Rike Stelkens

Wallenberg Academy Fellow 2017

Natural Sciences

Dr. Rike Stelkens
Stockholm University

Nominated by
Stockholm University

Does evolution move faster thanks to hybrids?

We live in a world where the pace of environmental change poses serious threats to biodiversity. To avoid extinction when environments deteriorate, populations must evolve. Wallenberg Academy Fellow Rike Stelkens will investigate how hybridization – when different species or populations exchange genes – can help the evolution of new adaptations, and allow populations to survive in new or stressful environment.

When two species interbreed, their hybrid progeny is often sterile and less likely to survive because the genomes from distantly related species are rarely compatible. However, in some cases hybrids are viable and some of them even have extreme phenotypes that may or may not be beneficial when facing new environmental challenges. Researchers call these hopeful monsters because they may survive and thrive in new ecological niches. Sometimes an entirely new species emerges through hybridization.

Wallenberg Academy Fellow Rike Stelkens at the Department of Zoology, Stockholm University, will investigate how hybridization increases genetic diversity, and how this may protect populations from extinction in a changing world.

She uses the fast and flexible model system Baker’s yeast to observe evolution in her laboratory over hundreds of generations in a few weeks time – an approach called experimental evolution. She will take populations of yeast and evolve them in different environments for many hundreds of generations so they adapt to new conditions. Then she will generate hybrids between these lineages and expose them to novel and stressful environments. Over the course of these evolution experiments, she will sequence the genomes of hybrid and parent populations to investigate whether the genetic diversity that results from hybridization helps yeast to survive in these new environments.

Photo: Marcus Marcetic