Secret Base Reviews: Azhdarchidae, the flying death giraffes

The wandering albatross has the longest wingspan of any modern bird. The largest known specimen measured a little over 12′ from wingtip to wingtip, which makes it a really really really big bird. That’s almost the length of a small car, taller than a basketball hoop, and about as tall as three Ryan Nannis sitting on one another’s shoulders. Your takeaway from this paragraph should be that the wandering albatross, which skims its way over the storm-tossed Southern Ocean, is a large-ass bird.

Your takeaway from this paragraph should be that there used to exist things — monstrous things — that made wanderers look like god damn dragonflies. In the late Cretaceous, before the asteroid impact that wiped out most of the dinosaurs, the azhdarchids ruled the sky. Here is a list of some of the larger species, with their estimated wingspans:

• Quetzalcoatlus (36-39′)
• Hatzegopteryx (33-39′)
• Arambourgiania (39-43′)

I want to stress that these are estimates. Pterosaur fossils are relatively rare. One reason for this is that their bones are so lightweight that they’re rather difficult to preserve, so anatomy is frequently inferred from incomplete skeletons. For instance, Arambourgiania, which is perhaps the largest creature ever to fly, is only known from a handful of vertebrae.

That said, we can be pretty confident that we have the scale about right. We have enough of Quetzalcoatlus to pin it down at, oh, definitely small-aircraft-sized. Which is FUCKING HUGE.

Azhdarchids were known when I was a kid, although Quetzalcoatlus was the only one to have flapped its way into the popular dinosaur books I consumed. Back then, the idea was that it was a far-roaming scavenger, sort of an analogue to the California condor. I think this was mostly because nobody could really imagine what else something that big might do. The biggest modern land bird that spends most of its time in the air floats around looking for carrion, so why not make Quetzalcoatlus do that too? Seems fine.

My childhood conception of the azhdarchids, then, was as monstrous vultures, soaring over the plains looking for dinosaur carcasses to eat. Which, honestly, was a little bit boring. GOOD THING THAT’S CHANGED.

A couple decades later, it’s becoming more clear than ever that the biggest azhdarchids spent much of their time on the ground, not as scavengers but as predators. How do we know this? The biggest hint is their forearms, which are beefy enough to support their weight for long periods of time, and indeed fossil trackways have been found showing that giant pterosaurs were very comfortable walking about on all fours. Another hint is the shape of their jaw. Modern vultures have hooked beaks for tearing carcasses. Quetzalcoatlus does not. Its jaw is basically shaped like a giant sword, which can be used for stabbing movements or to grab smaller prey.

I should point out that Quetzalcoatlus’s head was significantly longer than you are tall. That’s just a thing you should know.

So what the hell would one of these things look like? The biggest azhdarchids were flying critters the size of small aircraft which spent their time ambling around on the ground looking for smaller critters to messily devour. There’s no modern-day version of this at anything like the same scale. Instead, we’re going to have to turn to something much friendlier:

Cameron Spencer/Getty Images

This is a giraffe, which I don’t know why I’m telling you, since you know what a giraffe looks like. By sheer happenstance, the Quetzalcoatlus, Arambourgiania and pals were pretty much exactly giraffe-sized when they were on the ground in quadruped mode. Their shoulders right in right about the same place and their necks were suitably giraffe-ish that you can pretty easily superimpose an azhdarchid over our tall mottled frens.

We need to make some modifications, of course:

Getty Images

(Hey! I said consummate ‘v’s!) Anyway, that is an artist’s, uh, impression of Quetzalcoatlus, which would have been one of the most terrifying predators to encounter in late-Cretaceous North America. It would have been quite capable of devouring you or me in one horrible gulp, and I think it would have really enjoyed the whole process too. It weighed 500 lbs or so, and it could fly. Truly, we are speaking of a demonic entity.

But that is not all! Because while Quetzalcoatlus was cool and scary and all that good stuff, it had nothing on its European cousin Hatzegopteryx.

At the time, much of Europe existed as a subtropical archipelago. If you were paying attention in biology class, you’ll remember that island ecology gets pretty wild. Even in modernity, islands give us Komodo dragons, meter-long crabs and vampiric songbirds. Mesazoic islands, meanwhile, give us ... this:

Unlike Quetzalcoatlus, which shared its habitat with big meat-eating dinosaurs, Hatzegopteryx ruled both land and sky. Its ability to fly gave it a much greater range than an equivalently-sized terrestrial animal, apparently allowing it to outcompete the big therapods and become an apex predator.

It was built like one too. Its head and neck were much more robust than other azhdarchids, allowing it to kill and eat correspondingly larger prey, including some fairly good-size dinosaurs. Since we’ve already established that Quetzalcoatlus et al. are, in essence, demonic beast from the very bowels of hell, I fear we’re about to hit the great metaphor wall with Hatzegopteryx.

Suffice it to say that the flying death giraffes that ate dinosaurs had a big brother. I think it’s very cool that these fuckers once lived, but I am also extremely glad that they’re not around anymore. Thank goodness for asteroids.

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