If you’ve been viewing my video reviews, you may have noticed I’ve been re-arranging the dinosaurs on my shelf with each review. I’ve been trying to mix it up with each review, and if at all possible, theme the models on display after the featured book. The book in question this time was “Boy, Were We Wrong About Dinosaurs!”, and here I’ve displayed figures representing ideas both completely outdated, and more modern.
I’ll start with the flashiest first. On the right we have the Spinosaurus I grew up with. With a spotty fossil record, the standard interpretation was that of a reasonably large, generic, vaguely Allosaurus-like predator with a sail tacked onto its back (one of the few unique features it was known to have possessed). With further discoveries, Spinosaurus proved more unique than previously suspected. It was now clear it possessed a crocodile-like snout, and its proportions suggested it was likely the longest theropod dinosaur known. Incidentally, the version depicted on the left may also now be out of date, since even further discoveries have suggested it may have possessed oddly short, stocky legs compared to other theropods.
Next up: feathered dinosaurs! On the right we have the classic Carnegie Deinonychus pack; buck-naked, and not too dissimilar from Bob Bakker’s classic drawing. Now, it was the skeletal structure of Deinonychus that led to the idea that birds might be related to dinosaurs, and since its discovery, that connection has only seen further support. We now know all so-called “raptor” type dinosaurs possessed some form of feathery covering. Some, like the Microraptor descending from the tree, could even glide! (It’s important to note that Microraptor is closely related to Velociraptor, and while both are in turn closely related to birds, they sit firmly outside the family of true birds.)
Any fan of pterosaurs knows Quetzalcoatlus as the largest flying creature of all time, but for a certain period, that ALL that most people really knew about it. It’s discoverer has infamously sat on the most complete skeleton for over 40 years without allowing anyone access to it, and a better understanding of its life appearance has only recently begun to trickle out. On the right, we have a supposed “Quetzalcoatlus” that’s clearly just a female Pteranodon, accompanied by a more modern take on the left. Note the large skull and very long neck, probably its two most distinctive features. As an aside (to explain the baby dinosaur in its mouth), Quetzalcoatlus and its kin are thought to have spent much of their time on the ground, preying small animals like modern storks, as opposed to catching fish on the wing like modern seabirds, traditionally the go-to analogues for all pterosaurs.
Next up we have the therezinosaurs, which have a long, complicated history of study. Therezinosaurus itself is known only from its large arms tipped with enormous claws, a find which caused much speculation among dinosaur experts. Not long after its discovery, scientists began discovering creatures that seemed to belong to a new family of dinosaurs they labeled “segnosaurs”, with a weird grab-bag of skeletal features. One of the most popular hypotheses about them suggested they were late-surviving prosauropods like the Plateosaurus on the right. Later, better preserved finds showed that “segnosaurs” and Therezinosaurus belonged to the same clan, which was now renamed “therezinosaurs” and placed within the meat-eating theropod family, despite the fact that therezinosaurs appear to have been herbivorous. As a final note, the smaller animal in this picture, Beipiaosaurus, was discovered to have possessed a coat of simple feathers, which of course means its relatives likely did as well, including the giant Therezinosaurus.
The final image features Tenontosaurus and some presumed relatives. On the right, we have a family of Hypsilophodon, the namesake of a one-time large family of small plant-eating dinosaurs, the hypsilophodonts. Early on, Tenontosaurus was thought to be the largest member of this group. However, later research revealed most so-called hypsilophodonts were not actually that closely related, and the group was split apart. Tenontosaurus is now thought to be a smaller relative of the famous Iguanodon, standing to the left of the picture. Interesting side-note, an abundance of Deinonychus teeth surrounding a skeleton of Tenontosaurus was once suggested to be evidence of pack behavior in the “raptor” dinosaurs, though later researchers have pointed out there’s no particular reason to think this. Perhaps multiple loner Deinonychus simply converged on a deceased individual, or maybe the teeth even washed in from somewhere else. It’s hard to say anything definitive.
And that’s what on the Dino Dad’s shelf! I hope you found this little diversion interesting. I may make this a regular feature following each video book review if I can find something substantial to say about my little arrangements. In any case, keep a lookout for our next book review, coming soon!