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

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 ( cf. ) the Australasian Bushlark () a friarbird ( sp.), and the Pechora Pipit ( cf. )

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. ) and a grassbird ( 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. cf. , found in the -bearing layers, was likely part of a scavenging guild that fed on carcasses of alongside vultures ( sp.), giant storks (), komodo dragons (), and probably as well.