Abstracts (first author)
Can a hybrid outcompete its parental species? - a story about a “super clone“ (Daphnia galeata × longispina hybrid)PDF
The role of hybridization in evolution has been underestimated for a long time. For example, hybrids were often considered less fit then their parental species, due to genetic incompatibility. However, hybridization occurs frequently in plants and in animals. Our recently collected field data showed that a Daphnia community of a small quarry lake in Munich, normally consisting of parental species and hybrids belonging to the D. longispina complex, has become dominated by a single hybrid clone - the “super clone”. By creating artificial communities consisting of the “super clone” and other clones of the D. longispina complex, we proved the competitive strength of the “super clone”. After ~6 generations the “super clone” had increased from 8% to 100% in some of the artificial communities. Additionally, we studied fitness parameters of these clones, kept under two different temperatures. Here, there was no special performance of the “super clone”. Therefore we are currently comparing the carrying capacity of “super clone” with the other clones, by measuring the change in numbers of Daphnia over time, in a certain volume of water. Additionally, we will study fitness parameters of the clones under crowding (and control) conditions. The crowded media will be obtained from crowded stock cultures. We expect the “super clone” to have higher carrying capacity as well as to be less affected by crowded media than the other clones, thereby preventing the other clones from reproducing and establishing within the population. Finding the pattern that makes the “super clone” so special will contribute to a general knowledge about hybrid-specific traits and their contribution to evolutionary processes.