Thrillin' at the MacMillan #2: Sustaining the Planet© 2007 by Spider RobinsonSustaining the planet means widely different things to all of us—so let’s try and define our aim. The phrase surely isn’t meant literally. Terra was sustaining herself just fine for millions of years before the first oxygen-producing lifeforms infested her and wrecked her nice methane ecosystem, dooming entire phyla to extinction. Mother Gaia’s not alarmed by “global warming”: she’s survived vastly greater environmental changes more than once, and will again.