Re: [dinosaur] Was T. rex subadult a dominant predator in its environment?

Consider pantherine cats. Lions are pack hunters; nearly all the other are solitary. All have similar prey, and some live side-by-side with lions and thus are in the same environment. Just because an adaptation might be advantageous doesn't mean it will be selected for in a given taxon. Behaviors like this must be evaluated on a case-by-case basis.

Consider that there is nearly equally-good evidence for "Nano" sized tyrannosauridsÂbeing pack hunters (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0103613) as there is for Dakotaraptor-sized dromaeosaurids (https://link.springer.com/article/10.1007/s00114-007-0310-7).Â

On Wed, Jul 17, 2019 at 2:46 AM Poekilopleuron <dinosaurtom2015@seznam.cz> wrote:

Good day, thank you for your response. I know there is no direct evidence of gregarious behaviour in dromaeosaurid theropod dinosaurs, but isnÂt it highly plausible because of its obvious advantages? In a pack, dromaeosaurids would be much more efficient hunters and it could even be an adaptation for living along large tyrannosarids (as a mean of chasing subadults from their prey, etc). Thank you, Tom

---------- PÅvodnÃ e-mail ----------
Od: Thomas Richard Holtz <tholtz@umd.edu>
Komu: Poekilopleuron <dinosaurtom2015@seznam.cz>
Datum: 16. 7. 2019 13:21:38
PÅedmÄt: Re: Was T. rex subadult a dominant predator in its environment?
You are presupposing that Dakotaraptor lived in packs. There is no evidence at present to determine that.

Certainly there would have been overlap between Nano-sized T. rex and Dakotaraptor in prey size. And as today, it is likely that rival predators engaged in kleptoparasitism all the time (just as hyenas & lions chase each other from kills).

On Tue, Jul 16, 2019 at 2:28 AM Poekilopleuron <dinosaurtom2015@seznam.cz> wrote:
Good day to all listmembers,

I was wondering if T. rex subadult (say 10 - 15 years old) was a dominant predator in its environment, just as an adult individuals. Could e. g. a pack of Dakotaraptors chase it away from its prey? Thank you for any thoughts! Tom

--
Thomas R. Holtz, Jr.
Email:Âtholtz@umd.eduÂÂÂÂÂÂÂÂ Phone: 301-405-4084
Principal Lecturer, Vertebrate Paleontology
Office: Geology 4106, 8000 Regents Dr., College Park MD 20742
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Phone: 301-405-6965
Fax: 301-314-9661ÂÂÂÂÂÂ ÂÂÂÂÂÂÂ

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Office: Centreville 1216, 4243 Valley Dr., College Park MD 20742
http://www.geol.umd.edu/sgc
Fax: 301-314-9843

Mailing Address:ÂÂÂÂÂÂÂ Thomas R. Holtz, Jr.
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Department of Geology
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Building 237, Room 1117
ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 8000 Regents Drive
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ University of Maryland
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ College Park, MD 20742-4211 USA

Thomas R. Holtz, Jr.
Email:Âtholtz@umd.eduÂÂÂÂÂÂÂÂ Phone: 301-405-4084
Principal Lecturer, Vertebrate Paleontology

Office: Geology 4106, 8000 Regents Dr., College Park MD 20742

Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/

Phone: 301-405-6965
Fax: 301-314-9661ÂÂÂÂÂÂ ÂÂÂÂÂÂÂ

Faculty Director, Science & Global Change Program, College Park Scholars

Office: Centreville 1216, 4243 Valley Dr., College Park MD 20742
http://www.geol.umd.edu/sgc
Fax: 301-314-9843

Mailing Address:ÂÂÂÂÂÂÂ Thomas R. Holtz, Jr.
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Department of Geology
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Building 237, Room 1117

ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 8000 Regents Drive
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ University of Maryland
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ College Park, MD 20742-4211 USA