Falcarius
Encyclopedia
Falcarius is a genus
of therizinosaur
ian dinosaur
found in east-central Utah
, United States
. Its name is derived from the word sickle
('falcarius' in Latin
being a sickle cutter), which scientists have used to describe its unwieldy clawed hands. This find, along with the recently discovered therizinosauroid Beipiaosaurus
from the Early Cretaceous
of China
, may clarify the group's relationship with the larger family of theropod dinosaurs.
ized bones from several individual animals, scientists have shown that Falcarius utahensis averaged 3.7 to 4 m (12 to 13 ft) in length and just over 1.2 m (4 ft) tall. With its long neck, it could apparently reach about 1.5 m (5 ft) off the ground to munch leaves or fruit. Its leaf-shaped teeth and 10 to 13 cm (4 to 5 inch) claws indicate that it consumed both meat, quite probably small animals such as lizards, and plant material.
Falcarius lived approximately 126 million years ago, in the Barremian
stage of the early Cretaceous
Period.
, part of the group Maniraptora
. Falcarius itself probably does not belong to this former group, although it does belong to the more inclusive group Therizinosauria. The group is characterized by bird
-like wide hips, a comparatively large brain
case and long necks with hollow bones typical of plant eaters. The less-primitive Asian specimens were covered in quill-like feather
s; this is assumed for Falcarius as well.
(Yellow Cat member), includes the remains of hundreds, perhaps thousands, of specimens of the new species. Only a small number of the available fossils have been excavated.
While a scientific description of Falcarius was published in 2004, it was not formally named until a subsequent paper was published in the May 2005 issue of the journal Nature
. Co-authors of the study include Scott Sampson, chief curator at the University of Utah
's Utah Museum of Natural History, and Lindsay Zanno, a doctoral student at the University. Dr. Sampson is quoted as saying that this species "...is the missing link between predatory dinosaurs and the bizarre plant-eating therizinosaurs".
A skeletal mount of Falcarius utahensis went on display at the Utah Museum of Natural History
on 29 June 2005.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of therizinosaur
Therizinosaur
Therizinosaurs are theropod dinosaurs belonging to the clade Therizinosauria. Therizinosaur fossils have been found in Early through Late Cretaceous deposits in Mongolia, the People's Republic of China and Western North America...
ian 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...
found in east-central Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Its name is derived from the word sickle
Sickle
A sickle is a hand-held agricultural tool with a variously curved blade typically used for harvesting grain crops or cutting succulent forage chiefly for feeding livestock . Sickles have also been used as weapons, either in their original form or in various derivations.The diversity of sickles that...
('falcarius' in Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
being a sickle cutter), which scientists have used to describe its unwieldy clawed hands. This find, along with the recently discovered therizinosauroid Beipiaosaurus
Beipiaosaurus
Beipiaosaurus is a genus of therizinosauroid theropod dinosaur from the Early Cretaceous of China.The exact classification of therizinosaurs had in the past been hotly debated, since their prosauropod-like teeth and body structure indicate that they were generally herbivorous, unlike typical...
from the Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
of China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, may clarify the group's relationship with the larger family of theropod dinosaurs.
Description
From examining fossilFossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
ized bones from several individual animals, scientists have shown that Falcarius utahensis averaged 3.7 to 4 m (12 to 13 ft) in length and just over 1.2 m (4 ft) tall. With its long neck, it could apparently reach about 1.5 m (5 ft) off the ground to munch leaves or fruit. Its leaf-shaped teeth and 10 to 13 cm (4 to 5 inch) claws indicate that it consumed both meat, quite probably small animals such as lizards, and plant material.
Falcarius lived approximately 126 million years ago, in the Barremian
Barremian
The Barremian is an age in the geologic timescale between 130.0 ± 1.5 Ma and 125.0 ± 1.0 Ma). It is a subdivision of the Early Cretaceous epoch...
stage of the early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
Period.
Classification
Falcarius closely resembles dinosaurs belonging to the family TherizinosauridaeTherizinosauridae
Therizinosauridae is a family of advanced herbivorous or omnivorous theropod dinosaurs. Therizinosaurid fossil remains have been recovered from mid-late Cretaceous Period deposits from Mongolia, China, and the United States.-Classification:...
, part of the group Maniraptora
Maniraptora
Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosauria and Therizinosauria. Ornitholestes and the Alvarezsauroidea...
. Falcarius itself probably does not belong to this former group, although it does belong to the more inclusive group Therizinosauria. The group is characterized by bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
-like wide hips, a comparatively large brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
case and long necks with hollow bones typical of plant eaters. The less-primitive Asian specimens were covered in quill-like feather
Feather
Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds and some non-avian theropod dinosaurs. They are considered the most complex integumentary structures found in vertebrates, and indeed a premier example of a complex evolutionary novelty. They...
s; this is assumed for Falcarius as well.
History of discovery
The discovery site, in a 2 acre (8,000 square meter) area of Utah's Cedar Mountain FormationCedar Mountain Formation
The Cedar Mountain Formation is the name given to distinctive sedimentary rocks in eastern Utah that occur between the underlying Morrison Formation and overlying Naturita Formation . It is composed of non-marine sediments, that is, sediments deposited in rivers, lakes and on flood plains...
(Yellow Cat member), includes the remains of hundreds, perhaps thousands, of specimens of the new species. Only a small number of the available fossils have been excavated.
While a scientific description of Falcarius was published in 2004, it was not formally named until a subsequent paper was published in the May 2005 issue of the journal Nature
Nature (journal)
Nature, first published on 4 November 1869, is ranked the world's most cited interdisciplinary scientific journal by the Science Edition of the 2010 Journal Citation Reports...
. Co-authors of the study include Scott Sampson, chief curator at the University of Utah
University of Utah
The University of Utah, also known as the U or the U of U, is a public, coeducational research university in Salt Lake City, Utah, United States. The university was established in 1850 as the University of Deseret by the General Assembly of the provisional State of Deseret, making it Utah's oldest...
's Utah Museum of Natural History, and Lindsay Zanno, a doctoral student at the University. Dr. Sampson is quoted as saying that this species "...is the missing link between predatory dinosaurs and the bizarre plant-eating therizinosaurs".
A skeletal mount of Falcarius utahensis went on display at the Utah Museum of Natural History
Utah Museum of Natural History
The Natural History Museum of Utah is a museum located at the Rio Tinto Center on the campus of the University of Utah in Salt Lake City, Utah, United States. The museum shows exhibits of natural history subjects, specifically about Utah's natural history...
on 29 June 2005.