in his best Sir David Attenborough:What about the Duras sisters? From their costumes in TNG and DS9 they quite obviously didn’t have scales on their... um... unmentionables like we saw when L’Rell and AshVoq were canoodling. I can’t even
Klingon evolution is complicated by a variety of specializations caused by Kronos' turbulent seasonal changes, budgets, and developer whims. Lack of chesticle scalular development causes attraction from what Starfleet scientists call the "Uno-Peener" variety Klingon mate, also identifiable by hair or eyepatch while those with scales use the olfactory glands in the pits in the back of their skull to search out a fine peaty-smelling pheromone from their own preferred kind. The female then travels 50 billion miles to a small rocky island in the ocean to lay her eggs.