This is a really interesting finding, but the conclusions seem a bit arguable. Complexity helps individuals stand out in a crowd, but species markers make it e

This is a really interesting finding, but the conclusions seem a bit arguable. Complexity helps individuals stand out in a crowd, but species markers make it easy to distinguish and find a mate in the first place. So it seems natural to me that declining population would lead to less complexity (due to less competition) and more reliance on the species markers (to help connect more disperse individuals). There are also studies where captive song birds increase complexity in the absence of other stuff to do. So I doubt this is an irreversible change.