{{italictitle}}
{{italictitle}}
{{Taxobox
| name =
Juravenator
| fossil_range =
Late JurassicThe Late Jurassic epoch of the Jurassic Period is the unit of geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago, which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name Malm indicates rocks of Late Jurassic age...
| image = Juravenator BW.jpg
| image_width = 250px
| image_caption = Artist's impression
| regnum =
AnimalAnimals are a major group of mostly multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously...
ia
| phylum =
ChordataChordates are animals which are either vertebrates or one of several closely related invertebrates. They are united by having, for at least some period of their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail...
| classis =
ReptiliaReptiles, or members of the class Reptilia, are air-breathing, generally "cold-blooded" amniotes that generally have skin covered in scales or scutes. They are tetrapods and lay amniote eggs, whose embryos are surrounded by the amnion membrane...
| superordo =
Dinosaur{{Otheruses}}{{pp-semi-protected|small=yes}}{{Otheruses}}{{pp-semi-protected|small=yes}}{{Taxobox|name = Dinosaurs|fossil_range = {{Fossil range|230|65|earliest=230|latest=0|PS=
Descendant taxon Aves survives to present.}}|image = field_dinos_2.jpg...
ia
| ordo =
SaurischiaSaurischia is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...
| unranked_familia =
CoelurosauriaCoelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. It is a diverse group that includes tyrannosaurs, ornithomimosaurs, and maniraptors; Maniraptora includes birds, the only descendents of coelurosaurs alive today...
| familia =
CompsognathidaeCompsognathidae is a family of small carnivorous dinosaurs, generally conservative in form, from the Jurassic and Cretaceous Periods. Compsognathids lie at or near the origin of feathers--skin impressions are known from three genera, Sinosauropteryx, Sinocalliopteryx, and Juravenator...
?
| genus =
Juravenator
| genus_authority = Göhlich & Chiappe, 2006
| subdivision_ranks =
SpeciesIn biology, a species is:* a taxonomic rank or* a unit at that rank ....
| subdivision =
J.
{{italictitle}}
{{italictitle}}
{{Taxobox
| name =
Juravenator
| fossil_range =
Late JurassicThe Late Jurassic epoch of the Jurassic Period is the unit of geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago, which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name Malm indicates rocks of Late Jurassic age...
| image = Juravenator BW.jpg
| image_width = 250px
| image_caption = Artist's impression
| regnum =
AnimalAnimals are a major group of mostly multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously...
ia
| phylum =
ChordataChordates are animals which are either vertebrates or one of several closely related invertebrates. They are united by having, for at least some period of their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail...
| classis =
ReptiliaReptiles, or members of the class Reptilia, are air-breathing, generally "cold-blooded" amniotes that generally have skin covered in scales or scutes. They are tetrapods and lay amniote eggs, whose embryos are surrounded by the amnion membrane...
| superordo =
Dinosaur{{Otheruses}}{{pp-semi-protected|small=yes}}{{Otheruses}}{{pp-semi-protected|small=yes}}{{Taxobox|name = Dinosaurs|fossil_range = {{Fossil range|230|65|earliest=230|latest=0|PS=
Descendant taxon Aves survives to present.}}|image = field_dinos_2.jpg...
ia
| ordo =
SaurischiaSaurischia is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...
| unranked_familia =
CoelurosauriaCoelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. It is a diverse group that includes tyrannosaurs, ornithomimosaurs, and maniraptors; Maniraptora includes birds, the only descendents of coelurosaurs alive today...
| familia =
CompsognathidaeCompsognathidae is a family of small carnivorous dinosaurs, generally conservative in form, from the Jurassic and Cretaceous Periods. Compsognathids lie at or near the origin of feathers--skin impressions are known from three genera, Sinosauropteryx, Sinocalliopteryx, and Juravenator...
?
| genus =
Juravenator
| genus_authority = Göhlich & Chiappe, 2006
| subdivision_ranks =
SpeciesIn biology, a species is:* a taxonomic rank or* a unit at that rank ....
| subdivision =
J. starki Göhlich & Chiappe, 2006
}}
Juravenator is a
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
of small (70 cm long) coelurosaurian
dinosaur{{Otheruses}}{{pp-semi-protected|small=yes}}{{Otheruses}}{{pp-semi-protected|small=yes}}{{Taxobox|name = Dinosaurs|fossil_range = {{Fossil range|230|65|earliest=230|latest=0|PS=
Descendant taxon Aves survives to present.}}|image = field_dinos_2.jpg...
, which lived in the area which would someday become the
Jura mountainsThe Jura Mountains are a small mountain range located north of the Alps, separating the Rhine and Rhone rivers and forming part of the watershed of each. The mountain range sensu Johann Gottfried Ebel is located in France, Switzerland, and Germany...
of
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
, 150 million years ago.
The fossil, found in 1998 by amateur paleontologist Klaus-Dieter Weiß in a lime pit near
EichstättEichstätt is a city in the federal state of Bavaria, Germany, and capital of the District of Eichstätt. It is located along the Altmühl River, at , and had a population of 13,078 in 2002. It is home to the Katholische Universität Eichstätt-Ingolstadt, the lone Catholic university in Germany.St...
, had been nicknamed
Borsti in German, a name commonly given to bristle-haired dogs, on the assumption the creature was endowed with bristly protofeathers.
Feathers and scales
Juravenator was originally classified as a member of the family
CompsognathidaeCompsognathidae is a family of small carnivorous dinosaurs, generally conservative in form, from the Jurassic and Cretaceous Periods. Compsognathids lie at or near the origin of feathers--skin impressions are known from three genera, Sinosauropteryx, Sinocalliopteryx, and Juravenator...
, making it a close relative of
CompsognathusCompsognathus was a small, bipedal, carnivorous theropod dinosaur. The animal was the size of a turkey and lived around 150 million years ago, the early Tithonian stage of the late Jurassic Period, in what is now Europe...
, which preserved evidence of scales on the tail of one specimen, but also of
SinosauropteryxSinosauropteryx is the first and most primitive genus of dinosaur found with the fossilized impressions of feathers. It lived in China during the early Cretaceous period and may have been a close relative of Compsognathus. It was the first dinosaur genus discovered from the famous Jehol Biota of...
and
SinocalliopteryxSinocalliopteryx is a genus of compsognathid dinosaur from the Lower Cretaceous Yixian Formation of China...
, for which there is fossil evidence of a downy, feather-like covering. However, a patch of fossilized
Juravenator skin (from the tail base and hind leg) shows primarily normal dinosaur scales, as well as traces of what may be simple feathers. Paleontologist Xu Xing, in his comments on the find in the journal
Nature, suggested that the presence of scales on the tail of
Juravenator could mean that the feather coat of early feathered dinosaurs was more variable than seen in modern birds. Xu also questioned the interpretation of
Juravenator as a compsognathid, suggesting the extensive scaly hide could be a primitive trait, though
Compsognathus itself also preserves scales on its tail. Xu considered it most likely that
Juravenator and other primitive feathered dinosaurs simply possessed more extensive scales on their bodies than modern birds, which retain scales only on the feet and lower legs. This interpretation was supported by further study of the
Juravenator fossil, which revealed faint impressions of filamentous structures that may be primitive feathers.
Classification
While first classified as a member of the family
CompsognathidaeCompsognathidae is a family of small carnivorous dinosaurs, generally conservative in form, from the Jurassic and Cretaceous Periods. Compsognathids lie at or near the origin of feathers--skin impressions are known from three genera, Sinosauropteryx, Sinocalliopteryx, and Juravenator...
, subsequent studies have found problems with the initial study that produced those findings. Rather than grouping it with
Sinosauropteryx and other compsognathids, Butler
et al. found that it was not a compsognathid, but rather a basal member of the group
ManiraptoraManiraptora 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 Alvarezsauridae...
. Studies conflict on whether or not compsognathids belong to this later group or are more primitive, though all other maniraptoran skin impressions also show evidence of feathers.
External links
{{portalpar|Dinosaurs}}