Re: [dinosaur] Was T. rex a lion or rather a crocodile?

[Dann Pigdon <dannj@alphalink.com.au>]

On Sun, Aug 11th, 2019 at 10:54 PM, Thomas Richard Holtz <tholtz@umd.edu> wrote:

> Please remember: Tyrannosaurus rex (and indeed most dinosaurs) did not
> exist only as fully formed adults emerged from the mind of Zeus. They spent
> most of their life cycle as juveniles and sub-adults.

Given the high mortality rate associated with R-strategists, it's likely the 
"average" tyrannosaur wasn't 
very large at all (possibly not much larger than a hatchling). Very large 
tyrannosaurs are likely to be over-
represented in the fossil record due to preservational bias. 

Tyrannosaurs seem to have reached sexual maturity well before reaching their 
maximum size, so having 
few very large individuals in a population likely wouldn't have had much of an 
impact on their reproductive 
success. Too many very large geriatric animals may well have been a burden on 
the population rather 
than an advantage.

As to whether T.rex was leonine or crocodilian in nature; that depends on what 
you mean by 'crocodilian'. 
In the past there have been plenty of swift and agile terrestrial crocodilians 
that make our extant varieties 
look positively sluggish.

--
Dann Pigdon