Sebastian Steinfartz

Leipzig University · Institute of Biology

Recognizing the influence of pathogen diversity on infection dynamics is crucial for mitigating emerging infectious diseases. Characterising such diversity is often complex, for instance when multiple pathogen variants exist that interact differently with the environment and host. Here, we explore genotypic and phenotypic variation of Batrachochytr...

Global change is impacting biodiversity across all habitats on earth. New selection pressures from changing climatic conditions and other anthropogenic activities are creating heterogeneous ecological and evolutionary responses across many species' geographic ranges. Yet we currently lack standardised and reproducible tools to effectively predict t...

Anthropogenic habitat modification and climate change are fundamental drivers of biodiversity declines, reducing the evolutionary potential of species, particularly at their distributional limits. Supportive breeding or reintroductions of individuals are often made to replenish declining populations, sometimes informed by genetic analysis. However,...

Traditional methods of phylogenetic reconstruction and species delimitation may be impeded by frequent hybridization among lineages. In this study, we conducted phylogenetic and clustering analyses of ddRAD genomic data on the entire genus Salamandra, which includes six species and over 25 subspecies of terrestrial salamanders. We expanded previous...

For many species, population sizes are unknown despite their importance for conservation. For population size estimation, capture-mark-recapture (CMR) studies are often used, which include the necessity to identify each individual, mostly through individual markings or genetic characters. Invasive marking techniques, however, can negatively affect...

The Salamander plague: Characterization, current situation in Germany, recommendations for action The pathogen Batrachochytrium salamandrivorans (Bsal), one of the two amphibian chytrid fungi and the cause of the salamander plague, was introduced to Europe from Asia. Currently , Bsal outbreaks are known in the wild from > 130 sites in Belgium, Ge...

Population surveys are vital for wildlife management, yet traditional methods often demand excessive time and resources, leading to data gaps for many species. Modern technologies such as drones can facilitate field surveys but may also increase data analysis challenges. Citizen Science (CS) can address this issue by engaging non-specialists for da...

Understanding wildlife responses to novel threats is vital in counteracting biodiversity loss. The emerging pathogen Batrachochytrium salamandrivorans (Bsal) causes dramatic declines in European salamander populations, and is considered an imminent threat to global amphibian biodiversity. However, real-life disease outcomes remain largely uncharact...

Striking colour patterns of animals have fascinated humans for centuries. Given the obviousness of colouration, this trait proves promising when studying drivers of diversification on the species-, population-, and individual level (Cuthill et al. 2017; Endler and Mappes 2017; Briolat et al. 2019). Additonally, colouration of animals is among the m...

Anthropogenically induced habitat modification and climate change are fundamental drivers of biodiversity declines, reducing the evolutionary potential of species populations, particularly at the limits of their distribution ranges. Supportive breeding or reintroductions of individuals are often made to replenish declining populations, sometimes in...

1. Global change is impacting biodiversity across all habitats on earth. New selection pressures from changing climatic conditions and other anthropogenic activities are creating heterogeneous ecological and evolutionary responses across many species' geographic ranges. Yet we currently lack standardised and reproducible tools to effectively predic...

Context Habitat connectivity can stabilise animal populations by facilitating immigration and genetic exchange, but it increases the risk of infectious diseases being spread by hosts. Chytridiomycosis caused by Batrachochytrium salamandrivorans (Bsal) threatens European salamander diversity. The extent to which the connectivity of populations of fi...

Background Large-scale species monitoring remains a significant conservation challenge. Given the ongoing biodiversity crisis, the need for reliable and efficient methods has never been greater. Drone-based techniques have much to offer in this regard: they allow access to otherwise unreachable areas and enable the rapid collection of non-invasive...

The composition of cutaneous (skin-associated) bacterial communities of amphibians has been intensively studied in light of the potential of some of these commensal bacterial taxa to mitigate infection with the chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal). However, surprisingly, the absolute densities in which th...

Galápagos marine iguanas are primarily associated with the marine environment and show special nutritional adaptations. They are the only lizards worldwide that forage on marine macroalgae. Until now, consumed algae have been identified by direct observations during their feeding activities and microscopic identification in faeces samples. In this...

Dispersal is a central process in ecology and evolution with far reaching consequences for the dynamics and genetics of spatially structured populations (SSPs). Individuals can adjust their decisions to disperse according to local fitness prospects, resulting in context-dependent dispersal. By determining dispersal rate, distance and direction , th...

Starting in 2010, rapid fire salamander (Salamandra salamandra) population declines in northwestern Europe heralded the emergence of Batrachochytrium salamandrivorans (Bsal), a salamander‐pathogenic chytrid fungus. Bsal poses an imminent threat to global salamander diversity owing to its wide host range, high pathogenicity, and long‐term persistenc...

Gut microorganisms are crucial for many biological functions playing a pivotal role in the host’s well-being. We studied gut bacterial community structure of marine iguana populations across the Galápagos archipelago. Marine iguanas depend heavily on their specialized gut microbiome for the digestion of dietary algae, a resource whose growth was st...

The Near Eastern fire salamander (Salamandra infraimmaculata) reaches its southern distribution range in Israel. Although the population structure has been analysed in central Israel and at the southern distribution limit, we lack knowledge on populations in the northern area, such as along Mount Hermon. S. infraimmaculata occurs at Mt. Hermon alon...

The salamander genus Salamandra is widespread across Europe, North Africa, and the Near East and is renowned for its conspicuous and polymorphic colouration and diversity of reproductive modes. The phylogenetic relationships within the genus, and especially among the highly polymorphic species S. salamandra, have been very challenging to elucidate,...

Hybridization can leave genealogical signatures in an organism's genome, originating from the parental lineages and persisting over time. This potentially confounds phylogenetic inference methods that aim to represent evolution as a strictly bifurcating tree. We apply a phylotranscriptomic approach to study the evolutionary history of, and test for...

The chytrid fungus Batrachochytrium salamandrivorans (Bsal), recently introduced from Asia to Europe, causes mortality in numerous species of salamanders and newts and has led to catastrophic declines and local extinctions of the European fire salamander (Salamandra salamandra) in the Netherlands, Belgium, and Germany. Due to the continuous spread...

The salamander plague, caused by the amphibian chytrid fungus Batrachochytrium salamandrivorans (Bsal), is one of the most devastating amphibian diseases, currently threatening the entire Western Palearctic caudate diversity with extinction. Apparently of Asian origin and recently introduced into Europe, Bsal is known from currently ca. 80 sites in...

Emerging infectious diseases are one of the main suggested reasons for global amphibian decline. Fungal agents play a key role. Since its introduction, the Asian pathogen Batrachochytrium salamandrivorans has driven the Europe-an fire salamander, Salamandra salamandra, to the edge of extinction in the Netherlands and caused severe population declin...

Communication between individuals via molecules, termed chemosignaling, is widespread among animal and plant species. However, we lack knowledge on the specific functions of the substances involved for most systems. The femoral gland is an organ that secretes a waxy substance involved in chemical communication in lizards. While the lipids and volat...

In the original article, there was a mistake in Figure 5 as published. When summarizing the results in the scheme, the treatment groups were mixed, and so some of the symbols for morphological and gene expression traits were not in accordance with the results [...]

Warning colouration reduces predation risk by signalling or mimicking the unpleasantness of prey and therefore increases survival. We tested in two experiments the evolutionary costs and benefits of the yellow colour pattern in fire salamanders (Salamandra salamandra), which display a yellow/black colour pattern usually associated with toxic alkalo...

Colouration has been associated with multiple biologically relevant traits that drive adaptation and diversification in many taxa. However, despite the great diversity of colour patterns present in amphibians the underlying molecular basis is largely unknown. Here, we leverage insight from a highly colour‐variable lineage of the European fire salam...

see the conference paper of the same name

Seit 2008 wurde in den südöstlichen Niederlanden ein dramatischer Einbruch der Feuersalamanderpopulation beobachtet. 2013 wurde mit der Beschreibung des Krankheitserregers die Ursache erkannt. Batrachochytrium salamandrivorans, kurz Bsal, ist ein Amphibien-Hautpilz, der vor allem für Feuersalamander, aber auch für Molche, eine große Gefahr darstell...

Background: Differences in the trophic niche often underlie ecological specialization of individuals and can promote ecological speciation of populations, but studies showing a link between differences in the trophic niche and genetic differentiation of populations are rare. On the island of San Cristóbal (Galapágos archipelago), a strong genetic d...

Amphibians, the most severely declining vertebrate class, are especially threatened by pathogenic chytrid fungi. Batrachochytrium salamandrivorans (Bsal) was most likely introduced from Asia to Europe. Here, it causes mortal skin diseases (chytridiomycosis) and Bsal-caused mass mortalities in fire salamanders (Salamandra salamandra). Individuals of...

Der Erreger der als Salamanderpest bezeichneten Amphibienhauterkrankung - der Chytridpilz Batrachochytrium salamandrivorans - ist inzwischen an mehreren Standorten in Mitteleuropa (in den Niederlanden, Belgien und Deutschland) nachgewiesen, mit besonders schweren Folgen für die anscheinend sensibelste Wirtsart, den Feuersalamander (Salamandra salam...

In this contribution, the aspects of reptile and amphibian speciation that emerged from research performed over the past decade are reviewed. First, this study assesses how patterns and processes of speciation depend on knowing the taxonomy of the group in question, and discuss how integrative taxonomy has contributed to speciation research in thes...

The Green Toad (Bufotes viridis) in Germany is mostly confined to secondary habitats and is experiencing severe population declines especially at its northwestern range boundary in the city of Cologne. As a basis for conservation management of this species, viz. to investigate the status of the population structure, we used a library of over 15,000...

The infectious chytrid fungus Batrachochytrium salamandrivorans ( Bsal ) has been responsible for severe population declines of salamander populations in Europe. Serious population declines and loss of urodelan diversity may occur if appropriate action is not taken to mitigate against the further spread and impact of Bsal . We provide an overview o...

Prey species signalling their toxicity to potential predators via conspicuous coloration occur frequently in nature. This survival strategy, called aposematism, is thought to be successful when based on honest qualitative or quantitative signalling of toxicity and predator learning behaviour. However, evidence supporting these basic assumptions is...

The combination of niche modelling and landscape genetics (genomics) helps to disentangle processes that have shaped population structure in the evolutionary past and presence of species. Herein, we integrate a comprehensive genomic dataset with ecological parameters and niche modelling for the threatened Kaiser’s newt, a newt species adapted to mo...

Immediate and reliable pathogen detection in large numbers of samples is essential in wildlife disease monitoring and is often realized by DNA-based techniques. Pooling samples increases processing efficiency and reduces processing costs, and has been suggested as a viable technique for quantitative PCR detection of fungal amphibian pathogens of th...

We reconstruct the molecular phylogeny of Near Eastern mountain brook newts of the genus Neurergus (family Salamandridae) based on newly determined RADseq data, and compare the outcomes of concatenation-based phylogenetic reconstruction with species-tree inference. Furthermore, we test the current taxonomy of Neurergus (with four species: Neurergus...

„Natur Natur sein lassen“ ist die Idee und das Ziel eines Nationalparks, was die Förderung und den Erhalt des für dieses Gebiet typischen Ökosystems und dessen natürlicher Vielfalt beinhaltet. Dieses Motto gilt insbesondere im Entwicklungs-Nationalpark Harz bislang schon für die Naturdynamikzonen (Kernzonen), welche sich selbst überlassen sind, d.h...

North Africa is a climatically and topographically complex region with unique biotic assemblages resulting from the combination of multiple biogeographic realms. Here, we assess the role of climate in promoting intra-specific diversification in a Palearctic relict, the North African fire salamander, Salamandra algira, using a combination of phyloge...

Infektionskrankheiten werden als eine der Hauptursachen des alarmierenden globalen Rückgangs von Amphibien angesehen. Seit Jahrzehnten verursacht der Amphibien-Hautpilz Batrachochytrium dendrobatidis (Bd) weltweit dramatische Bestandseinbrüche und -verluste, während ein weiterer Amphibien-Hautpilz namens Batrachochytrium salamandrivorans (Bsal) ers...

Speciation processes have long been inferred from phylogenetic, phylogeographic, and biogeographic pattern-driven perspectives. Now much current speciation research is attempting to more directly describe the underlying processes and mechanisms of divergence leading to speciation. Ideally, researchers should integrate both process-and pattern-based...

Terrestrial salamanders of the genus Salamandra represent one of the most prominent groups of amphibians. They are mainly distributed across Europe but also reach Northern Africa and the Near East. Members of the six currently accepted species have long been known to be poisonous; however, work on their toxins was mostly published in German languag...

Escalating occurrences of emerging infectious diseases underscore the importance of understanding microbiome-pathogen interactions. The amphibian cutaneous microbiome is widely studied for its potential to mitigate disease-mediated amphibian declines. Other microbial interactions in this system, however, have been largely neglected in the context o...

In the face of the global biodiversity crisis, the monitoring of species richness and diversity is experiencing an increased demand entailing a raise in cost and time investment. The analysis of species-specific DNA fragments in environmental samples (eDNA) such as from water or soil, facilitate the molecular detection of species without the specif...

One of the most important factors driving amphibian declines worldwide is the infectious disease, chytridiomycosis. Two fungi have been associated with this disease, Batrachochytrium dendrobatidis and B. salamandrivorans (Bsal). The latter has recently driven Salamandra salamandra populations to extirpation in parts of the Netherlands, and Belgium,...

The Pyrenees represent a natural laboratory for biogeographic, evolutionary and ecological research of mountain fauna as a result of the high variety of habitats and the profound effect of the glacial and interglacial periods. There is a paucity of studies providing a detailed insight into genetic processes and better knowledge on the patterns of g...

List and codification of environmental variables from the BIOCLIM dataset. List and codification of environmental variables from the BIOCLIM dataset. Units expressed and mean, median, minimum and maximum values for the 44 Calotriton asper populations. Temperature data is in units °C *10 with a 0.1°C precision. (XLSX)

Pairwise FST values among Calotriton asper populations. Pairwise FST values among Calotriton asper populations. See Table 1 for the population codification; p values were <0.05 for all pairs except for those in bold. (XLSX)

Estimates of effective population size (Ne) for each Calotriton asper population. Estimates of effective population size (Ne) for each Calotriton asper population, calculated with two analytical approaches (ONeSAMP, and COLONY) and using different priors; estimates of the upper and lower 95% CI estimates for each method are indicated. (XLSX)

Plot of deltaK values calculated by Evanno’s method from the Structure analyses. Plot of deltaK values calculated by Evanno’s method from the Structure analyses. A) Global dataset of the 44 Calotriton asper populations. B) Western Pyrenean populations, i.e. Cluster 1. C) Central-eastern Pyrenean populations, i.e. Cluster 2. (TIF)

IBD of the five genetic clusters. Results of the isolation by distance analyses (IBD; Mantel test) of the five genetic Calotriton asper clusters. (XLSX)

Microsatellite data of the Calotriton asper dataset used. (XLSX)

Neighbor-joining tree among the Calotriton asper populations. Neighbor-joining tree using DA distances among the Calotriton asper populations showing the relationships between the five genetic clusters defined by STRUCTURE analysis. As for the population codifications see Table 1. (TIF)

Pearson correlation matrix of environmental and geographical variables. Pearson correlation matrix of environmental and geographical variables. In bold, significant levels of p<0.05. See text, for the codes of the variables. (XLSX)

Univariate linear regression between genetic diversity and geographical and environmental selected variables. Univariate linear regression between genetic diversity and geographical and environmental selected variables of Calotriton asper populations. In bold significant levels of p<0.05. (XLSX)

Linear regressions between the genetic diversity across the longitude and altitude using only stream populations. Linear regressions between the three genetic diversity indices (Ar, HO and HE) across the longitude (A) and altitude (B) ranges when only stream Calotriton asper populations were analyzed. (TIF)

ANOVA among the three distinct habitat types to genetic diversity. ANOVA with Tukey HSD posthoc test among the three distinct habitat types to allelic richness (Ar) observed (HO) and expected heterozygosity (HE). (XLSX)

Spatial interpolation of the genetic diversity measures acroos the Calotriton asper distribution range. Spatial interpolation of the genetic diversity of Calotriton asper. A) First axis of a principal components analysis (PC1) summarizing the allelic richness, the rarified private allele richness and the observed and expected heterozygosities (posi...

Epidemiology relies on understanding the distribution of pathogens which often can be detected through DNA-based techniques, such as quantitative Polymerase Chain Reaction (qPCR). Typically, the DNA of each individual sample is separately extracted and undergoes qPCR analysis. However, when performing field surveys and long-term monitoring, a large...

Transcriptomes of organisms reveal differentiation associated with the use of different habitats. However, this leaves open how much of the observed differentiation can be attributed to genetic differences or to transcriptional plasticity. In this study, we disentangle causes of differential gene expression in larvae of the European fire salamander...