denmark and sweden but they haven't conquered the majority of the baltic and. if we can show that the southern spaces has a different genetic repertoire and can cope with the lowest salt content then at the sudden once transferred north that could be a threat on the other hand we don't know what would happen if the southern and northern jellies were brought together we could get super potent hybrids or we could get hybrids that can't reproduce it's a very exciting question that's really significant for the future of the baltic. the scientist is bringing 40 come jellies from america the black sea and the baltic together in the lab. over the next few years she'll carry out an evolutionary and breeding experiments funded by the use marie curie program and the danish council for independent research for natural sciences. the plankton