Nature is constantly looking at us, human and otherwise. We are a curious bunch!
The experience of 'looking back' is multi-faceted: it expands with practice.
Two-eyed creatures are readily engaged in a mutual appraisal. People with pets know this. Dogs and cats and horses, for sure. Budgies and turtles and guppies are more fleeting and more dramatic. Nature unfettered gives the satisfaction of something wild captured for a brief moment in a stare: chickadee, seal, ladybug, heron, slug..........
A rock is one big eye.
Gaze on a tree in its winter bare state and wait on the realization that it is a multitude of eyes; in summer the leaves are its eyelashes.
A willow tree just after a rain, when the sun pops out and the wind shows off the shimmer, wins its staring contest with me: I have to close my eyes in overwhelm.