Danger amongst the duckweed

We saw each other and froze....eyes fixed, locked together. Evolved senses kicked in: who was the predator, who was the prey? Played correctly, this could be resolved without it coming to blows, but what did we have in common - what could be compared in order to make a judgement call over fitness?

The sound of birds filled the otherwise tense silence. Seconds passed like hours. Then a single trickle of sweat dripped down the side of my temple and gave the game away. He knew; his eyes narrowed ever so slightly and he brushed me aside with a casual glance away to nothing in particular on the pond bank. As my crest continued to fall, a final look back merely said, "You still here?"