In Exercise Ball: Our World Transcript — 23 September 2006 | Science and Technology ...

MUSIC: "Our World" theme Straight ahead on "Our World" ... 'Safe' levels of lead aren't ... A three-million year old skeleton ... and an unlikely environment story ADELMANN: "Tall grass prairie remnants, oak savanna. Some of our wetland communities and so forth are extraordinarily rare, rarer than the tropical rainforest." And that's the big city of Chicago he's talking about. Those stories, voice ...Exercise Ball