@jpm, Somehow I just figured you’d like this article !
This is just a portion of the article…
This could become the classic case of how non-genetic factors (in this case, bird song) can lead to speciation!
“Back in 1981, researchers working on a tiny volcanic island north of Santa Cruz called Daphne Major noticed a strange bird that didn’t look like anything typically found on the remote dot of land. It was larger and built differently than the few bird species native to the island and it also sounded different. It was clear that the bird wasn’t from Daphne Major, but its origins were unknown, so the scientists caught and tested the bird’s blood before releasing him. What happened next was a shock to the scientists.”
“Not content to live out his life on the island where he clearly didn’t belong, he actually managed to find a mate among the native finch species, resulting in hybridized offspring that were a mix of the two. These new unnamed birds were called simply “Big Bird” because they were larger than the native species, and while it was strange on its own, nature had one more curve ball in store for researchers.”
“After reaching maturity, the new Big Birds attempted to find mates of their own, only to be met with a big problem. The hybrid birds couldn’t replicate the song of the native finches and that, combined with their difference in size, prevented them from attracting mates. What they did manage to attract was each other and interbreeding resulted in more and more Big Birds on the island. Now, six generations later, the hybrids are their very own established species.”