinima-Tafelberg, Venezuela

Herpetologie: Systematisch-taxonomische Untersuchungen Froschlurchen des venezolanischen Guaiquinima-Tafelberges - Vor allem Neubeschreibungen von Arten der Gattung 'Eleutherodactylus'

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