Extinction: A large Scale Random Transformation

Potential Triggers Asteroid Impacts = sudden

Gradual: Large Basalt Outflows Large CO2 changes which can affect atmospheric and ocean chemistry (slow) an “oh shit” event

65 Million years ago KT extinction (dead dinosaurs) triggered by asteroid impact. A 10km diameter asteroid, leaving a crater ~200 Km in diameter Impact caused acid rain, ash (from global forest fire) that directly blocked out the sun for months, severe global cooling (nuclear winter).

Many events of varying extinction percentage amplitude The struggle Relatively stable

Five Agreed Upon Major Events

Co-Evolution & Niches Any species living in a niche has evolutionary relationships with other species; some casual, some crucial Therefore, the extinction of a species will have repercussions in the niches of all species which have co-evolutionary relationships with the newly extinct species

Implications: Evolutionary Clock gets periodically reset Life recovers (relatively rapidly) to fill new ecological niches  this empowers species diversification This means that “survival of the fittest” doesn’t work on long timescales  random catastrophe is MORE important Strangely, nature confirms that a “new world will arrive out of the ashes of the old one”