“Dinosaur Island” sounds like a cheap Jurassic Park rip-off, but it was a very accurate title for the presentation given last night by Professor Scott Sampson, one of the international guests for this year’s Science Week tour. Being in the upstairs function room at the Redback Brewery brought back fond memories of science activity; it’s been used as a venue by Science in the Pub, Science in Public and the Australian Science Communicators.
Scott covered a several angles of dinosaurology (you’ll be hearing more of this word from me soon), first offering a brief overview of dinosaur knowledge and how our picture of these animals has drastically changed. As you probably know dinosaurs were originally depicted as slow and dull – in both the mental and physical senses. In his words, though, dinosaurs became supercharged in a cultural nanosecond, and it’s all the raptor’s fault. That’s raptor in the “raptor-like dinosaur” sense, since he doesn’t blame Jurassic Park; rather it was the discovery of Deinonychus which originally led some palaeontologists to speculate a link between birds and dinosaurs, and when that become the majority opinion in the 1990s with the discovery of feathered dinosaurs, everything was turned on its head, graphically illustrated by the contrast between the old-school, dog-like dinosaurs in images by artists like Charles R. Knight and Heinrich Harder and those by recent dino illustrators like Greg Paul. Colour, movement, feathers…it’s all there.
From this beginning Scott made his way to his own research, mostly on dinosaurs of western North America. Around 75 million years ago what we know as North America was split into three or four pieces, and the westernmost part was a long, thin strip of coastal plains, separated from the eastern Americas by a narrow seaway – Dinosaur Island indeed! When plate tectonics allowed continental drift to be accepted by mainstream geology in the 1960s, it was no longer a mystery how dinosaurs had managed to spread across the whole, but in estern America the fossils presented a new mystery. The species found in Utah and New Mexico (in the south) were different to those in Alberta and Montana (in the north). Not only were there lots of different species, but there were lots of dinosaurs – in his sites in Utah, Scott revealed that you couldn’t walk for 15 minutes without spotting the telltale signs of dinosaur bones; he also regularly finds “bone beds” containing tens or even hundreds of specimens that died together, evidence of massive herding behaviour in herbivorous dinosaurs.
This is weird; as Scott says, there’s only one species of elephant in Africa, a much bigger area than Dinosaur Island. So how could this sliver of North America support so many individuals of so many species? Several ideas were put forth by the resident audience expert, who was of course a ten year old boy (and ginger too, which gave me a twinge of pride). Was there a huge abundance of food to support them? Did they have slower metabolisms, and require less food than modern animals? Was it easy when there weren’t human beings around to stuff things up? Or did they not really live all at the same time?
That’s what Scott set out to determine with his digs in the Grand Staircase Escalante National Monument, and he shared lots of details about how the dig is run. His “rag-tag fugitive fleet” of volunteers and students were centre-stage; as in astronomy, Scott stressed that palaeontology would get nowhere fast without these mostly unpaid workers. Not only do they spend hours in the field looking for fossils and uncovering them,Â they get used as pack animals transporting them out of the inhospitable terrain – thought the biggest are airlifted by helicopter – but also spend up to two years preparing them for serious study. (He later revealed that his favourite scene in Jurassic Park is the scene at the start where they uncover a whole Velociraptor skeleton in a couple of minutes, which makes him laugh. Scott loves Jurassic Park, since it’s entertainment, but has a beef with Walking With Dinosaurs and its ilk, who present their conjecture about dinosaurs as fact.)
At Grand Staircase Scott’s team has found a huge variety of ceratopsian, duck billed, armoured and carnivorous dinosaurs. It seems these species really did co-exist, and that there was both more vegetation to support them, and perhaps they had slower metabolisms. Crocodiles, after all, can go without food for up to two months, but top mammalian predators can’t hope to do that. (Mammals, he joked, are the SUVs of the animal world, burning up as much energy as they can get their hands on, while reptiles are more like a Prius.) His own theory, which he admits is still contoversial, is that dinosaurs occupied a “Goldilocks” state – their bodies were not too cold-blooded nor too warm-bloodied, but just at the right metabolic rate in the middle, making them quite unlike anything alive today.
Scott wound up the prepared bit of his talk with his opinions of why dinosaurs are important to science. His basic point was that they’re a great hook to start conversations about immediately relevant topics like global warming. An understanding of climate changes brought about the asteroid which probably wiped them out (correctly identified as falling in the Gulf of Mexico by our audience expert) was also used as evidence for the destructive power of a nuclear winter, leading to the (relative) end of the cold war, so as Scott says, dinosaurs have saved the earth!
Scott left time for a question and answer session, and as you might expect, he knows his stuff. None of the questions phased him, and he answered them all directly. No doubt his upcoming book, Dinosaur Odyssey, will really live up to his claim: “it’s the first time a palaeontologist of my generation has really tried to set down the current state of knowledge about dinosaurs.”