Firefly Glen nightmare

How do they know? She asked him, still not having moved from her spot beside him. He had not moved away, after all, so she figured it was alright. They do not have ears, or eyes... The valkyrie mused aloud, frowning slightly as she worked her way through her thoughts. They cannot think, I think... A gentle tilt of her head, before she looked to him once more. Do the insects tell them, somehow? Maybe that was it, the secret to the flowers opening for them at night.