Thomas R. Holtz Jr.

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Tom Holtz, Jr.
Born (1965-09-13) September 13, 1965 (age 58)
University of Maryland, Department of Geology
Author abbrev. (zoology)HOLTZ, T.R., JR
Websitewww.geol.umd.edu/~tholtz/

Thomas Richard Holtz Jr. (born September 13, 1965) is an American vertebrate

Dinosaurs and is the author or co-author of the chapters "Saurischia",[2] "Basal Tetanurae",[3] and "Tyrannosauroidea"[4] in the second edition of The Dinosauria. He has also been consulted as a scientific advisor for the Walking with Dinosaurs BBC series as well as the Discovery special When Dinosaurs Roamed America, and has appeared in numerous documentaries focused on prehistoric life, such as Jurassic Fight Club on History and Monsters Resurrected, Dinosaur Revolution and Clash of the Dinosaurs on Discovery.[5]

Holtz is also the director of the Science and Global Change Program within the

College Park Scholars
living-learning community at the University of Maryland, College Park.

Early life

Holtz was born in California. He has stated that he wanted to be a dinosaur as a child, but upon learning that it is impossible to turn into a dinosaur he shifted his goals to study them. He attended Johns Hopkins University, where he met his future wife. He then attended Yale, where he met John Ostrom, who served as his academic advisor.[6]

Theories

Holtz has come up with several new theories and hypotheses about the dinosaurs' classification. For example, he coined the terms

paraphyletic, or "artificial", clades. For example, troodontids are now known to be deinonychosaurs, or "raptors", closely related to dromaeosaurids and birds. The discovery of basal tyrannosauroids, such as Guanlong, which lacked an arctometatarsus, also helped to disprove this theory. And, eventually, the "skull capsule" in troodontids and ornithomimosaurs was found to be an example of convergent evolution
, causing the clade Bullatosauria to be abandoned.

Gallimimus, an example ornithomimosaurian theropod that Holtz assigned to the Bullatosauria

Holtz was also a key figure in the discovery that tyrannosauroids were not

monophyletic
Carnosauria that contained Megalosauroidea, Allosauroidea and Tyrannosauroidea. However, fellow vertebrate paleontologist Oliver Rauhut is known to recover a monophyletic Carnosauria that contains both Megalosauroidea and Allosauroidea in many of his publications, although like most researcher he agrees that Tyrannosauroids are likely Coelurosaurians as based on the conclusions made by Holtz.

Selected publications

Footnotes

  1. ^ Holtz, Thomas R. Holtz Jr..
  2. ^ "Saurischia", pp. 21–23, with H. Osmólska
  3. ^ "Basal Tetanurae", pp. 71–110, with R. E. Molnar, P. J. Currie
  4. ^ "Tyrannosauroidea", pp. 111–136.
  5. ^ Holtz, Thomas R. Jr. (September 8, 2011). Comment on "Coming soon to your screens: Dinosaur Hyperbole", weblog entry by Hone, Dave (September 7, 2011). Dave Hone's Archosaur Musings. Retrieved September 13, 2011.
  6. ^ "Interview with Dr. Thomas R. Holtz, Jr". Buzzy Magazine.

References