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| | Lab Notes |
 | | These early animals are also invisible to us, too small and soft to form good fossils, but during the Vendian period, from 700 million to 550 million years ago, some of them managed to develop the crucial gimmick of segmentation. |
 | | And when that deadly cap finally came off, as volcanic CO emissions heated the atmosphere again and melted away the ice, those plants and animals which survived had 50 to 70 million years of peace in which to quietly reconquer the oceans. |
 | | Eventually, around 1 billion years ago, organized colonies of these creatures gave way to the first multicellular animals: probably microscopic sponges with an outer skin, a tissue layer, an inner digestive canal and (importantly) the capacity to evolve new tissue types, such as muscle. |
| www.scifi.com /sfw/issue283/labnotes.html (450 words) |
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