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The Spring 2011 issue of The Earth Scientist is focused on modernizing seismology education. Thanks to IRIS, you can download this issue for free as a pdf. Print copies are available in our online store.
Bacteria
Image courtesy of JPL/NASA

Pre-Cambrian Life

About 2.5 billion years ago (BYA) oxygen began to build up in the atmosphere. Life used this change to developed eukaryotic cells. These are cells which include a nucleus. Both heterotrophs (early animals) and autotrophs (early plants) began to use the new cells.

In cells with a nucleus respiration and photosynthesis are better, so the production of oxygen in the environment of the early Earth speeded up. This made it possible for new organisms which depended on oxygen for survival to develop.

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"Science, Evolution, and Creationism", by the National Academies, provides fascinating background on these topics for all, and is particularly useful for the Earth and space science classroom. Check our other books in our online store.

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