The Ectasian (from Greek "ectasis", "extension") is the second
geologicperiod in the Mesoproterozoicera and lasted from 1400 Ma ago to 1200 Ma (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically.
Name derives from continued expansion of
platform covers during this period.
Evidence of a eukaryotic
red algae, " Bangiomorpha pubescens", has been identified from ca. 1200 Ma old rocks in the Hunting Formation( Somerset Island, Canada). This is the oldest known sexually reproducing organismand therefore the earliest known complex multicellular organism. [http://paleobiol.geoscienceworld.org/cgi/content/abstract/26/3/386]
*cite web | title=Ectasian Period | work=GeoWhen Database | url=http://www.stratigraphy.org/geowhen/stages/Ectasian.html | accessmonthday=January 5 | accessyear=2006
*cite journal | author=James G. Ogg | title=Status on Divisions of the International Geologic Time Scale. | journal=Lethaia | year=2004 | volume=37 | issue= | pages=183–199 | url=http://www.stratigraphy.org/precambrian/Ogg_2003.pdf | doi=10.1080/00241160410006492
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