DRAGON FILES
Could Game Of Thrones’ dragons exist? We look at their biology with Paolo Viscardi, curator of zoology at the National Museum of Ireland
THEY’RE NOT REALLY DRAGONS
“their morphology is not actually that of a dragon, it’s that of a wyvern – dragons have four legs and a pair of wings or sometimes no wings, whereas a wyvern has a pair of hind legs and then a pair of wings, like a bat. It’s a much more sensible design in terms of evolution because you wouldn’t expect additional limbs [like wings] to appear out of nowhere.”
FLYING
“the dragons aren’t too much bigger than the biggest known flying animal, which would be the Quetzalcoatlus, a pterosaur that had a wingspan of around 11 metres – the size of a small plane. But one of the big issues I have with something that size is that just supporting your own weight in the air is a lot of effort for bones. the Quetzalcoatlus would probably have weighed up to 250 kilos and they were slightly built, with hollow bones – they didn’t have a big long muscular tail or a big load of huge teeth and extensive horns sticking out all over the face. also, with the dragons in Game Of Thrones, I’d expect them to have a bigger chest for the flight muscles they would need to power the groundstroke of the wings.”
THRIVING IN EXTREME HEAT
“I can’t think of many biological things where fire is great – though there are quite a lot of seeds in australia or parts of the states that respond when they’ve been through some kind of brush fire. and then there’s tardigrades which can survive very high or low temperatures. they’re basically almost indestructible! But when you get to the fairly complex things like vertebrates, most of them can’t really deal with very high temperatures.”
BODY ARMOUR
“It’s not unusual for grounddwelling or semi-aquatic reptiles to have a bit of armour on them, but obviously as soon as you get into the air that’s extra weight. the general trend is you don’t need to be heavily armoured if you’re not eaten by other things, or not fighting against other things. other than that it’s kind of pointless being that heavily armoured if you’re an apex predator.”
BREATHING FIRE
“[Having two tubes of chemicals that react to combust] is quite an interesting way of approaching the whole fire breathing thing. Bombardier beetles have two little glands containing a couple of chemicals that react. It doesn’t actually burn as such but it gets very hot very quickly, and it then uses that to power a small explosion where it squirts scalding hot liquid at things that are attacking it. to keep the fire going, you’d then need a large volume of fuel, and herein lies part of the issue. If you’re going to have fire breathing, you need a fuel reservoir to make that happen, though it’s not so bad if you’re dealing with a liquid that then gets vaporised, because you can squeeze a liquid into a much smaller space than [the equivalent] vapour.”