1001 Arabian NewtsPosted on 03-07-2017 by Hilde Pracht
Coverphoto: Ommatotriton ophryticus - banded newt
With their beautifully coloured and patterned skins, banded newts (genus Ommatotriton) have a mesmerizing appearance. These fascinating amphibians live in the Near East, where they are widely distributed. Unfortunately, biogeographic studies in this Near East region are still underrepresented in the literature. For banded newts specifically, a range wide study was still lacking.
Luckily, Naturalis researchers brought about change. To improve our knowledge of Near Eastern biogeography, they carried out an extensive research, using the banded newts as a case study. They dove into the genetic background and species distribution of the banded newts. The goal was to find out how many different species the genus included and to unravel the phylogenetic relationships between them. DNA-research and fossils were used to investigate the ages of and relationships between species and finally to create species distribution models.
Photo: Ommatotriton nesterovi, one of the three banded newt species
The researchers confirmed the presence of three different banded newt species. Their last common ancestor was dated way back in time: 25 million years ago! Yet, it was also found that the diversification into three species took place over a very short time span.
This story about the rich biodiversity of banded newts is comparable with the histories of origin of other animals and plants in the region. The researchers suggest two causes for this phenomenon. First of all, turbulent plate tectonics in the region increased speciation. By creating mountains and sea straights, flora and fauna got spatially separated, causing new species to rise. Next, all those different species could continue to exist, because in the Near East the climate stayed relatively stable during the Pleistocene Ice Ages. In other regions, the Ice Ages caused many species to go extinct.
The banded newt case solidifies the important role the Near East plays in generating and sustaining biodiversity. With its unique biogeographic history, this region provides many interesting systems to study the evolution of species.
Want to learn more? The paper is freely available at: http://www.sciencedirect.com/science/article/pii/S1055790317304086
Photo: overview of the three different species of banded newts.