Friday, September 30, 2011

The Great Cretaceous Walk Takes a Rest

About six weeks ago, I shared the happy news of our discovering dinosaur tracks at Milanesia Beach, Victoria, which turned out to be the largest collection of polar dinosaur tracks known in the Southern Hemisphere. Those tracks were found during the month-long excursion (May-June 2010) along the Victoria coast that inspired the start of this blog. And although we found heaps more trace fossils, the tracks constituted out most important scientific find. So even though we have a but more science to do, this is as good of a time as any with this blog to say, “Catch you later” and make a transition both geographical and temporal.
The Great Cretaceous Walk has been very, very good to me. But it’s time to take a pause in all of the walking and talking about the Cretaceous of Australia, and look closer to home (Georgia) and at this time in the present (otherwise known as “now”). Photo by Tom Rich, and taken on May 28, 2011 (Day 2) of our month-long field survey of the Cretaceous trace fossils of Victoria.

Sunday, August 14, 2011

Discovering the Dinosaur Tracks of Milanesia Beach

(In my previous entry, I described the start of a day in the field – June 14, 2010 – at Milanesia Beach, Victoria (Australia), just hours before Tom Rich, Greg Denney and I discovered the largest assemblage of polar dinosaur tracks in the Southern Hemisphere. In that entry, I also pointed out how few dinosaur tracks had been documented in Victoria before then, which also meant very few polar dinosaur tracks had been found in the Southern Hemisphere. This background gave some context on why this find is a big deal, paleontologically speaking. So, would you like to want to learn how these tracks were discovered? Then read on.)

As Tom Rich, Greg Denney, and I walked down Milanesia Beach the morning of June 14 2010, my thoughts were about the dearth of dinosaur tracks found thus far in Victoria, Australia. Geological research of these Cretaceous-age rocks had been going on for more than 100 years, and paleontological studies there had been particularly intense during the past 30 years. Yet during that time, only four definite dinosaur tracks had been discovered in all of the extensive Cretaceous outcrops of coastal Victoria. Moreover, all of these were individual prints, with no dinosaur trackways showing at least two sequential steps. The previous three weeks of field work Tom and I had done along the coast seemed to bear out this notion that dinosaur tracks were rare here, even scarcer than their bones.

Nonetheless, I also tried to shake a premonition, experienced only a half hour after arriving at Milanesia Beach, that we might find dinosaur tracks there. Rest assured, this hunch was not inspired by séances, Ouija boards, psychic-pet hotlines, or any other forms of necromancy. Instead, it was based on our seeing the physical sedimentary structures and small invertebrate trace fossils (burrows) that told me we were looking at the former deposits of river floodplains. These environments would have been perfect for preserving dinosaur tracks. Regardless, I reminded myself to just be a cold, clear-headed, objective scientist: you know, a pessimist.

 A few more of the dinosaur tracks of Milanesia Beach, Victoria (Australia). Three size categories were there: small, medium and large, all made by three-toed theropod dinosaurs. Greg Denney found the ones shown here, which he discovered by recognizing how this rock matched another one with dinosaur tracks that I had found just a few hours before. Please buy him an adult beverage next time you see him, slap him on the back, and say, “Good on ya, mate!”

Tuesday, August 9, 2011

The Dinosaur Tracks of Milanesia Beach: Part I

Because of the sparse and uneven record of dinosaurs in Australia, their fossil footprints are more valuable here than anywhere else on Earth.

- Thomas H. Rich and Patricia Vickers-Rich, A Century of Australian Dinosaurs (2003).

The Preamble

Dinosaur tracks are hard to find. This humbling realization struck me during the third week of a month-long field excursion in May-June 2010, while doing field work along the craggy coast of Victoria, Australia. Why was I there, engaging in such an apparently fruitless quest? Paleontologist Tom Rich of Museum Victoria had invited me to look for trace fossils made by dinosaurs and other Cretaceous animals that might be preserved in the rocks of Victoria. Yet as was often the case with looking for fossils of any kind, there were no guarantees of success. He and I had already searched more than a hundred kilometers of coastal cliffs and platforms east of Melbourne, and were then working our way through sites west of there.

Here are four three-toed dinosaur track,s preserved on a block of sandstone at Milanesia Beach, Victoria (Australia). They’re faint, but there – look closely for all four. These tracks were probably made by small theropods on a river floodplain during a polar summer about 105 million years ago, when Australia was close to the South Pole. On June 14, 2010, I discovered the block that contained these tracks, and a few hours later, Greg Denney found another block with more tracks. This is a big deal, as they represent the greatest number of polar dinosaur tracks found in any one place in the Southern Hemisphere. It’s enough to make you want to do a happy dance. Scale bar in photo (lower left) = 10 cm (4 in).

Monday, July 18, 2011

Cruising the Cretaceous of Queensland: Student Edition

Earlier this month – July 4-8, 2011 – was my third time to see the wondrous Cretaceous fossils of Queensland, Australia. But it was my first with university students in tow to share in that paleontologically inspired excitement. Our trip together to outback Queensland was during the third week of a five-week program for Emory University students taking a study-abroad program in Australia, taught by me and my good friend (and oh yeah, colleague) Steve Henderson from Oxford College of Emory. We did this trip to give them a taste of what life was like in the modern-day outback and 100 million years ago during the Cretaceous Period, when theropod dinosaurs like Australovenator wintonensis (“Banjo”) likely chowed down on hapless ornithopod dinosaurs, and the whopping pliosaur Kronosaurus queenlandicus was ruling the inland seaway that covered much of the area we saw during our trip.

Paleontological innocents abroad, about to get acquainted with the past lives of outback Queensland. And who could resist posing with a life-sized recreation of the large ornithopod dinosaur Muttaburrasaurus langdoni, located in Hughenden, Queensland? Well, OK, I told them their grades depended on it, so they quickly got into the spirit of things.

Sunday, July 3, 2011

Teaching the Past, Cretaceous and Other Times

It’s a safe generalization to say that academic paleontologists devote much of their time and energy to educating non-paleontologists about the wonders of past lives. This lofty goal might be accomplished in an official capacity as a university professor or a museum researcher, or unofficially through public speaking, publishing popular-outreach books, or – to be totally modern, hip, and self-referential – writing a blog. In this instance, I am mixing official and unofficial duties by sharing a few of my experiences with teaching paleontology to undergraduate students at my university (Emory) during a study-abroad program in Queensland, Australia.

A happy group of American university students, which is as they should be, because they are in Queensland, Australia learning about its paleontology. Little do they know their state of fossil-induced bliss is about to be interrupted by a lurking Early Cretaceous pliosaur, Kronosaurus, inexplicably occupying an aerial environment and in the present. (I’ve been trying to tell them all along that some things are worse than a failing grade.) Photo taken by me at the Museum of Tropical Queensland in Townsville.

Sunday, June 12, 2011

The Dinosaur Tracks of Western Australia May Go Extinct

You really have to want to visit Broome and nearby environs in the Kimberly region of Western Australia, because it’s a long ways from nearly everywhere else in the world. Even of the Australians I’ve met, relatively few have been there, despite Broome’s beautiful beaches, camel rides on those beaches, a wonderful open-air theater (the oldest In Australia), pearling history, longtime connections to Asian culture, small-town feel, and charming locals. Oh, and its dinosaur tracks, which of course was one of the reasons why I was motivated to go there with my wife Ruth in 2009.
Anyone up for some “ichnotourism”? At low tide near Broome (Western Australia), you can see some of the biggest dinosaur tracks in the world, made by sauropods about 130 million years ago. Or, you could put a gas-processing plant on top of them and build a port, which will generate absolutely no ichnotourism, stuff up the local environments, and if anything drive people away from the area. Hmm, tough choice: (A) short-term profits benefiting a few people and causing lots of collateral damage, vs. (B) preserving a world-famous natural resource, coastal environments, and cultural heritage that will continue to give back tourism dollars to the local community in perpetuity. Not to bias you, but I’m going with (B). (BTW, lovely wife Ruth for scale.)

Friday, April 29, 2011

Kronosaurus: The King (or Queen) of the Queensland Sea

Life was good during the Early Cretaceous – about 110 million years ago – in what would some day become Queensland, Australia. That is, life was good for whatever was making tucker out of whatever else was alive at that time. In that sense, then, when it came to the Cretaceous seaway that covered much of inland Australia then, few animals enjoyed life more than the giant marine reptile Kronosaurus queenlandicus.
Fancy a dive in the Cretaceous sea of Queensland? You’d have a lot more to worry about than running into a box jellyfish, blue-winged octopus, or great white shark, mate, like a bloody huge Kronosaurus. Artwork is on a tapestry (batik?) in Kronosaurus Korner, Richmond, Queensland, and the presumed artist is Paul Stumkat, who’s also the curator and fossil preparator there. (When you do paleontology in central Queensland, you have to wear a lot of hats.)