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The awesome banded newt genus comprises three cryptic species that are really old and have little to no genetic exchange between them. However, the ancestral banded newt appears to have radiated into three species in a relatively short time span. … Continue reading →

Understanding how crested and marbled newt embryos develop inside the egg is critical for my research. During this period, body shape is determined, hybrid unfitness would be expected to reveal itself, and half of the embryos are killed by a … Continue reading →

In my lab we are using mtDNA barcoding to try to determine from where within the natural range introduced amphibian populations derive from. In the palmate newt, there is basically no genetic variation north of the Pyrenees Mountains. This also … Continue reading →

A male pygmy marbled newt (left) and a male marbled newt. Pictures by Michael Fahrbach. Although my work is heavily focused on crested newts, there are two marbled newt species in the genus Triturus as well. In a new paper … Continue reading →

In an article aimed at high school students for the journal Frontiers for Young Minds my former student Nienke Prins and I explain hybrid zone movement. Obviously we also mention the best example of hybrid zone movement there is: crested … Continue reading →

In the Dune area of Meijendel, close to Leiden, a population of crested newts occurs. The history of this population is dodgy. While genetic data could not confirm that this population is introduced, the isolated position and apparent rapid expansion … Continue reading →

Three banded newt species are currently recognized. However, this was not always the case. Previously, my lab has shown that these morphologically similar species are genetically super distinct. That is why we suggested their treatment as distinct species – despite … Continue reading →

Befitting its intimidating scientific name, Ichthyosaura, the alpine newt is an interesting beast. The alpine newt is characterized by hugely divergent mtDNA lineages that may well reflect cryptic species (genetically distinct but morphologically similar species). The distribution of these cryptic … Continue reading →

Reference: Wielstra, B., Boer, I. den, France, J., de Visser, M., Struijk, R. (2023). MtDNA barcoding van exotische amfibieën in de duinen. RAVON 89(2): 26-29. Reference: de Visser, M., Prins, N., France, J., Struijk, R., Wielstra, B. (2023). Exotische amfibieën … Continue reading →

The job of immune genes is to fight off pathogens. However, pathogens don’t take this beating lying down. Pathogens adapt to evade the immune genes, forcing the immune genes to counter-adapt in return. To improve your chances against infection in … Continue reading →