Dataset Information

High-latitude neonate and perinate ornithopods from the mid-Cretaceous of southeastern Australia.

ABSTRACT: Dinosaurs were remarkably climate-tolerant, thriving from equatorial to polar latitudes. High-paleolatitude eggshells and hatchling material from the Northern Hemisphere confirms that hadrosaurid ornithopods reproduced in polar regions. Similar examples are lacking from Gondwanan landmasses. Here we describe two non-iguanodontian ornithopod femora from the Griman Creek Formation (Cenomanian) in New South Wales, Australia. These incomplete proximal femora represent the first perinatal ornithopods described from Australia, supplementing neonatal and slightly older 'yearling' specimens from the Aptian-Albian Eumeralla and Wonthaggi formations in Victoria. While pseudomorphic preservation obviates histological examination, anatomical and size comparisons with Victorian specimens, which underwent previous histological work, support perinatal interpretations for the Griman Creek Formation femora. Estimated femoral lengths (37?mm and 45?mm) and body masses (113-191?g and 140-236?g), together with the limited development of features in the smallest femur, suggest a possible embryonic state. Low body masses (<1?kg for 'yearlings' and ~20?kg at maturity) would have precluded small ornithopods from long-distance migration, even as adults, in the Griman Creek, Eumeralla, and Wonthaggi formations. Consequently, these specimens support high-latitudinal breeding in a non-iguanodontian ornithopod in eastern Gondwana during the early Late Cretaceous.

SUBMITTER: Kitchener JL

PROVIDER: S-EPMC6925213 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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High-latitude neonate and perinate ornithopods from the mid-Cretaceous of southeastern Australia.

Kitchener Justin L JL Campione Nicolás E NE Smith Elizabeth T ET Bell Phil R PR

Scientific reports 20191220 1

Dinosaurs were remarkably climate-tolerant, thriving from equatorial to polar latitudes. High-paleolatitude eggshells and hatchling material from the Northern Hemisphere confirms that hadrosaurid ornithopods reproduced in polar regions. Similar examples are lacking from Gondwanan landmasses. Here we describe two non-iguanodontian ornithopod femora from the Griman Creek Formation (Cenomanian) in New South Wales, Australia. These incomplete proximal femora represent the first perinatal ornithopods ...[more]

PMID: 31862946

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Dataset Information

High-latitude neonate and perinate ornithopods from the mid-Cretaceous of southeastern Australia.

Publications

High-latitude neonate and perinate ornithopods from the mid-Cretaceous of southeastern Australia.

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