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This is Scientific American's 60-Second Science. I am Adam Hamterture, got a minute?

What's sixteen feet tall and 9,550 years old? It’s the world's oldest tree. The worn and weathered spruce grows in Sweden's windswept tundra¹. But, until recently, well, recent to the tree at least, it barely resembled a tree at all. Before this last warm century, the spruce grew more like a shrub² to survive the harsh conditions of its cold landscape. But rising temperatures convinced the tree to give up its shabby lifestyle, shed the majority of its needles and go with the single-trunk look.Researchers from Sweden's Umea University found the tree growing amid the remains³ of four generations of spruce dating from 375 to well over 9,000 years old. Spruce trees can clone themselves by sending new trees up through the ground from established roots. When the scientists tested the current tree, they found it was genetically⁴ identical with the remains of all four previous generations. Researchers are excited about having a 10,000-year-long case study of how past climate changes affected⁵ plant growth and productivity. It’s a finding sure to spruce up all of botany.

Thanks for the minute for Scientific American's 60-Second Science. I am Adam Hamterture.