7/26/2022
I recently made some small changes on chapters 1 and 2.
I had read on a couple different websites that Radiodactylus had a five-foot wingspan, but I was never able to verify that number. It seemed like the same websites were referencing each other in a circle. Since I couldn’t find any citation, I contacted Dr. Dale A. Winkler, who’s the point person for the Shuler Museum where SMU 72574 is kept.
He provided comparable wingspans of other pterosaurs with a similarly-sized humerus and estimated Radiodactylus’ wingspan at ten feet.
After reading Dr. Winkler’s research papers for close to a year trying to prepare for this story, when I say I was excited to get his email back . . . imagine a little kid who loves firetrucks meeting a fireman. There may or may not have been some jumping up and down.
You know. In an aloof, professional way.
Anyway. He was super nice, and I’m so grateful he took the time to give me the answers I needed. The other thing that had me bouncing in my seat was that Radiodactylus’ wingspan was double what I originally thought.
With the information Dr. Winkler gave me on wingspan, I sat down to try and plug that wingspan into the proportions of a fairly typical Azhdarchid to try and get a sense of height. It didn’t need to be exact, just ballpark.
I did some actual math for this—cue applause—where I calculated ratios like this:
X Wingspan of Example Azhdarchid: Y Feature of Example Azhdarchid X = 10 foot Wingspan of Radiodactylus: Z Height of Radiodactylus
However, I haven’t done real math since I graduated high school, so I didn’t totally trust my process. So after I got those numbers I tore up a Zhejiangopterus skeleton drawn by Mark Witton, made a crude digital ruler, and created this masterpiece to check my work.
On a funny, stupid note, the first time I did this I wrote down the length of one wing as ten feet, not five—so the entire time I was sitting in front of my computer like “Criminy, this thing must stand more than eight feet tall. It’s taller than a refrigerator. I’m going to have to totally rewrite chapters 1-3 because there’s no way Nuke would fit in the paleo lab.”
And then I walked away for about ten seconds and went—“wait, did I say ten feet or five?”
So it turns out, when you base pretty average Azhdarchid proportions around a ten-foot wingspan, Nuke would stand about two and a half feet at the shoulder. If Radiodactylus is fairly long-necked, and if he held his neck straight up, that would add up to about five feet. I assume Nuke carries his head a bit lower, so we’ll say 4.5, about eye-level with Cecelia. His skull would also be about two and a half feet long.
Luckily, he stands just about that tall in the original version of the chapter. I think I overestimated the length of his leg with his wing finger folded up the first time I wrote it.
After this I got out a tape measure so I could really appreciate Radiodactylus’ size. Ten feet is a lot. That’s like two picnic tables pushed together, about the same wingspan as a California Condor.
I ended up making the following changes:
Chapter 1
-“long, slender neck” is changed to “long, straight neck”.
-Corrected the most blatant error, where Cecelia directly says that “Radiodactylus unfolded its switchblade wings to their full five-foot span, as wide as a heron.” It is now ten feet with no modern bird comparison.
Chapter 2
-“swan neck” changed to “tall neck”. It seems azhdarchoids probably had pretty stiff necks.