Gender and sexual identity are on many minds right now. There are continuing legal battles over bathroom access; piles of gossip items about Caitlyn Jenner; the third season of “Transparent” is likely to be a highlight of fall television.

For those used to dividing the world neatly into male and female, the new way of thinking feels, well, new.

But, of course, these complexities are as old as humanity. A glance through the exhibition “Pergamon and the Hellenistic Kingdoms of the Ancient World,” now at the Metropolitan Museum of Art, shows how long they’ve fascinated us.

This show of works from the far reaches of the Roman Empire drives home another point, too. In 2016, embracing the ambiguities of gender and sexual identity can be a way to signal open-mindedness. And even in this, ancient civilizations were ahead of us.