When the first Polynesian settlers arrived on the shores of New Zealand somewhere between 1200 and 1300 CE, they would have been met by the vision of thousands of prehistoric sealions and southern elephant seals lining the sandy shores of a land untouched by humans. It’s an image hard to imagine today, particularly as – over the centuries – the elephant seal has become a species that has simply fallen outside of the New Zealand biological heritage, forced southwards, new research has shown, by climate change. Yet, according to a new study from scientists at Griffith University, it’s only some 400 years ago that New Zealand beaches were once “heaving” with these colossal, southern elephant seals. These findings have prompted researchers to liken southern elephant seals to the ‘canary in the coal mine’ for the Southern Ocean, offering insight into how the ecosystem may react to future climate change and human impact. Joint senior author Associate Professor Nic Rawlence, director of the Otago Palaeogenetics Laboratory at Griffith University, said: “At the time of human arrival in New Zealand, you would be hard pressed to find room on the beaches, with fur seals on the rocky headlands, prehistoric sealions, and elephant seals on the sand… and lots of penguins.” Led by postgraduate students Andrew Berg of the University of Sydney, and Otago’s Megan Askew, the study – undertaken by a group of international researchers – has recently been published in the journal Global Change Biology . To conduct their study, the team used palaeogenetic techniques – a process that involves extracting and analysing DNA from ancient biological materials like bones, teeth, and sediments – on specimens dating back thousands of years from New Zealand, Tasmania, and Antarctica to show that southern elephant seals used to be spread across the entire […]
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