Hybrid newts movePosted on 10-05-2017 by Ben Wielstra, Hilde Pracht
Naturalis Researcher Ben Wielstra studied hybrid zone movement in Turkey.
The process of speciation often involves a stage in which the two diverging species can still produce fertile offspring together. So, when these two species meet and breed, they hybridize and exchange genes. The region in which this happens, is called a hybrid zone. When one of the two hybridizing species is more fit and replaces the other, this hybrid zone would move across the landscape, following the road of conquest of the dominant species.
Hybrid zone movement leaves traces in the genes of the animals. The receding species that is being replaced leaves behind a trail of genes within the advancing species. Studying this genetic footprint, therefore provides clues about the movement of the hybrid zone across time and space. Common thought has been that moving hybrid zones quickly stabilize and come to a halt at barriers of unsuitable habitat. Despite a suspicion that hybrid zones could potentially travel further and longer, so far evidence was lacking.
Photo: a hybrid crested newt
This was until researcher Ben Wielstra from Naturalis brought about change. With his team, he studied a hybrid zone between two crested newt species in Turkey. The team sampled the genes of many newts from a lot of localities throughout the range of both species. A trail of genes of one species, left behind in the other, supports the idea that hybrid zone movement can occur over a longer time and space than previously assumed! This means that hybrid zones are probably much more mobile than we previously thought.
In this way, genes can tell us about the distribution of species in the past. And the past, in its turn, can help us understand the future. “Because of the current climate change, some species are forced to shift their habitat”, explains Ben. “Hereby, Species A could replace Species B, when the circumstances for Species A become more favourable. By studying their genes, we learn more about how this boundary between the two species behaved in the past. In this way, we get more insight in how species displacement works. And this knowledge is very useful when we want to predict what the consequences of species displacement in the future will be.”
Do you want to read the whole paper, see http://onlinelibrary.wiley.com/doi/10.1002/evl3.9/full