Complex sentence: They concluded that Indigobirds switch their song between several different hosts, but, the switching does not conclude that the species are biologically different but in fact, they are very much related to one another in which they are not isolated from other species (3).
Split into simpler sentences: They concluded that indigobirds switch songs among several different hosts, but that this switching does not mean that the species are biologically different. In fact, they are very much related to one another in which they are not isolated from other species (3).