One of the oldest ginkgos in Japan, with a 10-meter girth, but at only 700 years old, it’s half the age of some specimens in China. Photo: nippon.com
Why do ginkgos (Ginkgo biloba) live so long? And indeed, some live to be 1,400 years old, possibly even 3,000 years old.
It turns out it’s because they don’t when to die!
Unlike most other plants and, indeed, animals, the ginkgo has no genes for senescence. Other plants have genes for a sort of planned obsolescence (most other tree species are in serious decline after 150 years)… as do birds and mammals, including human beings. Most plants and animals are simply designed to eventually fail. This is called senescence. But scientists could find no difference between the cells of young ginkgo trees and ancient ones, 600 years old. The tree’s ability to photosynthesize, grow leaves, resist disease and even reproduce remain intact, centuries after it germinates.
“Essentially, in relation to the immunity of the plant against stress or disease, it was hard to tell a 600-year-old tree from a 20-year-old tree,” reported Dr. Richard Dixon of the University of North Texas, part of the team that looked into the ginkgo’s amazing longevity.
And this longevity has served the ginkgo well. The species has been on this planet for over 200 million years, having co-existed with dinosaurs and, indeed, outlived them. Charles Darwin himself called ginkgos living fossils.
Not that individual ginkgos do live forever. Something eventually gets them: fire, lightning, wind, erosion, development… or being cut for logging. When a tree lives 1,000 years plus, its environment is likely to change and no longer suit it. But then it dies from external factors. If it were up to its cells alone, it would apparently live forever!
It’s likely other long-lived trees, like the bristlecone pine (Pinus longaeva, some specimens of which are nearly 5,000 years old), likewise lack programmed senescence, but more studies are needed to look into that.