My yard is full of English ivy. Let’s suppose (which is probably not far from the case) that all this ivy came from one original cutting. Ivy spreads and the vines root themselves, so even if a vine is severed, the shoot just goes right on growing as a new plant. So in this scenario, all the ivy in my yard is genetically identical, right? And so far as I can tell, it’ll never die. I mean, of course you could kill it artificially, or some natural cataclysm could get it, but barring that, it will stay here forever, genetically unaltered forever, right?
Even better: you find there is something unique about your ivy, you patent it and sell the rights to a plant breeder. Soon, there are homeowners all over the world planting your ivy, which will never die unless it begins swallowing entire houses and the military has to be called in.
Actually, that article says a mutation occurred on one branch, which is kind of a surprise to me. That suggests that maybe all the ivy is *not *necessarily genetically identical… no?
More or less, yes. One clone of Quaking Aspen known as Pando is estimated to be about 80,000 years old. (Some say more than one million years old.) Provided the environment remains suitable for its continued survival, it will live indefinitely.
However, even clones will not remain “genetically unaltered.” Mutations will take place in separate parts of the clone and they will eventually diverge.
I grow African violets from cuttings of my existing African violets.
Every so often, one flower, leaf, or stem of an existing violet will be different than the rest of the plant.
If you clip the oddball part, and root it (you can do this with A.Violets even from a flower stem, if you add rooting powder), the new plant will sometimes come out different from its clone-parent. It may have different shaped leaves, different type of stem, different color of flower, different shape of petal or number of petals per flower, on and on. After a few generations of this, you couldn’t tell that one was a multi-gen clone of the other.
I don’t know if most plants are like this, but A.Violets are very prone to spot mutations.
To address the OP:
I think immortal may be a bad choice of words for reproduction that occurs from splitting. Individual components do grow and die, but there is still a continuity that defies anything we have language for. If you want to call these plants immortal, then you’d also have to call bacteria immortal. Technically not wrong… but not exactly the same either.
It actually isn’t so different from other animals. You have mutated genes all over your body. We usually don’t worry about these because you only reproduce with specific cells (so the change is never passed down), and most mutations are not such a big deal (for example, most cells are expressing only a few of their genes to begin with). Of course, some mutations are a big deal - some result in cancer.
So the major difference is just the fact that plants can divide and regenerate. If cutting off your finger resulted in growing a new you, then we’d notice the same kinds of things in animals.
And there’s the world famous Humongous fungus – Claimed in this article to be the oldest living thing at 1500 to 10000 years (nowhere near the 80000 year old Quaking Aspen that Colibri mentions). Still, it just goes on and on.
I love the stuff that plants do - I had a yard with pansies and violas in it, and of course I got a plant sprouting that was halfway between violas and pansies one spring!
One thing perennials do that kind of irritates me is that they don’t always hold true to what they were bred for. For example, you get a lovely peach flower, and a couple of seasons later, the flower is more pink than peach. My cerise yarrow is doing this - the plant is more white than cerise when it blooms. I’ve heard that cutting the undesirable blooms off will help keep the plant true to its breeding, but that doesn’t seem like a solution to me.
It should be noted that some perennials are far more immortal than others (depending on climate and soil).
Many have found that the only way to eliminate Yucca glauca is with a portable thermonuclear device. Mexican primrose, creeping jenny, kudzu and yes, English ivy fall into the same category. I intentionally planted variegated Artemisia (“Limelight”) and it should survive all my descendants.
However, the aspen I mentioned is actually just one organism, since it’s connected through the root system. Individual ivy plants mentioned in the OP can also continue to live indefinitely without dividing into new individuals, so it’s rather different from the situation in bacteria.