PAWPAWSAURUS

Pawpawsaurus is the first—and so far, only—member of Nodosauridae, the lesser-armoured branch of Ankylosauria, known to possess the bony eyelids typically reserved for ankylosaurids, their heavily fortified cousins. Unfortunately, it may be synonymous with Texasetes, another nodosaurid from the same area, and if this proves to be the case, Yuong-Nam Lee is going to be mightily disappointed. Although he discovered Pawpawsaurus three years before Texasetes, his official description arrived a full year later, so the former name would be invalid. Nevertheless, the pair are currently treated as separate species, and it's Pawpawsaurus that gets all the scientific love.

In 2016, researchers at Austin's University of Texas blasted Pawpawsaurus with computed tomography (CT) and digitally rebuilt its skull in 3D, offering the first-ever glimpse into the intricacies of a nodosaurid brain. They found that nodosaurids, unlike their ankylosaurid relatives, lacked a flocculus—a structure in the brain that helped the likes of Ankylosaurus balance while swinging their clubbed tail, which wasn't such a problem for Pawpawsaurus since—like most nodosaurids—they lacked a clubbed tail too. Compared to ankylosaurids, nodosaurids also had a reduced nasal cavity, a smaller olfactory bulb (the part of the brain that deals with scent) and a more modestly-sized lagena (a portion of the inner ear that interprets sound). But this is no cause for shame.

Although accused of being cumbersome windbags, the most advanced ankylosaurids had great balance and hearing, as well as an incredible sense of smell thanks to their intricate nasal labyrinths. Yet nodosaurids in general—and Pawpawsaurus in particular—also had keen senses. In fact, they outperformed most predatory dinosaurs in this regard, with only allosauroids (like Allosaurus) and tyrannosaurids (such as Tyrannosaurus) better equipped for smelling and hearing.