The evolution of mammal-like crocodyliforms in the Cretaceous Period of Gondwana.

Title

The evolution of mammal-like crocodyliforms in the Cretaceous Period of Gondwana.

Creator

O'Connor Patrick M; Sertich Joseph J W; Stevens Nancy J; Roberts Eric M; Gottfried Michael D; Hieronymus Tobin L; Jinnah Zubair A; Ridgely Ryan; Ngasala Sifa E; Temba Jesuit

Publisher

Nature

Date

2010
2010-08-05

Description

Fossil crocodyliforms discovered in recent years have revealed a level of morphological and ecological diversity not exhibited by extant members of the group. This diversity is particularly notable among taxa of the Cretaceous Period (144–65 million years ago) recovered from former Gondwanan landmasses. Here we report the discovery of a new species of Cretaceous notosuchian crocodyliform from the Rukwa Rift Basin of southwestern Tanzania. This small-bodied form deviates significantly from more typical crocodyliform craniodental morphologies, having a short, broad skull, robust lower jaw, and a dentition with relatively few teeth that nonetheless show marked heterodonty. The presence of morphologically complex, complementary upper and lower molariform teeth suggests a degree of crown–crown contact during jaw adduction that is unmatched among known crocodyliforms, paralleling the level of occlusal complexity seen in mammals and their extinct relatives. The presence of another small-bodied mammal-like crocodyliform in the Cretaceous of Gondwana indicates that notosuchians probably filled niches and inhabited ecomorphospace that were otherwise occupied by mammals on northern continents. [ABSTRACT FROM AUTHOR]

Subject

TANZANIA; ANIMAL classification; ANIMAL diversity; ANIMAL species; CRETACEOUS paleoecology; EVOLUTION (Biology); FOSSIL crocodylidae; TAXONOMY

Identifier

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

748–751

Issue

7307

Volume

466

Citation

O'Connor Patrick M; Sertich Joseph J W; Stevens Nancy J; Roberts Eric M; Gottfried Michael D; Hieronymus Tobin L; Jinnah Zubair A; Ridgely Ryan; Ngasala Sifa E; Temba Jesuit, “The evolution of mammal-like crocodyliforms in the Cretaceous Period of Gondwana.,” NEOMED Bibliography Database, accessed March 28, 2024, https://neomed.omeka.net/items/show/5743.