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Paleontologists working in Brazil have uncovered the fossil of an ornithuromorph bird that lived during the Early Cretaceous epoch.
Life reconstruction ofKaririavis mater. Image credit: Divulgação.
Kaririavis materlived in what is now Brazil some 115 million years ago (Early Cretaceous epoch).
“Kaririavis materlived during the Cretaceous period, when the supercontinent Gondwana — which included the South America, Africa, Australia, Antarctica and India — was splitting,” said Dr. Ismar de Souza Carvalho, a paleontologist at the Universidade Federal do Rio de Janeiro and the Universidade de Coimbra, and colleagues.
The new species is a member ofOrnithuromorpha, a large group of birds thatcontainsall extinct and living species but not Mesozoic enantiornithes.
“It had both primitive and modern morphological characteristics, making its behavior and ecological niche still mysterious,” the paleontologists said.
“It had coarse feet, very stout toe phalanges, and a claw on the second toe, very curved and proportionately large for its size, unlike those found in most ornithuromorphs, which had slender feet and slender toes.”
The fossilized remains ofKaririavis mater— an isolated right foot with some feathers — were recovered from the Crato Formation at Pedra Branca Mine, in Brazil’s Ceará state.
Its unique foot conformation indicates that it may belong to an unknown ornithuromorph clade with some cursory similarities to living flightless ratites, such as the rhea or the ostrich.
The 115-million-year-old fossilized foot ofKaririavis mater. Image credit: Carvalhoet al., doi: 10.1080/02724634.2021.1988623.
According to the scientists,Kaririavis materis the earliest known member of Ornithuromorpha from Gondwana and the oldest fossil bird from South America.
“The presence of Early Cretaceous ornithuromorphs in Brazil indicates that the clade was widespread in Gondwana during the Mesozoic,” they said.
“The discovery brings light to the discussion on the origin of birds on Earth,” said Professor José Xavier Neto, a researcher at the Universidade Federal do Ceará.
“China is the world’s most important source of primitive bird fossils. But, with this unprecedented discovery, the place of origin of the birds is now not clear and definitive: did the birds appear in China and then fly to Brazil or did they appear in Brazil and then fly to China?”
The discovery ofKaririavis materis described in apaperpublished online in theJournal of Vertebrate Paleontology.
2021年12月04日 10点12分
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Life reconstruction ofKaririavis mater. Image credit: Divulgação.Kaririavis materlived in what is now Brazil some 115 million years ago (Early Cretaceous epoch).
“Kaririavis materlived during the Cretaceous period, when the supercontinent Gondwana — which included the South America, Africa, Australia, Antarctica and India — was splitting,” said Dr. Ismar de Souza Carvalho, a paleontologist at the Universidade Federal do Rio de Janeiro and the Universidade de Coimbra, and colleagues.
The new species is a member ofOrnithuromorpha, a large group of birds thatcontainsall extinct and living species but not Mesozoic enantiornithes.
“It had both primitive and modern morphological characteristics, making its behavior and ecological niche still mysterious,” the paleontologists said.
“It had coarse feet, very stout toe phalanges, and a claw on the second toe, very curved and proportionately large for its size, unlike those found in most ornithuromorphs, which had slender feet and slender toes.”
The fossilized remains ofKaririavis mater— an isolated right foot with some feathers — were recovered from the Crato Formation at Pedra Branca Mine, in Brazil’s Ceará state.
Its unique foot conformation indicates that it may belong to an unknown ornithuromorph clade with some cursory similarities to living flightless ratites, such as the rhea or the ostrich.
The 115-million-year-old fossilized foot ofKaririavis mater. Image credit: Carvalhoet al., doi: 10.1080/02724634.2021.1988623.According to the scientists,Kaririavis materis the earliest known member of Ornithuromorpha from Gondwana and the oldest fossil bird from South America.
“The presence of Early Cretaceous ornithuromorphs in Brazil indicates that the clade was widespread in Gondwana during the Mesozoic,” they said.
“The discovery brings light to the discussion on the origin of birds on Earth,” said Professor José Xavier Neto, a researcher at the Universidade Federal do Ceará.
“China is the world’s most important source of primitive bird fossils. But, with this unprecedented discovery, the place of origin of the birds is now not clear and definitive: did the birds appear in China and then fly to Brazil or did they appear in Brazil and then fly to China?”
The discovery ofKaririavis materis described in apaperpublished online in theJournal of Vertebrate Paleontology.
