New geological time period added to earth’s history, according to BBC News, 18 May 2004. The new period extends from 542 to 600 million years ago and will be known as the Ediacran period. This puts it just before the Cambrian period on the geological column, and it is believed to be the time when multi-cellular organisms evolved.
The name Ediacaran comes from a region in Australia known as the Ediacara Hills in the Flinders Ranges of South Australia, where fossils of simple multi-cellular creatures such as jellyfish have been found. A layer of rock named the Enorma Creek section of the Flinders ranges has been designated the “boundary stratotype” for the Ediacaran period. This means it will be used as the standard for comparing other rocks that could be classified as belonging to the Ediacaran period.
Editorial Comment: This reminds us how names in the geological column were originally given. Some of the names, such as Cambrian, Jurassic and Devonian and the new Ediacaran rocks, refer to the place where rocks with a distinctive structure (or fossils) were first studied. Cambria is an old name for Wales (UK), Jurassic rocks are named after the Jura Mountains in Europe, and Devonian rocks were first studied in Devon, England. Other names such as Triassic and Cretaceous refer to the appearance of the rocks, i.e. Triassic rocks contain three colours, Cretaceous rocks are chalky. Either way, the rock names relate to the structure and appearance of the rock, and have nothing to do with time or evolution.
The link between rock names and time only occurred after Lyell and his followers (1830 ff) claimed rocks formed gradually and fossils represented the history of life on earth. As this editor has searched widely over the Australian Ediacara Rock formation I can be very dogmatic – the fossils there provide no help to the theory of evolution, and the presence of vast numbers of soft bodied jelly fish fossils is wonderful evidence of rapid deposition. (Ref. Ediacara, geology, time)