Kess73 wrote: »
Cannot be the only one that thought of Phil Currie straight away?
Adam Khor wrote: »
There's between 12 and 15 tyrannosaurid genera currently described, and they span a considerably time period (from around 80 to 66 million years), yet their basic body plan changes practically nothing in all that time. So you have the oldest tyrannosaurid known from good remains, Lythronax:
looking almost exactly as the latest tyrannosaurids such as Tarbosaurus and Tyrannosaurus:
I think this is a case of "if it's not broken don´t fix it". Tyrannosaurids were perfectly adapted to what they were doing, so maybe if they hadn´t gone extinct at the end of the Cretaceous, and as long as there were large prey to sustain them, chances are they would have remained pretty much the same for a very long time, like crocodiles, perhaps with outliers here and then adapted to alternate prey (fish-eating tyrannosaur?) or environment (island dwelling, mini-tyrannosaurs?)
The body mass of RSM P2523.8 is
thus estimated to be ~8,870 kgs (+/- 25%).
exceeds all T. rex specimens that have been previously categorized as robust (Larson, 2008b).
However, in many length measurements (proximodistal femoral, tibial and jaw length) RSM
P2523.8 is exceeded by some individuals previously categorized as gracile (Larson, 2008b).
Whether or not a robust/gracile dichotomy exists among T. rex, these comparisons indicate that
RSM P2523.8 was a large and robustly-proportioned individual, but likely with a shorter total
hip-height and snout-vent length than other known specimens showing more elongate
Although RSM P2523.8 has an estimated weight more than 40% greater than the next
largest known theropod taxon, specimens of several other theropod species (includingGiganotosaurus carolinii and Tyrannotitan chubutensis) have femoral proportions indicative of
body masses greater than those of most other adult T. rex specimens. As
such, it is likely that further sampling of these other giant theropods, all of which are represented
by fewer specimens than T. rex, may yield larger individuals that match or surpass the size of
RSM P2523.8. In the case of Giganotosaurus carolinii, a sing dentary is known that does hint at
a greater maximum size (Calvo, 2000).