What is the oldest plant living right now?
A: The oldest living plant individual — King's holly (Lomatia tasmanica) — is 43,600 years old.
Determining that King's holly is indeed the oldest living plant reads like a detective story.
In 1937, an odd-ball hermit, bushman, miner, scientific collector, and generally neat guy, named Deny King discovered the plant while mining tin by hand in the remote southwest of Tasmania. The plant was named in King's honor.
Tasmania's leading botanist, Winifred Curtis, described the plant in 1967 and had a hunch it was old. Scientists searched hard for other individuals but didn't find any.
The sole remaining individual straggles out in a line of 500 clone bushes, nearly a mile long (1.2 km). It reproduces itself by dropping branch pieces that take root. In the cold wet gloom of Tasmanian gullies, such propagation is slow. The shiny-leaf plant bears pink flowers but neither fruit nor seeds. It can only reproduce itself by cloning genetically identical bushes.
The plant has no choice. It must produce clones instead of seed since it has three sets of chromosomes (a triploid) instead of the normal two and is, therefore, sterile. When an old bush falls down, the individual lives on through its clones.
Investigators found fossil leaf fragments identical to the living bush 5.3 miles (8.5 km) away. University of Tasmania scientists carbon dated the fossils as 43,600 years old. The fossil cell structure and shape are the same as the living plant's, which can only mean the ancient plant was triploid also.
Moreover, triploidy is so rare that it's unlikely the trait occurred twice in the same species. Thus, the fossil remnants came from the same individual as the plant living now. Over 43,000 years ago (about the time Homo sapiens displaced Neanderthal man), the ancient Tasmanian shrub suckered new shrubs that eventually suckered the oldest living plant.
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