Re: [dinosaur] Tyrannosaurus rex as an invasive species

[Thomas Richard Holtz <tholtz@umd.edu>]

The rationale behind this is that TyrannosaurusÂis more closely related to TarbosaurusÂand Zhuchengtyrannus than it was to other North American tyrannosaurines. Furthermore, these Asian tyrannosaurininsÂare older than Tyrannosaurus. So the hypothesis is that this lineage of tyrannosaur originated in Asia, and the ancestor ofÂTyrannosaurusÂmigrated into North America before the late Maastrichtian.

The spread isn't a problem: once a taxon makes it from one continent to another it can spread to the limits of its mobility and habitat in relatively quick periods. We see the same when Cenozoic mammals crossed Beringia either direction, or when they crossed the Isthmus of Panama.

On Fri, Feb 26, 2021 at 6:39 AM Poekilopleuron <dinosaurtom2015@seznam.cz> wrote:

Good day!

I would like to ask, if there is any support in the fossil record for the idea that a giant theropod Tyrannosaurus rex was actually an invasive species (migrating perhaps from Eastern Asia) that "flooded" North American ecosystems at the very end of the Cretaceous? Given that the fossils of this species are found thousands of kilometres away from each other (British Columbia to Mexico), that would make sense, perhaps? Thank you for your thoughts! Tom

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Thomas R. Holtz, Jr.
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