OBJECT DOSSIER · SMITHSONIAN OPEN ACCESS

Early synapsid — Dimetrodon grandis

SAGE Museum Deep Time scientific dossier

Artist / Creator

Dallas Krentzel

Date / Period

Early Permian · Early Permian; Smithsonian specimens of Dimetrodon grandis come from Early Permian rocks of Texas.

Object Type

composite

Medium

unknown_needs_review

About This Object

Geologic period: Early Permian

Age: Early Permian; Smithsonian specimens of Dimetrodon grandis come from Early Permian rocks of Texas.

Feeding: Predatory. Large serrated teeth and prominent canine-like teeth supported processing of vertebrate prey.

Locomotion: Terrestrial quadruped.

Body plan: Large quadrupedal synapsid with a deep skull, differentiated teeth and greatly elongated neural spines.

Evidence: Skull, teeth, vertebrae, limbs and elongated neural spines are directly preserved.

Why it matters: Dimetrodon is one of the clearest animals for breaking the popular misconception that every large prehistoric reptile-looking animal was a dinosaur.

Plain Language Identity: A large Early Permian predatory synapsid famous for the tall neural spines forming a sail-like structure along its back.

What You Are Looking At: A composite skeletal display representing Dimetrodon grandis.

Defense Or Attack: Powerful jaws and differentiated teeth were its primary feeding and attack equipment.

Ecosystem: Early Permian terrestrial ecosystems of North America.

Preservation: Composite museum mount based on fossil skeletal material.

Find Location: Texas, United States.

Open Questions: The biological function of the famous sail is not completely settled. Proposed functions should be labeled as hypotheses rather than fact.

Source Urls: https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list; https://www.si.edu/object/nmnhpaleobiology_3451030; https://www.si.edu/object/dimetrodon-grandis-romer-price-1940:nmnhpaleobiology_3451032; https://www.smithsonianmag.com/blogs/smithsonian-books/2023/11/16/five-incredible-fossils-from-across-the-world/

Enrichment Method: SAGE curated research pass; title and scientific name matched; current research distinctions retained; evidence separated from inference

Scientific name: Dimetrodon grandis

Evidence / representation: comparative_taxon_visual

Why It Is In This SAGE Exhibit

comparative_taxon_visual

The Permian World: Strange Bodies and the Great Dying.

Provenance

Smithsonian Deep Time source scene: Life Changes in the Permian

Visual source institution: Wikimedia Commons

Exhibition History

Included in the SAGE Museum Dinosaurs & Deep Time staging exhibit.

Collection & Credit

Media license: CC BY 2.0

https://creativecommons.org/licenses/by/2.0

Subjects & Themes

Dimetrodon grandis Early Permian composite Life Changes in the Permian The Permian World

ORIGINAL COLLECTION SOURCE

This object page stays inside SAGE Museum. The Smithsonian link below is provided only as the original scholarly collection record. It opens separately.

VIEW ORIGINAL SMITHSONIAN RECORD ↗