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-20th-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 3rd
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 5th 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!
