The late Cenozoic passerine avifauna from Rackham’s Roost Site, Riversleigh, Australia

A remarkable fossil discovery at Rackham’s Roost Site, part of the Riversleigh World Heritage Area, reveals the oldest records of five passerine bird families in Australia and globally. These fossils, dating back to the late Cenozoic, include the first known remains of Maluridae (fairywrens), Acanthizidae (acanthizid warblers), Pomatostomidae (Australo-Papuan babblers), Petroicidae (Australasian robins), and Estrildidae (estrildid finches). The study also identifies diagnostic postcranial characters for these families, aiding future morphological and phylogenetic research. The fossil assemblage suggests that the Ghost Bat, now endangered, was the primary accumulator of these remains, hinting at its dietary habits in an open woodland environment with a grassy understorey. This finding provides critical insights into the avian biodiversity and palaeoenvironment of northern Australia during the early Pleistocene.

Nguyen, J. M. T., Hand, S. J., & Archer, M. (2016). The late Cenozoic passerine avifauna from Rackham’s Roost Site, Riversleigh, Australia. Records of the Australian Museum, 68(5), 201–230. https://doi.org/10.3853/j.2201-4349.68.2016.1668