Dinosaurs: the dirty details

Tyrannosaurus Rex in scene from film 'Jurassic Park'.
A scene from Jurassic Park (1993), directed by Steven Spielberg, showing Dr. Ian Malcolm diverting the T-Rex’s attention away from the car with John Hammond’s grandchildren in it.

Most of us will be familiar with this scene. A fair amount of us were likely obsessed with dinosaurs back when we were (little) terrors ourselves. For a lucky few of us, our sensitive, impressionable, monster-hugging age more or less coincided with the release of this film. I was one such kid. And for me, the fascination never went away. I’m sure I’m not the only one.

I reckon most of the people reading this post must at least have had a mild ‘Ooh, dinosaurs, cool, let’s check it out!’ feeling, so I’m hoping my upcoming ramble about some lesser known facts and common misconceptions regarding dinosaurs won’t bore all of you to death.

However, before tumbling back in time into the Mesozoic, I feel a pit stop at the question of relevance is needed. How can we justify, as a scientifically oriented modern world looking to the future, spending time and money digging up these magnificent bastards who have been dead for a very long time and piecing together minute details about their lives? It can’t just be so that we can make films such as Jurassic Park and sell loads of dinosaur toys to googly-eyed children, can it? (Although I guess it’s naïve to be naïve where it concerns capitalism…)

First off, at a very basic level, seeking any kind of knowledge can be beneficial – it would be very misguided indeed to suppose that we can predict whether studying certain things will fail to yield any kind of useful results, and to equate ‘progress’ for mankind only with studies focused on our modern world or our future.

More concretely, the study of dinosaurs is a field in which geology, science, and biology are constantly developed and tested. The boundaries of what’s possible were shifted, for instance when Dr. Mary Schweitzer managed to extract soft tissue from a 68 million year old T-Rex fossil (a girl named Sue). Also, new knowledge about the geological history of our planet is gathered while digging into rock formations. Most compelling are perhaps the new insights into evolution, nature, the adaptability of species and their relation to their environment. I mean, dinosaurs roamed the earth for around 163 million years. Try comparing that to our genus of Homo, which is less than 3 million years old. And to be honest, at the rate at which we are destroying our planet and each other, I dare say we won’t quite come close to giving the dinosaurs a run for their money. I wouldn’t want to try and outrun a T-Rex, anyway.

Lastly, the Ross Gellars of this world also need jobs. I think having people who creatively reproduce the sounds a velociraptor could have made can only be an asset to our species.

Now, with that out of the way, let’s get down to business. First off, let’s gnaw away a bit at the base of the pyramid. The name we have been using for these creatures ever since the birth of proper dinosaur palaeontology in the early nineteenth century, Dinosauria, from the Greek deino (‘terrible’) and sauros (‘lizard’), is inaccurate. The size of our heads ever-increasing, in the course of the twentieth century we realised that dinosaurs aren’t lizards at all. They are both individual, specific groups of reptiles; brothers, if you will. It is, of course, a bit late in the day to go back and change all the names.

But wait a minute, reptiles are mostly ‘cold-blooded’ (ectothermic). Imagine a sluggish snake slowly slithering into the sunlight to warm up. In the early years of dino studies, dinosaurs were thought to have been the same. Luckily, as we now know, not nearly all dinosaurs were like this. Although large dinosaurs like the sauropods (Diplodocus, Brachiosaurus etc) most likely edged closer to being ectothermic, with their walnut-sized brains matching their bodies in speed, a host of other groups may have had mixed metabolisms, perhaps shifting from being predominantly endothermic (‘warm-blooded’) as juveniles to more ectothermic as adults. The group that eventually evolved into birds even became fully endothermic somewhere along the way; imagine hyperactive, bouncy tooth-machines with varying amounts of feathers. Wait – birds?

Yep, bird is the word. When everyone talks about the ‘dinosaurs going extinct 65 million years ago,’ they’re not entirely sensitive to the nuances; not all dinosaurs went extinct. Birds don’t come from dinosaurs, birds are dinosaurs. They share more characteristics with other members of the group Dinosauria than with any other group, and they were versatile and adaptable enough to survive the asteroid impact and the ensuing hell on earth. So if you want to be snobbishly accurate, you’ll say that all the non-avian dinosaurs went extinct all those years ago, and that only the avian dinosaurs, aka the birds, survived. They evolved within the group known as maniraptora; mostly ‘raptor-like’ dinos that had long arms with three-fingered hands, hollow bones, and wishbones. And a fair amount of them developed feathers. Flight developed at some point in this group of maniraptora, though it is uncertain when exactly. Deinonychus, the real inspiration for Jurassic Park’s Velociraptors (actual Velociraptors were a lot smaller), must have resembled a very scary, toothy, fluffy, oversized, and probably flightless chicken. Sadly, however hard I try, I can’t get myself to consider feathered dinosaurs scarier or cooler than the ‘naked’ versions – Jurassic Park’s representation of the raptors will always have a place in my heart.

What is even worse for the public image of dinosaurs: some members of the Tyrannosauroidae superfamily (which, as I’m sure will surprise you greatly, host the Tyrannosaurus family, too) were apparently also covered in down or even proper feathers. The best example is Yutyrannus, T-rex’s slightly smaller (at approx. 9 meters in length compared to T-Rex’s 12 meters) Chinese cousin, who had feathers on various parts of its body. As you can imagine, this opens up a whole can of worms regarding which dinosaurs were feathered and which ones weren’t – but I don’t have space to dig into that in this post.

After all this disheartening talk, I’ve got to end with a small section on the world’s most famous dinosaur: the king, the terrifying Tyrannosaurus Rex. First off, there is no evidence for T-Rex being feathered. Phew. Also, that whole thing they’ve got going in Jurassic Park where the T-Rex can’t see you if you don’t move is – if you hadn’t guessed it yet – very very creative film-making indeed; there is no reason at all to assume that such a loophole existed in real Mesozoic life. If you ever encounter a T-Rex, don’t freeze. Run. However, this Elvis amongst predators was not actually the biggest carnivore one could bump into. Spinosaurus, the weirdo with the huge crest on his back playing catch with the satellite phone in Jurassic Park 3, gave T-Rex a run for its prehistoric money. Giganotosaurus and Carcharodontosaurus (named for the strong resemblance of its teeth to that of the great white shark) are also known to have been slightly larger than T-Rex. In my opinion, this doesn’t make T-Rex any less cool; it was hugely successful and widely represented, with T-Rex fossils being found in a large variety of rock formations dated between 68 and 66 million years ago. Despite living way at the end of the Dinosaur age, the T-Rex takes up a dominating position in our imagination when it comes to these magnificent creatures. Kings indeed.

So much for the past; what about the future? The latest film in the Jurassic Park series, Jurassic World (2015), envisions the dino theme park up and running ‘properly’ and catering to an increasingly hard-to-awe audience. However, the method of extracting dino dna from a Mesozoic mosquito wouldn’t quite hold up in real life, and despite soft tissue being extracted from a T-Rex, finding actual dna in something so old is highly unlikely – let alone completing the sequence and actually cloning a dinosaur. Also, one would hope the Jurassic Park films would have deterred us enough from trying something so horribly doomed to fail (how arrogant could we get as a species… seriously).

Well, how arrogant, indeed. Scientists are already working on cloning a woolly mammoth after finding decently preserved dna in the permafrost. (See, for instance, this article: http://www.huffingtonpost.com/2014/11/24/clone-woolly-mammoth-buttercup_n_6211388.html). I find this quite shocking. In the original Jurassic Park, Dr. Ian Malcolm sees this atrocity for what it is when he speaks to John Hammond about his revival of the dinosaurs: “(…) Your scientists were so preoccupied with whether or not they could that they didn’t stop to think if they should.” Dress up warmly, guys, there are scary times ahead.

 

 

For further reading see, for instance, D. Fastovsky and D. Weishampel, Dinosaurs. A Concise Natural History (Cambridge University Press 2009).

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