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This clip shows Reginald Sprigg revisiting the site in the Ediacaran Hills of the Flinders Ranges in South Australia where, as a young mining geologist in 1946, he discovered fossils of the oldest known life forms on Earth. Sprigg talks about the discovery, a narrator tells of the significance of the find in the history of palaeontology and examples of Ediacaran fossils are shown. These fragile fossils are now housed in the Museum of South Australia in Adelaide.

Educational value points

• The clip re-creates Sprigg’s 1946 discovery of fossils in the Ediacaran Hills, which resulted in a new worldwide interest in Pre-Cambrian palaeontology and increased our knowledge of the origins of life on Earth. Ediacara, a local Aboriginal word for a spring of water (after which the hills were named) also gave its name to the group of life forms that formed the fossils – the Ediacaran biota.

• The fossils shown in the clip provide us with a view of some of the first animals to live on Earth. These creatures from the late Pre-Cambrian age, which ended 560 million years ago, lived in the warm tropical seas that covered what is now the Flinders Ranges. Some resemble modern jellyfish, soft corals and flatworms, while others are unlike any living species and remain unclassified.

• The Ediacaran Hills where Reg Sprigg made his find gave their name to a new era of geological time, the Ediacaran Era, in 2004. This was the first time in 120 years that a new geological time division had been named. The start of the Ediacaran Era is marked in the rock strata in Brachina Gorge by a ‘golden spike’. This spike in the Flinders Ranges, south of the site of Sprigg’s discovery, is recognised worldwide by geologists as marking a world standard.

• Fossils of Ediacaran organisms have now been discovered in 30 or so localities over five continents, including England, India, Iran, Canada and Russia. The principal occurrence remains in South Australia’s Ediacaran Hills, but the earliest fossil organisms, dating from 575 to 560 million years ago, have been found in Newfoundland in Canada.

• Since their discovery by Reg Sprigg, the Ediacaran fossils have been the subject of an evolutionary dispute among palaeontologists. The question is whether Ediacaran fauna are ancestors of Cambrian multicelled animals and thus related to life forms existing today or whether they represent a ‘failed experiment’ by nature, which died out.

• The clip shows the way a scientist can pursue theories in opposition to currently held scientific viewpoints. Reg Sprigg describes the way he applied knowledge obtained in one setting to look for fossils in another, the Ediacaran Hills. At the time of his discovery scientists believed it was impossible for early life forms (with their soft bodies) to be preserved in ancient rocks such as those found in the Flinders Ranges of South Australia.

• The clip provides an example of how scientific knowledge changes when new evidence is discovered. When the film was made in 1970, Sprigg believed that the fossil Ediacaria flindersi, probably the commonest and most widespread of all the Ediacaran fossils, was formed by a creature resembling a jellyfish. It is now commonly believed that the disc shape was formed by a circular ‘foot’ that secured a polyp or soft coral to the sea floor.

This clip starts approximately 14 minutes into the documentary.

Footage of the landscape and fossils of Ediacara is interspersed with an interview with Reg Sprigg at the site, who we have seen examining flat pieces of stone on the ground.
Narrator Here in 1946, at a place called Ediacara, was made one of the most important fossil discoveries of the century, although at the time it seemed so extraordinary that nobody believed it. The find was made by Reg Sprigg, a geologist with the South Australian Government. During the course of a routine survey, he’d found this hillside, covered with flat pieces of weathered sandstone that seemed very old. One day, Reg Sprigg came back.

Reg Sprigg Well they – they are so beautifully flat-bedded that as they were sea-floor sands, ah, one felt that there was a fair chance that you’d get impressions preserved on them. Normally a sandstone is considered a most uninviting environment for preservation of life, but I had seen, down near Adelaide, a most magnificent fossil, which was later lost, unfortunately, that made me want to look in the same horizon here. And the very first day I stepped on this hill I walked onto one and got a number.
Interviewer What did you find?
Reg Sprigg Well, that was a beautiful jellyfish called Ediacaria. This sort of one is another example of it – about that same size. But unfortunately, I got several and none of my fellow palaeontologists at the time would accept that they were fossils.
Narrator Until then no-one, anywhere in the world, had found anything in rocks of this age other than extremely simple, minute organisms, until Reg Sprigg found his jellyfish.

We hear dramatic drum music and see a close-up of fossils including the now-famous Mawsonites spriggi jellyfish.
Narrator This specimen, now in the Adelaide Museum, is called Mawsonites spriggi. It’s named after both Sprigg and his former professor of geology in Adelaide, Sir Douglas Mawson. Besides exquisitely-preserved jellyfish, Reg Sprigg found other relatively advanced forms of Ediacaria, including these large flattened worms. Some species of segmented worms that Sprigg found at Ediacara have been named Spriggina. Other fossils found there, like this three-branched animal, bear no relation to any living species and remain unclassified. This shield-like animal is one such mystery. Nothing like it has ever been found anywhere in the world.

We cut back to Reg examining the hills of Ediacara.
Narrator Today Reg Sprigg is a successful businessman in the field of mineral exploration. But he also has a strong personal involvement in the Flinders Ranges. He owns and operates the Arkaroola Resort and Geological Sanctuary as a sideline. He also likes to visit the hillside at Ediacara now and again and remember that day, back in 1946, when he pushed back our knowledge of the development of early life by 100 million years or so.