The marine biologist filmed the tide pool over four days. Each morning the water crept higher, life blooming in every crevice — anemones and urchins claiming each inch of rock. By the third morning every cell of her observation grid was alive. But that afternoon a rogue swell crashed over the south wall of the pool, scouring the bottom row clean of everything that had taken root. The next tide brought new larvae, and by the fourth morning the pool was full of life again, as though the wave had never come.