The ‘world’s loneliest tree’ lives on on Campbell Island, New Zealand – 170 miles away from its nearest neighbor. New Zealand governor Lord Ranfurly planted the Sitka spruce on the island sometime in the early 20th century, and researchers now believe it holds clues about the Anthropocene Epoch. After completing a thorough analysis of the tree, researchers set a potential start date for the geological age in which humans became the dominant influence on the environment.
In a piece for The Conversation, Chris Turney and Jonathan Palmer of the University of New South Wales and Mark Maslin of University College London shared work revealing how the world’s loneliest tree might help us determine a potential start date for the Anthropocene. The wood of the tree recorded the radiocarbon generated by above-ground atomic bomb tests, and its layers reveal a peak in 1965, according to the scientists.
The spike in radioactive elements generated from those thermonuclear bomb tests has been a contender for defining the Anthropocene’s beginning, according to the scientists, but until now most of the records have been collected in the Northern Hemisphere. They said, “To demonstrate a truly global human impact requires a signal from a remote, pristine location in the Southern Hemisphere that occurs at the same time as the north.”
The world’s loneliest tree helped provide that signal. Detailed study of the tree’s year-by-year growth reveals a spike in radioactive elements between October and December 1965. The scientists said, “This spruce has demonstrated unequivocally that humans have left an impact on the planet, even in the most pristine of environments, that will be preserved in the geological record for tens of millennia and beyond.” In other words, according to this research, the Anthropocene officially began in 1965.
The journal Scientific Reports published the research online this week; scientists at institutions in Australia, New Zealand, the United Kingdom, the United States, and Germany contributed.
Via The Conversation