Christ Packham's T-Rex Christmas Special - Jan 5

Let us talk about the T-Rex Christmas special with Chris Packham. What can be said about it?

…No offence to Mr. Packham, but his special did not invent the bicycle or the wheel – at least two thirds of it, (maybe more), is a rehash of earlier dinosaur specials. The bite power of the Tyrannosaurus Rex, its’ speed, strength, sight and other senses were discussed back in 2005 on ‘The Truth about Killer Dinosaurs (2005) with Bill Oddie; (for an all-American dinosaur Tyrannosaurus is certainly popular across the pond); and the feathers, coloration and growth patterns were discussed on ‘Dinosaurs Decoded’ (2009) with Jack Horner. In other words, the image of Tyrannosaurus Rex has been ‘updated’ from its’ first-half-of-the-20^th-century depiction for years by now, and did this Christmas special -2017-2018 – give it anything new?

The most obvious are the vocalizations: apparently, T-Rex did not roar, but rather bellowed, as the modern Eurasian bittern does. The latter, if people don’t know, is a relative of herons and egrets, but while herons tend to be big and noticeable, (especially in flight), and egrets are often colorful, the bittern is small, short-legged even, and is covered in cryptic-colored plumage, one that blends the bittern with its surroundings: small ponds and lakes overgrown with rushes, cattails, other similar plants. When it stands still and stretches itself upwards, (there are photos of this sort of thing), bitterns are often very hard to spot, period.

However, they are also loud; the aforementioned Eurasian bittern can bellow as loudly as a bull, which is why in parts of east Europe and European Russia it is called ‘the water bull’. Thus, is Tyrannosaurus Rex had behaved as the modern bittern does – a shy, retiring, nocturnal creature with deadly hunting skills, (though more like a tiger than a lion), and a very loud voice. That would be cool, (and hey, Michael Crichton had written in Jurassic Park the novel that ‘Rexy has sensitive skin and sunburns easily’, so there!), but it probably would not be true. Or would it?

The last part was the social life of Tyrannosaurus Rex. Again, it was discussed on television, for example in the 3^rd episode of ‘Planet Dinosaur’ (2011), when daspletosaurs, cousins of tyrannosaurs, (and contemporaries of albertosaurs mentioned in Packham’s special), were depicted. And also – in the 5^th episode of the 2011 series, which focused not on tyrannosaurs, but on carnosaurs, in particular Mapusaurus, which supposedly also lived in family groups. But-

But the discussions about the social lives of theropods began a while ago; for example, in ‘The Complete Guide to Prehistoric Life’ (2006), a companion book to ‘Impossible Pictures’ ‘Walking with…’ series, the Giganotosaurus entry discussed the discovery of several Giganotosaurus skeletons found together, thus raising the possibility that they were a pack that hunted together…or a group of strangers that died in the same spot by an accident, (say – a flash flood).

When discussing the social lives of theropod dinosaurs, the following must be kept in mind. On one hand, these animals were like the modern crocodiles and co. – not exactly social creatures, but creatures that could gather together to feed. For example, the modern Nile crocodiles do not form social bonds as their neighbours the African lions do, but they do feed together, and tolerate one another during these times.

The same goes for the modern dinosaurs – the birds, especially birds of prey. They do not hunt in packs as mammals do (lions & spotted hyenas, grey wolves & wild dogs, killer whales, etc.). They hunt alone, regardless of whether we are talking about a goshawk, a kestrel, or a peregrine-

Pause. Memory helpfully assists: in modern times, Mother Nature has brought forth a so-called Harris’s hawk, a medium to large-sized bird of prey, which might be the only bird of prey that hunts in packs, just as the lions do. A typical Harris’s hawk family consists of a dominant female, her mate, and their young from the previous years, which help not only with hunting, (this bird feeds on smaller birds, lizards, small mammals and large insects), but with raising the next generation as well. Amphibians, reptiles and most other birds do not do that. Thus, it is quite possible that tyrannosaurs, (and carnosaurs, abelisaurs, therizinosaurs, etc.), also behaved so, as modern Harris’s hawks do. Only…

Only Harris’s hawks are exceptions to the rule, not the rule. Most other birds don’t do that, and young birds of many species (owls, diurnal birds of prey, some wading birds, etc.) actually eat each other – inner-species cannibalism, you see – so the odds that the same went for their relatives, the extinct theropod dinosaurs. The modern crocodiles, alligators and co. also have the same problem, as do some of the other modern reptiles. Odds that that most of the theropod dinosaurs behaved like that too.

…And yes, there was at least one different group – the therezinosaurs, because this group of theropods became…herbivores instead, so they probably simply could not eat meat, (aside from an occasion insect, snail or tree frog that they would swallow with foliage). More importantly, they are mentioned here because they were highly derived specialists – as were the tyrannosaurs.

To clarify, this brings us to the issue of Rexy’s metamorphosis: back in 2009, Horner explained just how much the tyrannosaurs changed as they aged. (Ditto for Triceratops’ and etc.). This brings us to ‘Jurassic Fight Club’ (2008) and the Nanotyrannus. Nanotyrannus (‘dwarf tyrant’) is a potentially dubious genus of tyrannosaurs, known only from two or three specimens, and which just may be juvenile Tyrannosaurus’. The problem is that either way the evidence is inconclusive, Nanotyrannus can be just a juvenile T-Rex, or it might be a separate genus, so this was probably why Mr. Packham did not mention it by name, just slid past it, mentioning that juvenile tyrannosaurs were different from the adults, but the front limbs of these dinosaurs remained underdeveloped – and this is worth discussing, but just like the therizinosaurs, the tyrannosaurs were derived specialists.

When compared to carnosaurs, tyrannosaurs show much smaller front legs, much bigger and stronger head and jaws, and overall a much more robust skeleton. Whereas carnosaurs remained unchanged from the Jurassic, just got somewhat bigger, tyrannosaurs got a lot bigger and proportionally stronger: they were better fighters and killers out of the two. Why? Because they evolved. Certainly, there were some differences between the Jurassic carnosaurs like Allosaurus and Sinraptor, (no relation to the ‘true’ raptors of the Cretaceous, BTW), and their Cretaceous descendants, (Carcharodontosaurus, Giganotosaurus, Mapusaurus, etc.), but the differences between the last of the tyrannosaurs, (including T-Rex itself and its Asian counterpart Tarbosaurus), and the first ones, like the Dilong, are much bigger.

Dilong is the oldest tyrannosaur currently known to science. It was a fairly small dinosaur, about 1.5 m in length, generic looking, complete with long forelimbs, armed with three fingers. Eotyrannus was bigger – about 4.5 m long – but it also had typical three-fingered forearms of theropods. Sometime during the Cretaceous tyrannosaurs began to specialize into killing machines, and unlike the four-legged mammals that evolved jaws and/or claws, they simply went for the jaws.

Ditto for abelisaurs, distant descendants of the Jurassic Ceratosaurus. They were not very close relatives of the tyrannosaurs, but if you would put an abelisaur, (say, a Majungasaurus), next to a tyrannosaur, (for example, a Daspletosaurus), the similarities created by parallel evolution would be obvious: sturdy hind legs, tiny front limbs, long tail, powerful jaws, head, and neck muscles. A carnosaur, like Carcharodonotosaurus, acted like a shark, inflicting many small wounds, trying to bleed its prey to death, or choosing something that is initially smaller than it was, like a juvenile sauropod. An abelisaur, like Rugops, would wrestle its prey to death, even it is the same juvenile sauropod, because it could not be a ‘land shark’, the carnosaurs already took over the niche.

Among mammals, not all carnivores are specialists; some of them, including most of the bears, are omnivores instead. But none of the carnivorous reptiles can eat plants, and neither can most of carnivorous birds. They are derived specialists, and Tyrannosaurus Rex was their king.

Anything else is left? Not really. BBC’s T-Rex special for Christmas of 2017-18 was…okay. It was not good, it was not bad, it was safe, and when Tyrannosaurus got compared to a Eurasian bittern, it was actually hilarious.

…See you all next time, then!