Friday, May 21, 2010

Luck, Preparation, and Opportunity: Part I

In the previous entry, I promised to ask and answer the question: how did The Great Cretaceous Walk come about? It’s a long story (by human standards) that could very conveniently start with me in 2005. But the truth is, it began a bit longer ago, in 1903. An Australian geologist, William Ferguson, was mapping rocks along the coast of Victoria, near the town of Inverloch, when he found a single claw, nicknamed the “Cape Paterson claw” (after nearby Cape Paterson). It turned out to be the first known body fossil of a dinosaur from Australia, and it came out of rocks from the Early Cretaceous, from about 115-120 million years ago. Its location was noted along with other bones, just southwest of a distinctive coastal feature called Eagle’s Nest. Here’s an excerpt of Ferguson’s map and his notations:

For now, also notice that Ferguson recorded “large ferruginous concretions in sandstone” just south of where he mentioned the presence of bones. These features would have significance much later, especially related to my study of trace fossils in this area.

Surprisingly, 75 years went by before more people looked for fossil evidence of dinosaurs in this area, when geologist Rob Glennie and two students, John Long and Tim Flannery, revisited the area in 1978. They found more skeletal material of dinosaurs and a previously unknown amphibian, which encouraged Tom Rich of the Museum of Victoria to examine geological maps of the areas east and west of Melbourne for more Early Cretaceous-age rocks. This led to prospecting of the Otway Group rocks to the west of Melbourne, and much walking along the coast: the original “Great Cretaceous Walk” (although they didn’t call it that).

All of the walking paid off, when in 1980 Tim Flannery, Mike Archer, and Tom Rich found a good number of dinosaur bones in rocks exposed along a cove. Well, Tom Rich named the cove that day – oh so nonchalantly – Dinosaur Cove.

This name not only stuck, it became world-famous as a final resting place for the remains of polar dinosaurs. From 1984 through 1994, tons of rocks were smashed, jackhammered, exploded, or otherwise abused to yield their 106-million-year-old paleontological secrets, and the results were spectacular, telling a detailed story of life on land near the South Pole at that time in earth history. This unique scientific endeavor and the human stories behind it are summarized in Tom and Pat Vickers-Rich’s book, Dinosaurs of Darkness (2000, Indiana University Press).

Once Dinosaur Cove was exhausted of its resources (and its volunteers were exhausted as well), a new dig site began in 1994, Dinosaur Dreaming. This dig site is in the kinder, gentler location of Flat Rocks, only a few kilometers from where William Ferguson originally found the first dinosaur fossil in Australia.

Now, keep in mind that these rocks are about 10 million years older than those of Dinosaur Cove, so the two places provide a “connect the dots” sort of view of how life changed in this area during the Early Cretaceous. Most significantly, this has been the site for many mammal fossils, some of the oldest in Australia. Hence a few people suggested that it be renamed “Mammal Dreaming.” But for some reason this new nickname hasn’t caught on, yet another example of how mammals haven’t gained much respect when used in conjunction with the word “dinosaurs.” And invertebrates? Forget it!

Well, you won’t forget for long, though, because I’ll soon point out how invertebrate animals fit into the larger picture of dinosaurs, mammals, and other denizens of these Early Cretaceous polar landscapes. My next entry will tell of when I visited Flat Rocks, in February 2006, and I first saw these Cretaceous rocks of Australia that never fail to surprise us with its paleontological wonders: Luck, Preparation, and Opportunity: Part II. See you then!

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