Sunday, June 1, 2014

Aalenian

The Aalenian is a subdivision of the Middle Jurassic epoch/series of the geologic timescale that extends from about 175.6 Ma to about 171.6 Ma (million years ago). It was preceded by the Toarcian and succeeded by the Bajocian.

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lordosis

  Lordosis is historically defined as an abnormal inward curvature of the lumbar spine.