Ancient DNA study resolves the taxonomic status of the extinct large Palaearctic crane Grus primigenia Milne-Edwards, 1871 (Aves: Gruiformes: Gruidae)

Abstract

The identity of the extinct large crane Grus primigenia has been debated for over 150 years. Alternative interpretations suggest that such large crane remains represent extant cranes such as the sarus crane Antigone antigone, the Siberian white crane Leucogeranus leucogeranus or simply larger individuals of common crane Grus grus. Morphometrics has shown that the common crane is sexually dimorphic today with larger males and smaller females. We analysed cranes from the Late Pleistocene to Late Holocene and found that the lack of smaller female-sized craneremains suggests that G. grus may have reduced in size over time. In the present study, we successfully performed an ancient DNA analysis to assess the phylogenetic identity of 18 crane remains from the Late Pleistocene of Spain and France and the Late Holocene of Britain and Germany. All remains were identified as G. grus. These ancient cranes included individuals that were larger than modern G. grus and ones that conformed in size with common crane today. Ancient DNA-based sexing found that all the bones that were larger than those of modern males were male, while specimens the size of modern males included ancient females. This confirmed that the ancient cranes were sexually dimorphic G. grus that have become smaller since the Saxon times (884 yr BP).