I had written in a recent post: "Cowbirds are quite common. Habitat is forest edges, also farm yards. Originally they apparently co-evolved with bison and it has been hypothesized they developed their parasitism as a mechanism to breed and leave their young behind as they followed the bison."
While I can well document that information, Tony Hertzel informed me: "Current thinking among evolutionists says that brood parasitism in cowbirds first evolved in South America millions of years before Brown-headeds were around and well away from any bison. The concept of the species co-evolving with bison makes no sense when you think about how that might occur." I can definitely see how that hypothesis could have been developed with little factual information to support it. Thank you, Tony! Steve Weston On Quigley Lake in Eagan, MN swest...@comcast.net ---- Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net Archives: http://lists.umn.edu/archives/mou-net.html During the pandemic, the MOU encourages you to stay safe, practice social distancing, and continue to bird responsibly.
