Late Pleistocene songbirds of Liang Bua (Flores, Indonesia); the first fossil passerine fauna described from Wallacea

• Published in: PeerJ
• Main Authors: Meijer, Hanneke J.M., Awe Due, Rokus, Sutikna, Thomas, Saptomo, Wahyu, Jatmiko, Wasisto, Sri, Tocheri, Matthew W., Mayr, Gerald
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2017
• Subjects: Passeriformes; Southeast Asia; Wallacea; Passerines; Avifauna; Aves; Pechora
• Online Access: https://repository.publisso.de/resource/frl:6409088; https://doi.org/10.7717/peerj.3676; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5563437/; https://peerj.com/articles/3676/#supplemental-information

BACKGROUND: Passerines (Aves: Passeriformes) dominate modern terrestrial bird communities yet their fossil record is limited. Liang Bua is a large cave on the Indonesian island of Flores that preserves Late Pleistocene–Holocene deposits (∼190 ka to present day). Birds are the most diverse faunal group at Liang Bua and are present throughout the stratigraphic sequence. METHODS: We examined avian remains from the Late Pleistocene deposits of Sector XII, a 2 × 2 m area excavated to about 8.5 m depth. Although postcranial passerine remains are typically challenging to identify, we found several humeral characters particularly useful in discriminating between groups, and identified 89 skeletal elements of passerines. RESULTS: At least eight species from eight families are represented, including the Large-billed Crow (Corvus cf. macrorhynchos), the Australasian Bushlark (Mirafra javanica), a friarbird (Philemon sp.), and the Pechora Pipit (Anthus cf. gustavi). DISCUSSION: These remains constitute the first sample of fossil passerines described in Wallacea. Two of the taxa no longer occur on Flores today; a large sturnid (cf. Acridotheres) and a grassbird (Megalurus sp.). Palaeoecologically, the songbird assemblage suggests open grassland and tall forests, which is consistent with conditions inferred from the non-passerine fauna at the site. Corvus cf. macrorhynchos, found in the Homo floresiensis-bearing layers, was likely part of a scavenging guild that fed on carcasses of Stegodon florensis insularis alongside vultures (Trigonoceps sp.), giant storks (Leptoptilos robustus), komodo dragons (Varanus komodoensis), and probably H. floresiensis as well.