Design & Nature Reimagined: Immortal Ginkgo?
I recently learned about the conference Beyond Tellerand and one day I want to speak there! As I was looking through past speakers, Yasaman Sheri's work and talk piqued my interest. So I went to her site and saw that she once worked for a company called Ginkgo Bioworks, which does some pretty cool bio engineering work. I was telling my husband Jason how clever the name was, because ginkgo biloba trees are both a mystery and a marvel since the species is over 400 million years old and existed before the dinosaurs. It's often referred to as a "living fossil".
And then I fell down the rabbit hole.
Immortality for trees?
The oldest known Ginkgo Biloba tree is around 3500 - 4000 years old and in China. While this in itself is fascinating, scientists don't actually know how long these trees could theoretically live. In a study done by Richard Dixon of the University of North Texas, when they studied 20, 200, and 600 year old trees, they saw no programmed cell death and no reduction of immunity between the varying ages of trees. Dixon said, "...it was hard to tell a 600-year-old tree from a 20-year-old tree."
While these trees do die, it seems that environmental or physical damage kills them first. They're not really dying of old age.
Born to die
In humans, programmed cell death, is integral to an organism's ability to live. A protein in the cells triggers the cell to commit suicide and then it's expelled from the body. Cell death means that we don't develop cancer. When cells don't follow their programmed cell death, they mutate and turn into cancerous cells. Conversely, if our body sends the message for cells to die too early, we see the development of neurodegenerative disorders such as Parkinson's. Plants still experience programmed cell death, but in a different way than humans. For plants, programmed cell death helps them adapt to environment stressors or injury. As an example, if a fungus attacks a plant, programmed cell death will occur in that area, essentially cauterizing the area to prevent further damage.
And this is what makes ginkgo trees so curious and fascinating. At least in ginkgo biloba trees up to 600 years, they didn't find evidence of programmed cell death, so what about them functions differently?
The immune system in a tree is also different than that of a human. A human has many different cells that work together to identify invading cells, attack, and expel them. It then keeps a record of these dangerous cells so it can fight it off later if it comes back. This is one reason some viruses are so hard on our bodies: our cells can't remember them and so they can cause a lot of damage before the immune system can kick in. A tree uses compartmentalization of decay. Trees can quickly grow new cells, but they can't repair damage. So they compartmentalize it in their trunk as a way to sequester the damage.
Immortality for all?
So this brings us back to the work that Ginkgo Bioworks is doing. They're working to understand cell programming. If we can better understand the cells of the Ginkgo Biloba tree, maybe we can reduce cell damage and death while also keeping the cells from mutating and harming us. Basically, immortality. That brings up its own host of ethical dilemmas and moral questions, but I doubt we'll see this come up in our lifetimes. Outside of fantasies of immortality, I think studies like this help us put the world in perspective. As humans, we look at the world through our limited view. But we are a such a tiny blip on the evolutionary scale. These trees were here before dinosaurs existed, and will likely be here long after we're gone.