From ScienceDaily:
Evolutionary biologists long have supposed that when species colonize new geographic regions they often develop new traits and adaptations to deal with their fresh surroundings. They branch from their ancestors and multiply in numbers of species.
Apparently, this isn’t the story of “true frogs.” The frog family scientists call Ranidae are found nearly everywhere in the world, and their family includes familiar amphibians like the American Bullfrog and the European common frog.
New research from the University of Kansas appearing in Royal Society Biology Letters shows, in contrast to expectations, “the rapid global range expansion of true frogs was not associated with increased net-diversification.”
…
Rather, the rich diversity of species in the Ranidae family comes from millions of years’ worth of continual evolution influenced by a host of different environs.
“Our conclusion is kind of anticlimactic, but it’s cool because it goes against expectations,” Chan said. “We show the reason for species richness was just a really steady accumulation of species through time — there wasn’t a big event that caused this family to diversify like crazy.” Paper. (paywall) – Kin Onn Chan, Rafe M. Brown. Did true frogs ‘dispersify’? Biology Letters, 2017; 13 (8): 20170299 DOI: 10.1098/rsbl.2017.0299 More.
Apparently, there is now an alarming lack of attention among life forms to what evolution experts say.
See also: Convergence: Wallabies do have placentas as well as milk that does placenta jobs
and
Life continues to ignore what evolution experts say