Shawn P Zack

Interests

Teaching

Anatomy, biology

Research

Paleontology, comparative anatomy, stratigraphy

Courses

No activities entered.

Scholarly Contributions

Chapters

• Zack, S. P. (2008).

  Postcranial Morphology of Apheliscus and Haplomylus (Condylarthra, Apheliscidae): Evidence for a Paleocene Holarctic Origin of Macroscelidea

  . In Mammalian Evolutionary Morphology: A Tribute to Frederick S. Szalay. Springer, Dordrecht. doi:10.1007/978-1-4020-6997-0_5
  More info

  Small-bodied eutherian mammals with bunodont teeth from the Paleocene and Eocene have long been the subjects of taxonomic contention, with regard to both the assignment of individual genera to supergeneric clades (such as Hyopsodontidae, Pentacodontidae, and Dormaalidae) and to the place of those larger groups within Eutheria. Taxa traditionally placed in the family Hyopsodontidae have proven particularly problematic from the first standpoint, the clade has become a wastebasket for small-bodied, bunodont taxa whose morphology suggests affinities with the basal ungulate order Condylarthra (in this study, Ungulata and ungulate refer to the traditional morphological concept of this group, minimally including Artiodactyla, Perissodactyla, Hyracoidea, 5. Postcranial Morphology of Apheliscus and Haplomylus (Condylarthra, Apheliscidae): Evidence for a Paleocene Holarctic Origin of Macroscelidea

Journals/Publications

• Tomiya, S., Zack, S., Spaulding, M., & Flynn, J. (2022). Erratum: Carnivorous mammals from the middle Eocene Washakie Formation, Wyoming, USA, and their diversity trajectory in a post-warming world (Journal of Paleontology (2021) 95:S82 (1-115) DOI: 10.1017/jpa.2020.74). Journal of Paleontology, 96(3). doi:10.1017/jpa.2021.126
  More info

  In the published version of this memoir (Tomiya et al., 2021), the species name of Patriofelis ulta Leidy, 1870, was inadvertently misspelled.
• Zack, S. P., Poust, A., & Wagner, H. (2022). Diegoaelurus, a new machaeroidine (Oxyaenidae) from the Santiago Formation (late Uintan) of southern California and the relationships of Machaeroidinae, the oldest group of sabertooth mammals. PeerJ, 10, e13032.
  More info

  Manuscript describing a new genus and species of saber-tooth mammal
• Dunn, R., Penkrot, T. A., & Zack, S. P. (2020). Morphology of the Semicircular Canals and Locomotion of Zionodon satanus. The FASEB Journal, 34(S1).
• Tomiya, S., Zack, S. P., Spaulding, M., & Flynn, J. J. (2021). Carnivorous mammals from the middle Eocene Washakie Formation, Wyoming, USA, and their diversity trajectory in a post-warming world. Journal of Paleontology, 95, Memoir 82, 1-115.
  More info

  Collaborative work describing new fossil material. My contribution is primarily the "Oxyaenodonta" and "Hyaenodonta" in the article title.DO NOT count this for 2021. I counted it last year because the final version (including proofs) was submitted in 2020.
• Zack, S. P., Rose, K. D., Holbrook, L. T., Kumar, K., Rana, R. S., & Smith, T. (2016). An enigmatic new family of ungulate-like mammals from the early Eocene of India. Papers in Palaeontology.
  More info

  DO NOT COUNT FOR 2021!! The version of record was online in 2019 (and was cited in papers published in 2019 and 2020), but it did not get a volume/issue/page numbers until 2021Description of a new taxon
• Zack, S. P. (2019).

  The first North American Propterodon (Hyaenodonta: Hyaenodontidae), a new species from the late Uintan of Utah (project)

  . PeerJ, 7, e8136. doi:10.7934/p3489
• Zack, S. P. (2019). A skeleton of a Uintan machaeroidine ‘creodont’ and the phylogeny of carnivorous eutherian mammals. Journal of Systematic Palaeontology, 17(8), 653-689.
• Zack, S. P. (2019). The first North American Propterodon (Hyaenodonta: Hyaenodontidae), a new species from the late Uintan of Utah. PeerJ, 7, e8136 (32 pages). doi:http://doi.org/10.7717/peerj.8136
• Zack, S. P., & Penkrot, T. A. (2016). Tarsals of the miniscule insectivorous mammal Batodonoides from the Eocene of San Diego County, California. Journal of Vertebrate Paleontology, 39(4), e1672076 (14 pages). doi:10.1080/02724634.2019.1672076
  More info

  Description of additional material from the same faunas as the material described by Penkrot and Zack (2016).
• Zack, S. P. (2018).

  A skeleton of a Uintan machaeroidine ‘creodont’ and the phylogeny of carnivorous eutherian mammals

  . Journal of Systematic Palaeontology, 17(8), 653-689. doi:10.1080/14772019.2018.1466374
• Liu, M., Zack, S. P., Lucas, L., Allen, D., & Fisher, R. E. (2016). Hind limb myology of the ringtail (Bassariscus astutus) and the myology of hind foot reversal. Journal of Mammalogy, 97(1), 211-233. doi:http://dx.doi.org/10.1093/jmammal/gyv171
  More info

  I am joint senior author of this manuscript with Margaret Liu.
• Penkrot, T. A., & Zack, S. P. (2016). Tarsals of Sespedectinae (?Lipotyphla) from the middle Eocene of southern California, and the affinities of Eocene “erinaceomorphs”. Journal of Vertebrate Paleontology, 36(6), e1212059 (17 pages).
  More info

  Published in 2016.
• Zack, S. P. (2016).

  Tarsals of Sespedectinae (?Lipotyphla) from the middle Eocene of southern California, and the affinities of Eocene ‘erinaceomorphs’

  . Journal of Vertebrate Paleontology, 36(6), e1212059. doi:10.1080/02724634.2016.1212059
• Rana, R. S., Kumar, K., Zack, S. P., Sole, F., Rose, K. D., Singh, L., Sahni, A., & Smith, T. (2015). Craniodental and Postcranial Morphology of Indohyaenodon raoi from the Early Eocene of India, and Its Implications for Ecology, Phylogeny, and Biogeography of Hyaenodontid Mammals. Journal of Vertebrate Paleontology, 35(5), e965308 (22 pages). doi:10.1080/02724634.2015.965308
  More info

  My role is corresponding author, and I have written the descriptive and phylogenetic sections of this manuscript.
• Zack, S. P., & Rose, K. D. (2015). The postcranial skeleton of Galecyon: evidence for morphological and locomotor diversity in early Hyaenodontidae (Mammalia: Creodonta). Journal of Vertebrate Paleontology, 35(6), e1001492 (25 pages). doi:10.1080/02724634.2014.1001492
• Zack, S. P. (2012).

  Deciduous dentition of Didymictis (Carnivoramorpha: Viverravidae): implications for the first appearance of “Creodonta”

  . Journal of Mammalogy, 93(3), 808-817. doi:10.1644/11-mamm-a-245.1
  More info

  Deciduous teeth of Carnivoramorpha can differ substantially from their permanent structural and functional counterparts, particularly dP4. As a consequence, isolated carnivoramorphan deciduous teeth have repeatedly been misidentified as permanent teeth of different, often unrelated taxa. Due in part to this potential for misidentification, the deciduous dentitions of basal carnivoramorphans remain poorly documented. This study describes and illustrates the 1st known deciduous premolars of a member of the basal carnivoramorphan family Viverravidae, with dP3–4 and dp3–4 of the early Eocene Didymictis protenus (Cope, 1874) documented by specimens associated with permanent teeth. The morphology of these specimens permits a reconsideration of the affinities of 2 mid-Paleocene taxa, Deltatherium durini Van Valen, 1978 and Prolimnocyon macfaddeni Rigby, 1980, that have been proposed to represent the earliest known members of the family Hyaenodontidae and the order “Creodonta.” Both species are founded on viverravid deciduous premolars. Reidentification of these taxa eliminates the Paleocene record of hyaenodontids from North America.
• Zack, S. P. (2011).

  New Species of the Rare Early Eocene Creodont Galecyon and the Radiation of Early Hyaenodontidae

  . Journal of Paleontology, 85(2), 315-336. doi:10.1666/10-093.1
  More info

  Galecyon is one of the first appearing hyaenodontid creodonts, as well as one of the most poorly known. New specimens greatly improve our understanding of the morphology of this early Eocene genus, thereby enhance knowledge of the earliest radiation of Hyaenodontidae, and include the first associated upper dental remains, as well as fragmentary cranial remains. The new records substantially expand the stratigraphic range of the genus and allow recognition of two new species. The first, Galecyon peregrinus n. sp., is a small, early species that includes the first records of Galecyon from the earliest Eocene Wa-0 interval. The second, Galecyon chronius n. sp., is a large, terminal species, represented by numerous specimens that extend the range of the genus into the late Wasatchian. The type species, G. mordax, is restricted to specimens that are intermediate in size and stratigraphic position. Phylogenetic analysis of early hyaenodontids confirms the monophyly of Galecyon and places it basal to Prolimnocyon, Prototomus, and Pyrocyon. Arfia is identified as the earliest diverging hyaenodontid sampled, contrasting with prior support for a more crownward position. Prototomus martis is more closely allied to Pyrocyon than to other species of Prototomus. The three North American species of Galecyon form a probable anagenetic lineage.
• Zack, S. P. (2004).

  An Early Eocene arctostylopid (Mammalia: Arctostylopida) from the Green River Basin, Wyoming

  . Journal of Vertebrate Paleontology, 24(2), 498-501. doi:10.1671/3059

Presentations

• Tomiya, S., Zack, S. P., Spaulding, M., & Flynn, J. J. (2019, October). Carnivorous mammals from the middle Eocene Washakie Formation, Wyoming, U.S.A., and their diversity trajectory in a post-warming world. Society of Vertebrate Paleontology Annual Meeting. Brisbane, Queensland, Australia: Society of Vertebrate Paleontology.
• Penkrot, T. A., & Zack, S. P. (2014, October). Tarsals of Sespedectinae (Eulipotyphlya, Erinaceomorpha) from the middle Eocene of southern California. Society of Vertebrate Paleontology.
• Smith, T., Rana, R. S., Kumar, K., Zack, S. P., Sole, F., Rose, K. D., Missiaen, P., Singh, L., & Sahni, A. (2014, October). New specimens of Indohyaenodon raoi from the early Eocene of Vastan mine, India and their implications for phylogeny and biogeography of hyaenodontid mammals. Society of Vertebrate Paleontology.
• Zack, S. P. (2014, October). Saber-tooth origins: a new skeletal association and the affinities of Machaeroidinae (Mammalia, Creodonta). Society of Vertebrate Paleontology.
• Zack, S. P. (2013, October). A reassessment of the monophyly of Carnivoramorpha (Mammalia). Society of Vertebrate Paleontology Annual Meeting. Los Angeles, California: Society of Vertebrate Paleontology.

Poster Presentations

• Zack, S. P. (2023, November). A new species of Simidectes from the early Uintan of California clarifies the affinities of the genus. Society of Vertebrate Paleontology Annual Meeting. Virtual: Society of Vertebrate Paleontology.
• Zack, S. P., & Penkrot, T. A. (2021, November). New material of Lophiparamys (Mammalia: Rodentia), including tarsals, from the Willwood Formation (early Eocene). Society of Vertebrate Paleontology Annual Meeting. Virtual: Society of Vertebrate Paleontology.
• Zack, S. P., Rose, K. D., & O'Leary, M. (2022, November). New information on the enigmatic Wyolestes and the affinities of the genus. Society of Vertebrate Paleontology Annual Meeting. Virtual: Society of Vertebrate Paleontology.
• Penkrot, T. A., & Zack, S. P. (2019, October). New postcrania of Sciuravidae (Rodentia): implications for locomotion and phylogeny. Society of Vertebrate Paleontology Annual Meeting. Brisbane, Queensland, Australia: Society of Vertebrate Paleontology.
• Zack, S. P. (2019, October). The first North American Propterodon (Mammalia: Hyaenodonta) from the late Uintan of Utah. Society of Vertebrate Paleontology Annual Meeting. Brisbane, Queensland, Australia: Society of Vertebrate Paleontology.
• Smith, T., Rana, R., Kumar, K., Folie, A., Dunn, R., Solé, F., Zack, S. P., & Rose, K. D. (2018, October). New data on the early Eocene mammals and other vertebrates from the Cambay Shale Formation exposed in lignite mines of Gujarat, western India. Society of Vertebrate Paleontology Annual Meeting. Albuquerque, New Mexico: Society of Vertebrate Paleontology.
• Zack, S. P., & Penkrot, T. A. (2018, October). New leptictids (Mammalia) from the Uintan (Eocene) of San Diego County, California. Society of Vertebrate Paleontology Annual Meeting. Albuquerque, New Mexico: Society of Vertebrate Paleontology.
• Zack, S. P., Rose, K. D., Kumar, K., Rana, R. S., & Smith, T. (2017, August). An enigmatic new ungulate from the early Eocene of India. Society of Vertebrate Paleontology Annual Meeting. Calgary, Alberta: Society of Vertebrate Paleontology.
• Penkrot, T. A., & Zack, S. P. (2016, October). Tarsal diversity of middle Eocene (Uintan) rodents from San Diego County, California. Society of Vertebrate Paleontology Annual Meeting. Salt Lake City: Society of Vertebrate Paleontology.
• Tomiya, S., Spaulding, M., & Zack, S. P. (2016, October). Diversity and turnover of mammalian carnivores from the middle Eocene Washakie Formation, Wyoming, USA. Society of Vertebrate Paleontology Annual Meeting. Salt Lake City: Society of Vetrebrate Paleontology.
• Zack, S. P., & Tomiya, S. (2016, October). New postcrania clarify the affinities of the unusual Eocene mammal Simidectes. Society of Vertebrate Paleontology Annual Meeting. Salt Lake City: Society of Vertebrate Paleontology.
• Penkrot, T. A., & Zack, S. P. (2015, October). Small lipotyphlan tarsals from the Eocene of San Diego County, California. Society of Vertebrate Paleontology. Dallas, Texas: Society of Vertebrate Paleontology.
• Penkrot, T. A., Zack, S. P., & Strait, S. (2013, October). The diversity of small mammalian tarsals from Castle Gardens, earliest Eocene of Wyoming. Society of Vertebrate Paleontology Annual Meeting. Los Angeles, California: Society of Vertebrate Paleontology.