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This diagram illustrates how scientists believe the dinosaur group theropoda shall be classed in a  phylogenetic tree, besides Sauropoda and Pterosauria. The main reason of this diagram is to show groups or families which had respiratory system like birds. AS in the diagram is abbreviations for "Airsacs", and ASW means "AirSacs supported by immobile femur and a knee-driven Walk". BL means "Bellow lungs". 
Airsacs are known in many different theropods, as well as in birds, which most scientists believe are descendants of dinosaurus. Air sacs are found in the primitive Tawa hallae,[1] the abelisaurid Majungasaurus,[2] as well as Allosauroids like Aerosteon.[3] There is also evidence for respiratory systems like penguinss in Deinonychosaurians.[4] The primitive bird Archaeopteryx also had airsacs (Bonde and Christiansen, 2000).
It is very likely that Deinonychosaurians had airsacs. We don't know  whether Deinonychosauria had a walking/breathing system with immobile thighbones, ASW (like birds) or movable thighbones. However, some people suggsest coeluosaurs had the same type of leg movement as birds ("kneedriven walking").[5]
Bellow lungs are lungs like our own, which alternately is filled with air, and thereafter emptied, after which you take a new breath. This type of lungs exist in mammals, most reptiles, and most amphibians (although some frogs get their oxygen through the skin). There is no evidence for airsacs in Ornithischia, so the likely had bellow lungs.
References.=

↑ (see the video at http://www.nsf.gov/news/special_reports/tawa/)

↑ (Claessens & O'connor, 2006).

↑ Alcober O.A, Sereno P.C, Larsson H.C.E et.al (2008), "Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina", Public Library of Science Journals.

↑ http://www.stumbleupon.com/su/20q5Z4/news.bbc.co.uk/2/hi/science/nature/7081166.stm

↑ http://www.geol.umd.edu/~tholtz/G104/lectures/104coelur.html.

This diagram illustrates how scientists believe the dinosaur group theropoda shall be classed in a phylogenetic tree, besides Sauropoda and Pterosauria. The main reason of this diagram is to show groups or families which had respiratory system like birds. AS in the diagram is abbreviations for "Airsacs", and ASW means "AirSacs supported by immobile femur and a knee-driven Walk". BL means "Bellow lungs". Airsacs are known in many different theropods, as well as in birds, which most scientists believe are descendants of dinosaurus. Air sacs are found in the primitive Tawa hallae,[1] the abelisaurid Majungasaurus,[2] as well as Allosauroids like Aerosteon.[3] There is also evidence for respiratory systems like penguinss in Deinonychosaurians.[4] The primitive bird Archaeopteryx also had airsacs (Bonde and Christiansen, 2000). It is very likely that Deinonychosaurians had airsacs. We don't know whether Deinonychosauria had a walking/breathing system with immobile thighbones, ASW (like birds) or movable thighbones. However, some people suggsest coeluosaurs had the same type of leg movement as birds ("kneedriven walking").[5] Bellow lungs are lungs like our own, which alternately is filled with air, and thereafter emptied, after which you take a new breath. This type of lungs exist in mammals, most reptiles, and most amphibians (although some frogs get their oxygen through the skin). There is no evidence for airsacs in Ornithischia, so the likely had bellow lungs. References.= ↑ (see the video at http://www.nsf.gov/news/special_reports/tawa/) ↑ (Claessens & O'connor, 2006). ↑ Alcober O.A, Sereno P.C, Larsson H.C.E et.al (2008), "Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina", Public Library of Science Journals. ↑ http://www.stumbleupon.com/su/20q5Z4/news.bbc.co.uk/2/hi/science/nature/7081166.stm ↑ http://www.geol.umd.edu/~tholtz/G104/lectures/104coelur.html.

Abelisauridae Aerosteon Archaeopteryx Deinonychosauria +7
Representative taxa from the latest Campanian–Maastrichtian faunas from Transylvania, western Romania. A–B Nidophis insularis (Serpentes, Madtsoiidae), articulated vertebrae (LPB (FGGUB) v.547/2) in left lateral (A) and dorsal (B) views (Densuş-Ciula Formation, Tuştea, Haţeg Basin; photo by Ştefan Vasile) C Allodaposuchus precedens (Eusuchia, ?Hylaeochampsidae), skull (PSMUBB V 438) in dorsal view (Sebeş = Şard Formation, Oarda de Jos, southwestern Transylvanian Basin; photo by Vlad Codrea/Massimo Delfino) D Theriosuchus sympiestodon (Mesoeucrocodylia, Atoposauridae), right maxilla (MCDRD 793) in lateral view (Sînpetru Formation, Sînpetru, Haţeg Basin) E–F Indeterminate titanosaur (?Magyarosaurus dacus) (Sauropoda, Titanosauria), isolated osteoderm (LPB (FGGUB) R.1410) in dorsal (E) and lateral (F) views (Sînpetru Formation, Sînpetru, Haţeg Basin) G Indeterminate ornithuran bird (Aves, Ornithurae), incomplete left tibiotarsus (LPB (FGGUB) R.1902) in anterior view (Densuş-Ciula Formation, Vălioara, Haţeg Basin) H Balaur bondoc (Theropoda, Dromaeosauridae), articulated left distal hindlimb (EME PV.313) in lateral view (Sebeş = Şard Formation, Sebeş-Glod, southewestern Transylvanian Basin; photo by Mick Ellison) I Zalmoxes robustus (Ornithopoda, Rhabdodontidae), right dentary (NHMUK R.3407) in medial view (Sînpetru Formation, Sînpetru, Haţeg Basin) J Telmatosaurus transsylvanicus (Hadrosauria), right maxilla (MFGI unnumbered) in lateral view (Sînpetru Formation, Sînpetru, Haţeg Basin) K Indeterminate nodosaurid – Struthiosaurus transylvanicus or new taxon – (Ankylosauria, Nodosauridae), isolated tooth (LPB (FGGUB) R.2182) in medial view (Sînpetru Formation, Sînpetru, Haţeg Basin) L Barbatodon transylvanicus (Multituberculata, Kogaionidae), right maxilla (LPB (FGGUB) M.1635) in medial view (Sînpetru Formation, Pui, Haţeg Basin). Scale bars equal 1 mm in A, B; 5 mm in K; 1 cm in G, L; 2 cm in D; and 5 cm in C, E, F, H, I, J.

Representative taxa from the latest Campanian–Maastrichtian faunas from Transylvania, western Romania. A–B Nidophis insularis (Serpentes, Madtsoiidae), articulated vertebrae (LPB (FGGUB) v.547/2) in left lateral (A) and dorsal (B) views (Densuş-Ciula Formation, Tuştea, Haţeg Basin; photo by Ştefan Vasile) C Allodaposuchus precedens (Eusuchia, ?Hylaeochampsidae), skull (PSMUBB V 438) in dorsal view (Sebeş = Şard Formation, Oarda de Jos, southwestern Transylvanian Basin; photo by Vlad Codrea/Massimo Delfino) D Theriosuchus sympiestodon (Mesoeucrocodylia, Atoposauridae), right maxilla (MCDRD 793) in lateral view (Sînpetru Formation, Sînpetru, Haţeg Basin) E–F Indeterminate titanosaur (?Magyarosaurus dacus) (Sauropoda, Titanosauria), isolated osteoderm (LPB (FGGUB) R.1410) in dorsal (E) and lateral (F) views (Sînpetru Formation, Sînpetru, Haţeg Basin) G Indeterminate ornithuran bird (Aves, Ornithurae), incomplete left tibiotarsus (LPB (FGGUB) R.1902) in anterior view (Densuş-Ciula Formation, Vălioara, Haţeg Basin) H Balaur bondoc (Theropoda, Dromaeosauridae), articulated left distal hindlimb (EME PV.313) in lateral view (Sebeş = Şard Formation, Sebeş-Glod, southewestern Transylvanian Basin; photo by Mick Ellison) I Zalmoxes robustus (Ornithopoda, Rhabdodontidae), right dentary (NHMUK R.3407) in medial view (Sînpetru Formation, Sînpetru, Haţeg Basin) J Telmatosaurus transsylvanicus (Hadrosauria), right maxilla (MFGI unnumbered) in lateral view (Sînpetru Formation, Sînpetru, Haţeg Basin) K Indeterminate nodosaurid – Struthiosaurus transylvanicus or new taxon – (Ankylosauria, Nodosauridae), isolated tooth (LPB (FGGUB) R.2182) in medial view (Sînpetru Formation, Sînpetru, Haţeg Basin) L Barbatodon transylvanicus (Multituberculata, Kogaionidae), right maxilla (LPB (FGGUB) M.1635) in medial view (Sînpetru Formation, Pui, Haţeg Basin). Scale bars equal 1 mm in A, B; 5 mm in K; 1 cm in G, L; 2 cm in D; and 5 cm in C, E, F, H, I, J.

Roumanie Densuş-Ciula Sebeş Sînpetru +9
The Naturmuseum Senckenberg in Frankfurt is the second largest museum of natural history in Germany. It is particularly popular with children, who enjoy the extensive collection of dinosaur skeletons: Senckenberg boasts the largest exhibition of large dinosaurs in Europe. One particular treasure is a dinosaur fossil with unique, preserved scaled skin. The museum contains the world's largest and most diverse collection of stuffed birds with about 2000 specimens.

The Naturmuseum Senckenberg in Frankfurt is the second largest museum of natural history in Germany. It is particularly popular with children, who enjoy the extensive collection of dinosaur skeletons: Senckenberg boasts the largest exhibition of large dinosaurs in Europe. One particular treasure is a dinosaur fossil with unique, preserved scaled skin. The museum contains the world's largest and most diverse collection of stuffed birds with about 2000 specimens.

musée Allemagne fossile spécimen +4
Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA.
This is a remarkable complete skeleton of the small early theropod Coelophysis.  It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard".  This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994).
Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic
Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA


Some info. from:
Hunt, A.P. & S.G. Lucas.  1991.  Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA).  Paläontologische Zeitschrift  65: 191-198.
Schwartz, H.L. & D.D. Gillette.  1994.  Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico.  Journal of Paleontology 68: 1118-1130.


Theropod were small to large, bipedal dinosaurs.  Almost all known members of the group were carnivorous (predators and/or scavengers).  They represent the ancestral group to the birds, and some theropods are known to have had feathers.  Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.
Taxons Coelophysis

Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA. This is a remarkable complete skeleton of the small early theropod Coelophysis. It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard". This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994). Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA Some info. from: Hunt, A.P. & S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65: 191-198. Schwartz, H.L. & D.D. Gillette. 1994. Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico. Journal of Paleontology 68: 1118-1130. Theropod were small to large, bipedal dinosaurs. Almost all known members of the group were carnivorous (predators and/or scavengers). They represent the ancestral group to the birds, and some theropods are known to have had feathers. Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.

plume prédateur Mexique États-Unis +18
Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA.
This is a remarkable complete skeleton of the small early theropod Coelophysis.  It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard".  This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994).
Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic
Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA


Some info. from:
Hunt, A.P. & S.G. Lucas.  1991.  Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA).  Paläontologische Zeitschrift  65: 191-198.
Schwartz, H.L. & D.D. Gillette.  1994.  Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico.  Journal of Paleontology 68: 1118-1130.


Theropod were small to large, bipedal dinosaurs.  Almost all known members of the group were carnivorous (predators and/or scavengers).  They represent the ancestral group to the birds, and some theropods are known to have had feathers.  Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.
Taxons Coelophysoidea

Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA. This is a remarkable complete skeleton of the small early theropod Coelophysis. It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard". This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994). Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA Some info. from: Hunt, A.P. & S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65: 191-198. Schwartz, H.L. & D.D. Gillette. 1994. Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico. Journal of Paleontology 68: 1118-1130. Theropod were small to large, bipedal dinosaurs. Almost all known members of the group were carnivorous (predators and/or scavengers). They represent the ancestral group to the birds, and some theropods are known to have had feathers. Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.

plume prédateur Mexique États-Unis +18
Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA.
This is a remarkable complete skeleton of the small early theropod Coelophysis.  It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard".  This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994).
Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic
Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA


Some info. from:
Hunt, A.P. & S.G. Lucas.  1991.  Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA).  Paläontologische Zeitschrift  65: 191-198.
Schwartz, H.L. & D.D. Gillette.  1994.  Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico.  Journal of Paleontology 68: 1118-1130.


Theropod were small to large, bipedal dinosaurs.  Almost all known members of the group were carnivorous (predators and/or scavengers).  They represent the ancestral group to the birds, and some theropods are known to have had feathers.  Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.
Taxons Coelophysidae

Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA. This is a remarkable complete skeleton of the small early theropod Coelophysis. It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard". This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994). Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA Some info. from: Hunt, A.P. & S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65: 191-198. Schwartz, H.L. & D.D. Gillette. 1994. Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico. Journal of Paleontology 68: 1118-1130. Theropod were small to large, bipedal dinosaurs. Almost all known members of the group were carnivorous (predators and/or scavengers). They represent the ancestral group to the birds, and some theropods are known to have had feathers. Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.

plume prédateur Mexique États-Unis +18
Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA.
This is a remarkable complete skeleton of the small early theropod Coelophysis.  It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard".  This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994).
Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic
Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA


Some info. from:
Hunt, A.P. & S.G. Lucas.  1991.  Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA).  Paläontologische Zeitschrift  65: 191-198.
Schwartz, H.L. & D.D. Gillette.  1994.  Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico.  Journal of Paleontology 68: 1118-1130.


Theropod were small to large, bipedal dinosaurs.  Almost all known members of the group were carnivorous (predators and/or scavengers).  They represent the ancestral group to the birds, and some theropods are known to have had feathers.  Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.
Taxons Coelophysinae

Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA. This is a remarkable complete skeleton of the small early theropod Coelophysis. It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard". This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994). Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA Some info. from: Hunt, A.P. & S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65: 191-198. Schwartz, H.L. & D.D. Gillette. 1994. Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico. Journal of Paleontology 68: 1118-1130. Theropod were small to large, bipedal dinosaurs. Almost all known members of the group were carnivorous (predators and/or scavengers). They represent the ancestral group to the birds, and some theropods are known to have had feathers. Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.

plume prédateur Mexique États-Unis +18
Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA.
This is a remarkable complete skeleton of the small early theropod Coelophysis.  It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard".  This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994).
Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic
Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA


Some info. from:
Hunt, A.P. & S.G. Lucas.  1991.  Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA).  Paläontologische Zeitschrift  65: 191-198.
Schwartz, H.L. & D.D. Gillette.  1994.  Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico.  Journal of Paleontology 68: 1118-1130.


Theropod were small to large, bipedal dinosaurs.  Almost all known members of the group were carnivorous (predators and/or scavengers).  They represent the ancestral group to the birds, and some theropods are known to have had feathers.  Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.
Taxons Podokesaurinae

Coelophysis bauri (Cope, 1887) theropod dinosaur from the Triassic of New Mexico, USA. This is a remarkable complete skeleton of the small early theropod Coelophysis. It comes from a nearly monospecific concentration of numerous complete to disarticulated skeletons in reddish-colored fluvial siltstones, often called a "Coelophysis graveyard". This occurrence has been interpreted as a carcass-jammed channel filling following mass mortality of dinosaurs by regional drought (see Schwartz & Gillette, 1994). Stratigraphy: Rock Point Member, Chinle Formation, Upper Triassic Locality: Whitaker Quarry (Coelophysis Quarry), Ghost Ranch, Rio Arriba County, northern New Mexico, USA Some info. from: Hunt, A.P. & S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65: 191-198. Schwartz, H.L. & D.D. Gillette. 1994. Geology and taphonomy of the Coelophysis Quarry, Upper Triassic Chinle Formation, Ghost Ranch, New Mexico. Journal of Paleontology 68: 1118-1130. Theropod were small to large, bipedal dinosaurs. Almost all known members of the group were carnivorous (predators and/or scavengers). They represent the ancestral group to the birds, and some theropods are known to have had feathers. Some of the most well known dinosaurs to the general public are theropods, such as Tyrannosaurus, Allosaurus, and Spinosaurus.

plume prédateur Mexique États-Unis +18
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Actualités

Un reptile momifié vieux de 289 millions d'années révèle comment la respiration a commencé sur terre
oiseau mammifères
Un reptile momifié remarquablement préservé datant d’il y a 289 millions d’années est en train de réécrire ce que nous savons sur la façon dont les animaux respiraient pour la première fois sur terre. Cette minuscule créature, Captorhinus aguti, révèle la première version connue du système respiratoire actionné par les côtes utilisé par les reptiles, les oiseaux et les mammifères modernes – une innovation cruciale qui a aidé les vertébrés à prospérer en dehors de l'eau.
23/04/2026 sciencedaily ⚙ Traduction automatique
Des scientifiques ont recréé un nid de dinosaure pour résoudre un mystère vieux de 70 millions d'années
nid Dinosauria Oviraptor oiseau
Les scientifiques ont recréé un nid d'oviraptors grandeur nature pour comprendre comment ces dinosaures ont fait éclore leurs œufs. Leurs expériences ont montré que le parent ne pouvait probablement pas chauffer tous les œufs directement, ce qui signifie que la lumière du soleil jouait un rôle clé. Ce chauffage inégal pourrait faire éclore les œufs d’un même nid à des moments différents. Les résultats suggèrent que les oviraptors utilisaient une méthode d’incubation hybride contrairement aux oiseaux modernes.
19/03/2026 sciencedaily ⚙ Traduction automatique
Ces dinosaures avaient des ailes mais ne pouvaient pas voler
plume fossile Anchiornis Dinosauria oiseau
Certains dinosaures à plumes ont peut-être brièvement pris leur envol, pour y renoncer plus tard. En étudiant des fossiles rares avec des plumes préservées, les chercheurs ont découvert un indice surprenant caché dans les schémas de mue, révélant qu’Anchiornis ne pouvait probablement pas voler du tout. Au lieu du remplacement soigné et symétrique des plumes observé chez les oiseaux volants, ces dinosaures ont présenté une mue désordonnée et irrégulière, ce que seuls les animaux incapables de voler présentent.
18/03/2026 sciencedaily ⚙ Traduction automatique
Ce dinosaure de 2 livres réécrit ce que les scientifiques savent de l'évolution
fossile Alnashetri Alvarezsauria Dinosauria oiseau évolution squelette
Un squelette de dinosaure presque complet découvert en Patagonie aide les scientifiques à percer le mystère des alvarezsaures, un groupe étrange de dinosaures ressemblant à des oiseaux. Le fossile d'Alnashetri cerropoliciensis révèle que ces animaux sont devenus minuscules avant de développer leurs caractéristiques spécialisées ultérieures, telles que des bras tronqués et des adaptations mangeuses de fourmis. Pesant moins de deux livres, le dinosaure est l’un des plus petits connus d’Amérique du Sud.
10/03/2026 sciencedaily ⚙ Traduction automatique
Cet étrange petit dinosaure oblige à repenser l'évolution
os dent métabolisme Dinosauria Foskeia anatomie oiseau évolution mammifères étude crâne
Un petit dinosaure nouvellement identifié, Foskeia pelendonum, bouleverse les idées reçues de longue date sur l'évolution des dinosaures herbivores. Même si les adultes adultes étaient remarquablement petits et légers, leur anatomie était tout sauf simple : elles présentaient un crâne bizarre et hautement spécialisé et des traits évolutifs inattendus. Des études osseuses détaillées montrent que ces dinosaures ont mûri rapidement avec un métabolisme semblable à celui des oiseaux ou des mammifères, tandis que leurs dents et leur posture suggèrent une vie rapide et agile dans des forêts denses.
03/02/2026 sciencedaily ⚙ Traduction automatique
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