A brand new College of Otago-led examine has uncovered the origins of a mysterious lineage of mergansers in Aotearoa New Zealand.
Mergansers are riverine and coastal fish-eating geese predominantly discovered within the Northern Hemisphere, nonetheless there are a couple of uncommon species from the Southern Hemisphere.
They’re the critically endangered Brazilian merganser (Mergus octosetaceus) and at the very least two extinct species identified to be from New Zealand’s Auckland and Chatham Islands (Mergus australis and Mergus milleneri, respectively).
The examine’s lead creator Affiliate Professor Nic Rawlence, Director of the Otago Palaeogenetics Laboratory, says the evolutionary historical past of mergansers in New Zealand has been shrouded in thriller because the extinction of the Auckland Island merganser, the final surviving inhabitants, in 1902.
“There may be not even a deep-time fossil file of those birds within the Southern Hemisphere,” Affiliate Professor Rawlence says.
Till now, the evolutionary relationship between the Southern Hemisphere mergansers, when their ancestors arrived within the area, and from the place, have been unknown.
The examine’s findings, revealed within the Zoological Journal of the Linnean Society, present mergansers arrived within the New Zealand area at the very least seven million years in the past from the Northern Hemisphere, in a separate colonisation occasion to that which led to the Brazilian merganser.
Affiliate Professor Rawlence says this can be a vital discovery.
“It reveals an growing variety of New Zealand’s birds do not hail from Australia, with extra cosmopolitan hyperlinks with Madagascar, Africa, South America, and now the Northern Hemisphere.
“The grandfather of New Zealand palaeontology, Sir Charles Fleming, hypothesised this again within the Nineteen Sixties, lengthy earlier than the appearance of genetics, and it is solely now that genetics and palaeontology are catching up.”
The collaborative analysis, which additionally concerned scientists from Manaaki Whenua Landcare Analysis, the Museum of New Zealand Te Papa Tongarewa, and the College of Adelaide, used state-of-the-art historical DNA strategies to extract the DNA from historic specimens of the extinct Auckland Island merganser and the critically endangered Brazilian merganser and “went fishing for his or her DNA.”
“We sequenced the mitochondrial genome of those species and reconstructed the household tree of mergansers and when their ancestors arrived within the area,” he says.
“Additional analysis by our lab is hoping to find out when and the way mergansers diversified throughout the New Zealand area, together with on the mainland, and Auckland and Chatham Islands.”
Affiliate Professor Rawlence believes future palaeontological and historical DNA analysis within the Southern Hemisphere will unearth extra surprising lineages.
