Scientists at Bournemouth University (BU) have solved a 150-year-old mystery into the identity of an extinct giant crane that lived in Europe over 20,000 years ago.
The extinct, giant, primeval crane was named Grus primigenia in the 19th century by French biologist Alphonse Milne-Edwards from bone fragments found in caves in the south of France. These were dated to the end of the last ice age. Since the discovery, it has been widely believed that these bones were from an extinct species of giant crane.
However, a new study led by Dr John Stewart, Professor of Evolutionary Palaeoecology at BU and leader of the research team revealed that the bones are in fact larger versions of the current common crane we see in Europe today and not from a separate, extinct species of crane.
Dr Stewart said: "We suspected that these large cranes were not extinct and instead represented larger, modern European common cranes. We believe that the reason for the mistaken identity was that cranes have large males and smaller females and we think this contributed to previous speculation that there were two different species - the living, common crane we see today and the extinct, larger species."
The study, carried out in partnership with the Centre for Palaeogenetics in Stokholm, Sweden used ancient DNA samples from 18 crane bones discovered in England, Wales, France, Germany and the Balearic Islands. The genetic material from the bones was extracted to identify species.
Dr Stewart continued: "Previous studies had merely used the size and shape of the bones to attempt to understand these large birds. The use of DNA analysis has given us a more accurate picture of what they represent."
Dr Stewart and the research team at BU aim to conduct further research into why these cranes decreased in size. "The challenge going forwards is to investigate the reason for the cranes decrease in size. Wetland drainage and human land use changes are what we suspect, but more work is needed to resolve that." Dr Steward added.
The study also highlights the issue of identifying extinct birds in general from their bones. It may be that other extinct bird species which have been identified solely using size differences are problematic. An ancient DNA investigation may be required to confirm these identities.
"While it is true that many species of birds are vulnerable to human actions today, it may be that we have overestimated the number of extinctions in the past," said Dr Stewart. "Some of these may instead represent size changes to living species" he concluded.
