Author Archives: Ben Wielstra

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 →

The first crested newt I ever saw was in Meijendel, a dune area close to Leiden (where I studied biology at the time). This crested newt population is odd because it is completely isolated from the main distribution range. Could … Continue reading →

Adult marbled and crested newts have two versions – a long and a short one – of their largest chromosome: chromosome 1. They randomly transmit either the long or the short version to each of their sex cells, resulting in … Continue reading →

Phylogeography – the study of the geographical genetic structure within species or groups of closely related species – was until recently typically based on one or a few genes. Nowadays, many genes can be consulted. This allows us to better … Continue reading →

In a big chunk of France, the crested newt Triturus cristatus and the marbled newt T. marmoratus live alongside one another. Sometimes things get frisky: about one in 25 adult Triturus newts here is a first generation (F1) hybrid between … Continue reading →

This spring we conducted fieldwork in the Dutch dune area Meijendel, close to Leiden. One of our target species was the northern crested newt (Triturus cristatus). There is a crested newt population in Meijendel that is completely isolated from the … Continue reading →

In an article aimed at high school students for the journal Frontiers for Young Minds we introduce the evolutionary mystery posed by balanced lethal systems. We use crested newts as an example throughout. Please have a look here. Reference: Meilink, … Continue reading →

I have been awarded an ENW-M-1 grant in NWO’s Open Competition ENW. With this project I will expand my research line on the balanced lethal system in Triturus newts. We know that only those Triturus offspring that possess two different … Continue reading →

In the 1970s Jozef F. Schmidtler noticed that crested newts in the Berchtesgadener Land, in the extreme southeast of Germany, show morphological characteristics of the Italian crested newt (Triturus carnifex). A particular striking feature was the bright yellow stripe along … Continue reading →