Background information Edit
According to the script notes, the writers originally intended for the people of Atlec and Straleb to be of different species. Specifically, Picard had originally stated that "Each of these planets is populated by separate humanoid people who coexist..." This was later revised to state that "Both worlds are populated by a humanoid race which colonized the planets two centuries ago and which now coexist."
Additionally, in this original premise, the writer noted that, for the Altec race, "perhaps one distinguishing factor to designate him as different;" while for the Straleb race, it was noted that "there could be a characteristic that would also mark them as an individual race and also slightly different than the Atlec race." This information was retained though the episode's final draft, but not presented onscreen.