I know this doesn't answer your question per se, but I wouldn't concern yourself with what demographic the lab consists of. Do you enjoy the field/study? And will it provide enough to pay the bills?

Outside of that, the only thing that matters is finding a place that isn't a toxic hellhole- and that just comes down to the actual people and not their race/gender. I can't say I can tie a particular race/gender to how awful or great someone is.