David was a yawner. Every time he opened his mouth, the colony of Tannerella forsythia rejoiced in adulation.

“Oh man, I love it when he yawns!” proclaimed one bacterium.

“Gotta love the fresh air,” piped another.

David was such a yawner, in fact, that the colony could practically set their chrono-flagella by it. Ever 120 seconds, David would open up his mouth real wide to scoop in some much needed oxygen. And every 120 seconds, the colony doubled in size.

What started as a single bacterium, only 1 hour previously, was now over a billion strong. And still growing, thanks to the ripe conditions provided by David’s tongue and yawning habits.

As David opened his mouth again, little ones were jumping for joy, as this would be their first Yawn. As the chasm widened, the older ones joined in the celebration. As it approached Fully Open….

“Help!”

“I’m drowning!”

The deluge was almost instantaneous. The whole colony destroyed, save one. Surely, the process would repeat itself.