Peck's Rex
Encyclopedia
Peck's Rex is the nickname (specimen number MOR
980) given to a fossil
specimen of the dinosaur
species Tyrannosaurus rex, found in Montana
in 1997. The excavation was led by J. Keith Rigby, and the fossil got its nickname after Fort Peck, which is located close to the place of discovery. Peck's Rex has been part of several exhibitions on dinosaurs, and is specifically famous because it was the first specimen of its species to have Metacarpal III preserved.
, and hipbone with complete ischium and pubis. The left hindleg is relatively complete, missing only some toe bones. The forelimbs include the scapula
and furcula
, both humeri
and right hand phalanges, as well as metacarpal III. Because the skeleton is of the gracile morphotype, Peck's Rex is believed to be a male
, although the hypothesis
which suggests that the sex of Tyrannosaurus specimens can be determined by the degree of skeletal sturdiness has been debated in recent years. Peck's Rex has been the subject of research regarding parasitic infections in dinosaurs. The forelimbs of Peck's Rex have also been studied as they show evidence of use. This evidence includes the construction of metacarpal III, as well as repeated fractures in the furcula
- possibly caused by heavy loads or pressure (Carpenter and Lipkin, 2005).
, the Fort Peck Interpretive Center and Museum (beside a lifesized model), and the Carnegie Museum of Natural History
as part of the exhibit: Dinosaurs in Their Time where it is mounted in a "face off" position against the holotype
Tyrannosaurus skeleton (CM 9380).. Cast pieces and skeletons of Peck's rex (like forelimbs, teeth, and parts of the jaws and feet) are also for sale.
Museum of the Rockies
The Museum of the Rockies, is located in Bozeman, Montana. The museum, originally affiliated with Montana State University in Bozeman, and now, also the Smithsonian Institution, is known for its paleontological collections, although these are not its sole focus...
980) given to a fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
specimen of the dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
species Tyrannosaurus rex, found in Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
in 1997. The excavation was led by J. Keith Rigby, and the fossil got its nickname after Fort Peck, which is located close to the place of discovery. Peck's Rex has been part of several exhibitions on dinosaurs, and is specifically famous because it was the first specimen of its species to have Metacarpal III preserved.
Description
The fossil of Peck's Rex is relatively well preserved. The skeleton includes a relatively complete skull with jaws, multiple vertebrae of the back and tail, a well preserved gastraliumGastralium
Gastralia are dermal bones found in the ventral body wall of crocodilian and Sphenodon species. They are found between the sternum and pelvis, and do not articulate with the vertebrae...
, and hipbone with complete ischium and pubis. The left hindleg is relatively complete, missing only some toe bones. The forelimbs include the scapula
Scapula
In anatomy, the scapula , omo, or shoulder blade, is the bone that connects the humerus with the clavicle ....
and furcula
Furcula
The ' is a forked bone found in birds, formed by the fusion of the two clavicles. In birds, its function is the strengthening of the thoracic skeleton to withstand the rigors of flight....
, both humeri
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
and right hand phalanges, as well as metacarpal III. Because the skeleton is of the gracile morphotype, Peck's Rex is believed to be a male
Male
Male refers to the biological sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization...
, although the hypothesis
Hypothesis
A hypothesis is a proposed explanation for a phenomenon. The term derives from the Greek, ὑποτιθέναι – hypotithenai meaning "to put under" or "to suppose". For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it...
which suggests that the sex of Tyrannosaurus specimens can be determined by the degree of skeletal sturdiness has been debated in recent years. Peck's Rex has been the subject of research regarding parasitic infections in dinosaurs. The forelimbs of Peck's Rex have also been studied as they show evidence of use. This evidence includes the construction of metacarpal III, as well as repeated fractures in the furcula
Furcula
The ' is a forked bone found in birds, formed by the fusion of the two clavicles. In birds, its function is the strengthening of the thoracic skeleton to withstand the rigors of flight....
- possibly caused by heavy loads or pressure (Carpenter and Lipkin, 2005).
Exhibition and sales
Casts of Peck's Rex have been featured at several museums including the Maryland Science CenterMaryland Science Center
The Maryland Science Center, located in Baltimore's Inner Harbor, opened to the public in 1976. It includes three levels of exhibits, a planetarium, and an observatory. It was one of the original structures that drove the revitalization of the Baltimore Inner Harbor from its industrial roots to a...
, the Fort Peck Interpretive Center and Museum (beside a lifesized model), and the Carnegie Museum of Natural History
Carnegie Museum of Natural History
Carnegie Museum of Natural History, located at 4400 Forbes Avenue in the Oakland neighborhood of Pittsburgh, Pennsylvania, USA, was founded by the Pittsburgh-based industrialist Andrew Carnegie in 1896...
as part of the exhibit: Dinosaurs in Their Time where it is mounted in a "face off" position against the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
Tyrannosaurus skeleton (CM 9380).. Cast pieces and skeletons of Peck's rex (like forelimbs, teeth, and parts of the jaws and feet) are also for sale.
