Male aggression in the banded demoiselle damselfly Calopteryx splendens
Popular science summary As the climate warms and species move northwards, some species encounter populations of a similar species. In this case, the banded demoiselle damselfly Calopteryx splendens is moving north, further into Fennoscandia than it has been known to go before, and is meeting populations of the beautiful demoiselle damselfly Calopteryx virgo. Males of both species set up and defen