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Temporal range: Early Eocene (Casamayoran-Mustersan)
~48.6–48.0  Ma
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Ameghino, 1901

Thomashuxleya is an extinct genus of notoungulate mammal, named after famous 19th-century biologist Thomas Huxley.

Biologist scientist studying living organisms

A biologist is a scientist who has specialized knowledge in the field of biology, the scientific study of life. Biologists involved in fundamental research attempt to explore and further explain the underlying mechanisms that govern the functioning of living matter. Biologists involved in applied research attempt to develop or improve more specific processes and understanding, in fields such as medicine and industry.


Thomashuxleya was about 1.3 metres (4.3 ft) in length and weighted an estimated 113 kilograms (249 lb), with a heavy body and strong limbs. [1] Its large skull had 44 teeth in its jaws, including large tusks which may have been used to dig around in earth. It had four toes on each foot, and probably walked somewhat like a modern peccary. It was a relatively generalised animal, not specialised for any particular way of life. [2] There's an almost complete skeleton of this animal in exhibition in the American Museum of Natural History. This skeleton was discovered during the Scarrit expedition to Patagonia, Argentina, that was led by the paleontologist George Gaylord Simpson. Fossils of Thomashuxleya have been found in the Sarmiento and Casamayor Formations of Argentina. [3]

Skull bony structure that forms the skeleton of head in most vertebrates, supports the structures of the face and provides a protective cavity for the brain, composed of two parts: the cranium and the mandible

The skull is a bony structure that forms the head in vertebrates. It supports the structures of the face and provides a protective cavity for the brain. The skull is composed of two parts: the cranium and the mandible. In the human, these two parts are the neurocranium and the viscerocranium or facial skeleton that includes the mandible as its largest bone. The skull forms the anterior most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton.

Jaw opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food;structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of most animals

The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of most animals.

Peccary family of mammals

A peccary is a medium-sized pig-like hoofed mammal of the family Tayassuidae. They are found throughout Central and South America and in the southwestern area of North America. Peccaries usually measure between 90 and 130 cm in length, and a full-grown adult usually weighs about 20 to 40 kg.

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  1. D. Patterson, Bruce (€2012) Bones, Clones, and Biomes: The History and Geography of Recent Neotropical Mammals p.83
  2. Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 251. ISBN   1-84028-152-9.
  3. Thomashuxleya at