Study Catches Birds Splitting Into Separate Species
webdoodle writes "A new study finds that a change in a single gene has sent two closely related bird populations on their way to becoming two distinct species. The study, published in the August issue of the American Naturalist, is one of only a few to investigate the specific genetic changes that drive two populations toward speciation."
This was observed with the Eastern Rosella several decades ago, when the Murrumbidgee Irrigation scheme split the population in two. There are now two distinct species, that will not mate to produce fertile and viable offspring under natural conditions.
It is not speciation occurring ...YET. It is two related bird populations not seeing each other as sexual rivals, apparently because of feather colour. The article is clear. This MAY lead to speciation if other genetic changes occur in one or both bird populations.
"So if speciation has occured (according to the article) when the two populations no longer mate"
Re-read the article: it doesn't say so. It says that since those two populations no longer mate, the door is open for speciation to happen, not that it already has happened.
"does that mean if white people and black people stopped mating they would be different species?"
Change it for "they may end up eventually as different species" and you are right.