Paleontologists have unearthed two fossilized phalanges of an historic carnivorous chook on Seymour Island, Antarctica.
Paleoenvironmental reconstruction of the Early Eocene continental communities of Seymour Island: a big cariamiform chook looking a medium-sized ungulate and observing Notiolofos regueroi, a few marsupials on a tree, Antarctoboenus carlinii flying on the sky, and a flightless Ratites within the again. Image credit score: Carolina Acosta Hospitaleche & Washington Jones, doi: 10.26879/1340.
The historic chook fossils had been discovered within the La Meseta Formation on Seymour Island in West Antarctica.
“These phalanges belonged to a large giant predator, estimated to have had a body mass of around 100 kg,” stated Dr. Carolina Acosta Hospitaleche from the Universidad Nacional de La Plata and Dr. Washington Jones from the Uruguay’s Museo Nacional de Historia Natural.
The specimens are roughly 50 million years old (Early Eocene epoch).
They belong to a kind of phorusrhacid (generally often called terror birds), an extinct household throughout the order Cariamiformes.
“Cariamiformes is an order of mainly terrestrial birds that exhibits a significant past diversification but only two species are living today in South America,” the paleontologists stated.
“Despite the rich fossil record, the phylogenetic and biogeographic relationships within this order remain poorly understood.”
“Within the Cariamiformes, Phorusrhacidae composes the crown-group with Cariamidae, while Idiornithidae and Bathornthidae have been identified recoveredidentified as fossil families.”
The fossilized phalanges of an historic cariamiform chook from Seymour Island, Antarctica. Scale bar – 10 mm. Image credit score: Carolina Acosta Hospitaleche & Washington Jones, doi: 10.26879/1340.
The Antarctic terror birds most certainly preyed on small marsupials and medium-sized ungulates.
“They would be active hunters that fulfilled the role of continental apex predators apparently sub-occupied by mammals in the Paleogene Antarctic communities,” the researchers stated.
“Large Phorusrhacidae-like birds represent a guild hitherto unknown to Antarctica.”
“These findings unequivocally reshape our understanding of the dynamic of Early Eocene Antarctic continental ecosystems.”
The results seem on-line within the journal Palaeontologia Electronica.
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Carolina Acosta Hospitaleche & Washington Jones. 2024. Were terror birds the apex continental predators of Antarctica? New findings within the early Eocene of Seymour Island. Palaeontologia Electronica 27 (1): a13; doi: 10.26879/1340
