Assessing the identity of rare historical museum specimens of the extinct blue antelope (Hippotragus leucophaeus) using an ancient DNA approach

Abstract

The blue antelope or bluebuck (Hippotragus leucophaeus) is an extinct species of antelope that lived in South Africa until ca. 1799–1800. Disappearing only 34 years after it was described, it was the first large African mammal species to have become extinct in recent times. Therefore, current scientific knowledge of the blue antelope is limited to museum specimens. However, these are extremely rare and further complicated by uncertainties surrounding their taxonomic status due to morphological similarity with the closely related extant roan antelope (Hippotragus equinus) and sable antelope (Hippotragus niger). A previous study found that only four (out of ten) genetically analysed historical museum specimens could be confirmed as Hippotragus leucophaeus. Here, we analyse a further five potential blue antelope specimens, two of which had been morphologically identified as blue antelope (one from the Natural History Museum (NHM) in London and one from National Museums Scotland in Edinburgh), plus an additional three specimens identified here as candidate blue antelope specimens (from the NHM). We find that only one of the five specimens can be genetically validated as Hippotragus leucophaeus, whereas the other four specimens were identified as H. equinus. Furthermore, using hybridisation capture, we generated two complete mitochondrial genomes for blue antelope specimens that were formerly known only from partial mitochondrial genomes. The diversity analyses including all newly generated genomes further confirm that the mitochondrial nucleotide diversity across this species was low.