| Rahonavis Temporal range: Late Cretaceous | |
|---|---|
| |
| Life restoration of Rahonavis by Gabriel N. U. | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| clade: | Dinosauria |
| Suborder: | Theropoda |
| Genus: | †Rahonavis Forster et al., 1998b |
| Type species | |
| †Rahonavis ostromi (Forster et al., 1998a) Forster et al., 1998b | |
| Synonyms | |
|
Rahona Forster et al. 1998 non Griveaud 1975 Rahona ostromi Forster et al. 1998a | |
Rahonavis (meaning "cloud menace bird") is a genus of bird-like theropod dinosaur from the Late
Cretaceous of what is now northwestern Madagascar. It is known from a partial skeleton (UA 8656) found by Catherine Forster and colleagues in Maevarano Formation rocks at a quarry near Berivotra, Mahajanga Province.
The name "Rahonavis" means "cloud menace bird", from Malagasy rahona (RA-hoo-na, "cloud" or "menace") + Latin avis "bird". The specific name, Rahonavis ostromi, was named in honor of John Ostrom.
Description[]
Skeletal reconstruction of Rahonavis ostromi
Rahonavis is very bird-like in appearance. It had feathers, could flap its weak wings off the ground slightly, and could glide from tree branch to tree branch. Unlike birds, however, it had teeth, no beak, claws on its arms, and a long tail. It may have been good at repeating sounds other animals made, and could have used it to its advantage in order to keep itself alive.
It was smart in terms of dinosaurs, nad also had large eyes, possibly to help see in the dark during the night. It was small, only about the size of a hawk, but was advanced in terms of dinosaurs. It was so bird-like in fact that scientists are debating whether it was actually a bird more than a dinosaur, and should be classified as one. Rahonavis lived in forested or desert areas, and either scavenged carcasses from dead dinosaurs or ate insects that were around. It lived alongside the region's dominant theropod Majungasaurus and the large sauropod Rapetosaurus.
Size of Rahonavis compared to a human hand
The fossilized remains of Rahonavis were first recovered from the Maevarano Formation in Madagascar in 1995 by a joint expedition of SUNY and the University of Antananarivo, near the village of Berivotra.
Classsification[]
The Late Cretaceous Rahonavis ostromi of Madagascar. Skeletal reconstruction.
Rahonavis has historically been the subject of some uncertainty as to its proper taxonomic position – whether it is a member of the clade Avialae (birds) or a closely related dromaeosaurid. The presence of quill knobs on its ulna (forearm bone) led initially to its inclusion as an avialan; however, the rest of the skeleton is rather typically dromaeosaurid in its attributes. Given the extremely close affinities between basal birds and their dromaeosaurid cousins, along with the possibility that flight may have developed and been lost multiple times among these groups, it has been difficult to place Rahonavis firmly among or outside the birds. Rahonavis could be a close relative to Archaeopteryx, as originally suggested by the describers, and thus a member of the clade Avialae, but while the pelvis shows adaptations to flight similar in function to those of Archaeopteryx, they seem to be independently derived.
In 2020, Rahonavis and the South American Overoraptor were found to be sister taxa in a clade sister to the Avialae.
References[]
- https://www.researchgate.net/figure/The-Late-Cretaceous-Rahonavis-ostromi-of-Madagascar-Skeletal-reconstruction-top-left_fig3_253147221
- https://www.researchgate.net/figure/Life-reconstruction-of-Rahonavis-ostromi-based-on-the-holotype-UA-8656-and-referred_fig31_342545808
- https://www.researchgate.net/figure/Rahona-ostromi-a-new-primitive-bird-from-the-Late-Cretaceous-of-Madagascar-A_fig1_51304358
- https://www.pasttime.org/2013/06/episode-1-field-guide-finding-fossils-in-madagascar/rahonavis-collage-3/
- https://palaeo-electronica.org/content/2020/3060-osteology-of-rahonavis
- https://www.jstor.org/stable/4524040
- https://www.mindat.org/taxon-P64131.html
- https://www.researchgate.net/publication/341735305_New_theropod_dinosaur_from_the_Upper_Cretaceous_of_Patagonia_sheds_light_on_the_paravian_radiation_in_Gondwana
In popular culture[]
- Rahonavis was recently in a documentary Dinosaur Revolution, where it was shown to have been able to repeat and mimic sounds around its environment, ate insects off a Rapetosaurus, and was chased down by a pair of baby Majungasaurus until it used its ventriloquism talent to sound like a large dinosaur and scare off the youngsters.
- It was also in an episode of Planet Dinosaur, where it's driven off by a female Majungasaurus and its babies to scavenge from a Rapetosaurus carcass.
Gallery[]
Rahonavis/Gallery