Please send in your good wildlife/travel/people photos, as the tank gets ever lower. . . . .
Today is Sunday, which means we have a batch of bird photos from biologist John Avise. The narrative and IDs are his, and you can enlarge the photos by clicking on them.
Sibling Species
By definition, avian sibling species are closely related but reproductively isolated species that are nearly indistinguishable in the field by their plumages. In ornithological circles, perhaps the most famous complex of sibling species involves the Empidonax flycatchers (or “empids” for short), of which about a dozen look-alike species breed in various parts of North America. Today I share my photos of several empids, probably none of which will you be able to tell apart by appearance. So how did I identify these species when I took their photos? I did so by their song, behavior, range, or habitat, all of which differ characteristically among various empid species. For example, only the Gray Flycatcher of Western North America consistently pumps its tail while perched, and only the Acadian Flycatcher of the Southeastern United States has an explosive “spit-a-KEET” song. Anyway, happy birding!
Acadian Flycatcher (Empidonax virescens):
Gray Flycatcher (Empidonax wrightii):
Hammond’s Flycatcher (Empidonax hammondii):
Another Hammonds Flycatcher:
Dusky Flycatcher (Empidonax oberholseri):
Pacific-Slope Flycatcher (Empidonax difficilis):
Another Pacific Slope Flycatcher:
Yet another Pacific Slope Flycatcher:
Yellow-bellied Flycatcher (Empidonax flaviventris):
Willow Flycatcher (Empidonax traillii):
Very good! Lots of examples of allopatric and maybe sympatric speciation are presumably in these birds.
Beautiful birds! Those flies don’t stand a chance.
How do you send in photos?
You’ll see our host’s email address if you click on the “Research interests” link below this comments section.