WWD: Tyrannosaurus rex (Adult) (Patreon)

Here we move on to the sixth and final episode of this seminal series. The age of the dinosaurs draws to a close, a cosmic haymaker is on its way to bring an explosive end to the Mesozoic Era. So what other choice was there than to focus on Hell Creek, the locale with the most recognizable dinosaurs ever? And of those, they just could not resist making the main character the most recognizable dinosaur species of all.

King of the tyrant lizards. Over twelve metres long and up to ten metric tonnes in weight. Its five-foot long jaws exerted the strongest known bite of any land animal in this planet's history. It was one of the largest and most powerful carnivores ever known to have walked the Earth. Studies have indicated extraordinarily honed senses of vision, hearing, touch, and smell, and possibly even great intelligence, attributes which made it a highly efficient hunter of equally massive prey. No other land predator even close to T. rex's size was known to have coexisted with it, because it had an extended adolescent stage which allowed it to dominate mesopredatory niches as well higher trophic levels. This animal was the undisputed apex predator of Laramidia during the Late Maastrichtian epoch. 

That's all well and good, but I have to say WWD's depiction of the species is pretty hideous in numerous respects. Its snout is unnaturally blunt, the tail is way too short and thin, arms are too long, it seems to have no ischium, there's a weird frill at the back of its skull, neck is unnaturally narrow, and it walks on the very tips of disturbingly hoof-like toenails. None of this has to do with palaeontologists making any sort of new discoveries in the years since, it was as ugly then as it is now. Jurassic Park did a far better job with T. rex than WWD did five years later. It's truly baffling how badly they messed up this animal above all others.

In terms of science things that did get outdated, the episode makes a point of stating that females were bigger and meaner than males, which was an idea that was catching on at the time (you can see it in other dinosaur media around the time like The Lost World novel and When Dinosaurs Roamed America), due to a study finding an "egg canal" gap in the tail vertebrae of female crocodilians. The extremely robust "Sue" Tyrannosaurus specimen apparently had this gap in the tail vertebrae in the same location, leading to the idea that female Tyrannosaurus were bigger than males. However, both facts were in error, with a followup study failing to replicate the findings of the so-called "egg canal" gap in crocodilians, and the gap didn't exist in "Sue" regardless, rendering the idea inconclusive at best.

Tyrannosaurus was also much heavier than depicted, with the largest specimens within the range of 8-10 metric tonnes rather than the 5 metric tonnes stated, and even the smallest known adult individuals were closer to 7 tonnes. Part of this has to do with better understanding of the gastralia, or belly ribs, which are now known to have been placed considerably lower than traditionally depicted, giving T. rex a rather rotund and barrel-chested appearance, especially compared to giant theropods like Giganotosaurus or Spinosaurus, which are much narrower in cross-section. The skin texture of tyrannosaurs are also more well-known now; rather than the wrinkled, elephant skin-like texture shown, Tyrannosaurus was primarily covered in very minute, non-overlapping, bead-like scales. The scales would have been too small to see from a distance of more than a few feet away, although larger plate-like scales would have been present on the snout. There would also have been tarsus scales (like those of birds) present on its feet and lower legs.

The WWD Tyrannosaurus makes the design choice of giving it big brow ridges over each eye. This was an idea floating around at the time that the several bony knobs over the eye supported a single large ridge in life, although it was a controversial idea even back then, and I don't think it has many supporters these days due to lack of any evidence supporting it beyond saying "it could be possible".

Also, although it's universally depicted, whether or not Tyrannosaurus could actually roar is unknown. Until recently, the probability would have been considered very low due to lack of evidence, limiting them to bellows and growls like crocodilians, but a study a few months back reported on a syrinx (the structure birds use to make sounds) being found in an ankylosaur, so it's possible. Still though, you shouldn't be roaring while you're hunting, that totally defeats the point of an ambush (at least Prehistoric Planet showed a hadrosaur hunt with attention to finesse and stealth).