The Ediacaran. This is a span of nearly 100 million years that ends with the beginning of the Paleozoic Era (which begins with the Cambrian). The Ediacaran was a time when Earth warmed up after the colder Cryogenian times when glaciers covered much of the planet’s surface. Sometimes this period of time is called the Vendian Period. The International Commission on Stratigraphy has set the system period dates (pdf) for the Ediacaran from 635 millions years ago to 542 million years ago. The Ediacaran fauna are fossilized in rocks from approximately 600 million years ago to 545 or 550 million years ago. (There are websites that erroneously report widely different dates for the beginning of the Ediacaran period, confusing it with the Neoproterozoic Era or the Proterozoic Eon.)

Dickinsonia costata, a fossilized animal of the Ediacaran Era. It is difficult to figure out what sort of an animal this was, and how it is related to animals we know today.

A fossilized echinoderm of the Ediacaran Era.

A Pseudohizomites sp. This is a fossil impression from a creature that lived about 555 million years ago, in the Ediacaran Era.

1. David Morrison’s 2004 essay about the measure of deep time at NASA.
2. A page (mostly by Chris Clowes) at the Palaeos website describing the Ediacaran Era.
3. A description of the Ediacara Biota from The Miller Museum.
4. Some displays of life from the Ediacara Era from The Dinosaur Collector.
5. There is some confusion about just what was alive in the Ediacaran Era. The University of California at Berkeley mentions this, and an old (1990) article from New Scientist by Simon Conway Morris offers some questions about early life (although most of the article is about the Burgess Shale, which represents a time after the end of the Ediacaran Era).

Articles of French history:Eiffel tower, Louvre, Versailles, Notre-Dame de Paris, Paris Opera house.

Articles of Chinese history: oil well, abacus, compass, gunpowder, first dictionary, paper money, wheelbarrow.

This work by Eric & Chun-Chih Hadley-Ives is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.