Give or take a few hundred-thousand years, the period of greatest volcanic activity on planet earth occurred about 200,000,000 years ago and lasted for about 600,000 years. During this time, the Atlantic Ocean was formed. The first airplane flew along the shore of that ocean in 1903. And today, a volcanic eruption in Iceland has grounded some 28,000 airplanes across Europe, reminding us of how different human time is from either evolutionary or geologic time.