Patrik Nosil gathered “walking stick” insects from one location and put them in another. He and his co-worker found that coloration patterns, such as a white line along the body, changed as they adapted to a new location. Then, the ones that could detoxify leaves of unfamiliar plants survived to “seal the deal” of speciation.(a little after the list of items)
Creationists might agree that the two species in the study had a common ancestor anyway.
So, we have an experiment which attempts to show speciation happening in the field. The results are perhaps a bit questionable...and in their formal paper they say so.
But I had to do a double take on the latter comment about creationists accepting that the two (or was it just one?) new 'species' had developed from the same ancestor... Surely that was the point that was apparently being refuted.