Wednesday, March 30, 2011

Keeping Track of Fossil Tracks


The fossil thieves drove their sport ute into the Western Australia outback in the middle of the night, confident that no one would see them. Just to make sure, though, they turned off their headlights the last kilometer before their destination, using moonlight to keep their tires on the unsealed road. Once at the site, they used torches (flashlights) to search the ground, and quickly found what they were seeking. They pulled out a portable rock saw from of the back of the vehicle and cut through the 120-million-year old sandstone, the abrasive sound masked by nearby waves crashing during high tide. The sandstone bed was thick, but split evenly along its bedding plane so the thieves were able to use a lever bar to pry up each square. These blocks were heaved onto the truck bed; blankets were used to cushion them below and cover them above. The perpetrators got into the truck and sped away from the site, well before the first rays of the morning sun revealed the newly made and oddly square holes in the rock. They had just taken some of the few stegosaur tracks known from the geologic record, and they had stolen these from aboriginal tribal land. It was both a crime against the state and a grave insult to the people who regarded these tracks as part of their heritage.


Nice dinosaur track you got there. It’d be a shame if something happened to it. Track is from a large theropod dinosaur, preserved in Early Cretaceous sandstone of Western Australia. Please don’t take it, legally or otherwise.


The preceding scenario is partially fictionalized, but based on an incident that actually happened in Western Australia in 1996. Paleontologists had been negotiating with indigenous elders to study the tracks, which had been considered as part of their Dreamtime stories; hence this was a sacred site for thousands of years before Europeans and others arrived in that area. The stegosaur tracks were recognized by the paleontologists in 1991, and were similarly regarded as “sacred objects” by these scientists in their own way, but for their scientific value.

So what was the big deal about these tracks, and in a paleontological sense? Stegosaurs were at that time unknown from Australia, with not a scrap of bone indicating their former presence on that continent, despite their abundance in Mesozoic rocks of North America, Asia, and Africa. Even now, 15 years after the tracks were stolen, no one has yet identified a stegosaur body fossil from anywhere in Australia. Even more significant, stegosaur tracks are apparently much more rare in the geologic record worldwide than their skeletal parts. A few have been reported from Europe (Poland, the U.K., and Portugal), and Africa, but only two from North America. This situation – the opposite for most trace fossils, which normally outnumber body fossils – also means that the Australian stegosaur tracks would have contributed to a better understanding of how stegosaurs walked or otherwise behaved in this part of the world during the Mesozoic Era.


Trying to find stegosaur tracks? You’re better off looking for their bones, especially in North America. But you may have your work cut out for you (pun intended) in Australia. Specimen is of Stegosaurus stenops and is in the Carnegie Museum of Natural History.

The Australian paleontologists, once they recognized what they probably had, agreed to limit their time studying the tracks. Of course, they also would not collect these tracks for a museum because of their spiritual importance. Besides, any extraction of them would damage the rock that had held these tracks for millions of years and, in the eyes of the elders, would change their Dreamtime.

Once permission was gained to study the tracks, though, word somehow got out about them, and a terrible thing happened. Professional fossil collectors, looking to sell the tracks to a buyer, went to the site and cut out the tracks with a rock saw. Amazingly, one of these tracks was eventually recovered and a suspect arrested. Nonetheless, no one knows what happened to all of the tracks, although they presumably ended up in private hands of a wealthy fossil collector. What is known, though, is that the trust between the indigenous people and the paleontologists was violated, perhaps irreparably. Worst of all for science, unless miraculously recovered, the stegosaur tracks will never be described or interpreted. (As an aside, I hope that the people who did this will get a visit from a Wandjina some day.)


G’Day! Heard you stole some sacred objects from our Dreamtime. Bad move, mate. Who’s your daddy? (Artwork by Ruth Schowalter (a.k.a. Hallelujah Truth.)

Nonetheless, this incident also relates to a thought I’ve wrestled with in recent years. (No, not about the premature cancellation of the TV series Farscape: everyone knows that was wrong.) However heretical it might seem for an academic paleontologist to say, I sometimes disagree with the sentiment that all fossil specimens belong in a museum. In my opinion – which, like most opinions, is actually never humble – some trace fossils, such as dinosaur tracks and other vertebrate tracks, are better left where they were found. Why? Because our knowledge about them will not always be enhanced by taking them away from their places of origin. This is especially the case if we know these trace fossils were recognized by local indigenous people and became part of their cultural heritage.

For example, while once on a field trip organized by academic paleontologists, we visited a site that used to have fossil vertebrate tracks. Notice I said, “used to have.” As we walked up to the former location of the tracks, I was shocked to find out they had been collected by other academic paleontologists, instead of being left in the context of their original ancient environments. Even more vexing, the tracks had been lying next to Native American petroglyphs that depicted tracks looking very similar to the fossil ones (maybe coincidental, but probably not). The petroglyphs had been made by indigenous people living in that same area more than a thousand years beforehand. Thus the separation of the fossil vertebrate tracks from the petroglyphs resulted a greater loss of context, but this time cultural.

I expressed my dismay to the field-trip leader by asking, “What are they [the tracks] doing at [name of prestigious institution]?” The bemused and condescending response was, “That’s where they belong!” (You know, like the Indiana Jones line, “It belongs in a museum!”) This was followed by some semi-serious joking about how they wanted to collect the petroglyphs too, but archaeologists studying the site insisted against it. (And they would have gotten away with it too, if it weren’t for those meddling kids, er, I mean, archaeologists.) All of this was legal, done with proper permits, through well-known institutions, and was carried out by credentialed individuals through their respective (and respected) institutions. Yet I found it unsettling.


Native American depiction of a three-toed track in the western U.S., pecked into a Mesozoic sandstone. Was it representing the nearby track of a theropod dinosaur, or of a modern bird? Probably of a bird, because of the little dot at the bottom, representing a backward-facing thumb (hallux). But wouldn’t it be nice to be able to compare them directly with theropod dinosaur tracks in the same area?


Guess what: you can! This Middle Jurassic theropod dinosaur track is at the Red Gulch Dinosaur tracksite in Wyoming (USA), and only a few hundred meters away from Native American petroglyphs. By the way, it, hundreds of other dinosaur tracks, and the Native American petroglyphs are under U.S. federal protection. So don’t even think about it.

Yes, I know how the collection of fossil specimens by a museum helps to preserve these in perpetuity, and make them available to researchers for future generations. Plus I totally understand paleontologists taking body fossils away from a field site so these can be carefully extracted in a lab and made ready for detailed study. But I wonder whether it is worth taking away trace fossils related to the heritage of living people. We now know that fossils, including fossil tracks, probably inspired many spiritually oriented stories in indigenous cultures. In such instances where such connections can be demonstrated, perhaps it’s better to leave fossils – especially trace fossils, which often need no further preparation to be studied – where they lie.

What’s the alternative to collecting for scientists who want to make these specimens available for others to study: you know, that peer-review thing we scientists claim we like so much? One word: lasers. That is, laser scanning is now providing a way to make three-dimensional computer-generated images of fossil tracks that can be studied, shared, and archived like real tracks. The tracks can still be kept in the field, with their localities kept confidential so only qualified researchers should gain access to them. But laser scans will also insure that if the tracks weather, are damaged, or stolen, paleontologists still have a means to evaluate the information they hold for generations to come.


It’s not sharks with laser beams on their heads, but it’s pretty close from a media-hype perspective: dinosaur tracks and lasers, in which the lasers are used to scan and make images of the tracks. Image from Photonics, Inc., based on a study led by Marco Avanzini of geology department the Museo Tridentino di Scienze Naturali (Italy).

For paleontologists who do not have ready access to laser scanners (let me check – nope, no lasers here), old-fashioned molding and casting can also be a way to create a reasonable replica of a fossil track. Of course, experienced people should be the ones to apply this technique to avoid damaging the tracks, but it also does not always have to be done by professional paleontologists. Replicas of fossil tracks can be made by non-professional paleontologists and sold as substitutes for the real thing, while still being appreciated for their beauty and scientific worth.


Is it real? Yes, it’s real. Oh, you mean, is it a real dinosaur track? No, but it’s a real replica of a theropod dinosaur track, which was probably from the Early Jurassic of North America. After all, I’m not studying it, just admiring it. And as a colored resin cast, I can hang it on a wall and not worry about it crashing to the ground and destroying a vestige of the geologic past. Gorgeous photo by Ty Butler of Tylight™.

Regardless of whether fossil dinosaur tracks in Western Australia are stolen, or fossil tracks elsewhere are legally (and well intentionally) collected, science can still be done on future finds of fossil tracks by seeking other ways of knowing them. These ways can still result in our knowing what animals made them and why, while also being aware that the beliefs of living descendants of indigenous people can be respected without unnecessary intrusion. This is what our current Western culture calls a “win-win scenario,” but I like to think it of it as honoring one another during our short time together here on this 4.6 billion-year-old earth. To quote the late American writer Kurt Vonnegut:

"Hello babies. Welcome to Earth. It's hot in the summer and cold in the winter. It's round and wet and crowded. On the outside, babies, you've got a hundred years here. There's only one rule that I know of, babies - "G*d damn it, you've got to be kind."


One of my favorite Australian bands, Yothu Yindi, with a short introduction by the lead singer - Mandawuy Yunupingu - about our relationship to the earth. And if you don’t like my preaching, that’s fine. There are lots of blogs out there about funny cats that really need reading.

5 comments:

  1. Dear Chiboogamoo! Wow--this entry is so entertaining and informative. You always surprise me with how much you know and then how you amplify the experiences I have with you in the field. I remember being stunned when we were looking at the Native American petroglyphs and being shocked that the dinosaur tracks beneath them had been removed. I felt like crying! I also know how much Adrienne Mayor's book, Fossil Legends of the First Americans really informed our understanding of how grave the situation was of removing these fossils from their site of origin.

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  2. excellent post!

    John Long's book The Dinosaur Dealers is one of my favourite (scary) books ever! I like how you emphasis the cultural value side of the fossil collecting issue here.

    Cheers!

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  3. Thanks for the positive comments, Traumador! I will have to read John Long's book - knew about some of his other ones, but somehow missed "The Dinosaur Dealers." Thanks!

    Cheers,

    Tony

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  4. I thought fossils can happen in China only, hard to believe that it happens in WA, too. They could have been the immigrants who committed this.

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  5. sorry..."I thought fossil stealing.."

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