My head is suddenly itching me like mad.

a trim lawn

Earless ghost swift moths become “invisible” to echolocating bats by forming mating clusters close[…]above vegetation and effectively blending into the clutter of echoes that the bat receives from the leaves and stems around them. Many insects probably use this strategy, which is a close analogy to crypsis in the visible world—camouflage and other methods for blending into one’s visual background.

Take it easy, bra!