Has anyone else noticed that inside the pyramid ships, or at least the largest one in the middle, there are moth like particles flying around inside it? If the Traveler is Light, and the Darkness is drawn to it, the Darkness race might very well be the moth race we've seen in concept art. And as moths, they are drawn to the flame. Bungie is really latching onto the moth meme. But seriously though, the Darkness are most likely the humanoid moth race. They start as those worms that the Hive incubate, and either continue to feed to become giant Worm Gods or metamorphosis into the Moth race. And if they are Moths, then they have existed long before the Hive have. And the Hive have existed long before Humans have.