The largest organism on Earth, and probably the oldest multicellular organism, is named Pando. Kind of a cutesy name for such an impressive specimen, don’t you think?
If you were to meet Pando — which you could easily do, if you paid a visit to Fishlake National Forest in Utah — it would look like a forest of Quaking Aspen trees. But if you happened to be equipped to do DNA testing on plant specimens, you would realize that all of the trees were genetically identical. That’s because they’re all part of the same tree, sharing a common root system. One tree springs from a seed, long ago, and spreads out roots; but then more trees erupt from those roots, and the process simply continues. Individual “trees” might die, but that’s like you or me losing a toenail; Pando lives on. It weighs in at over six million kilograms, and is likely more than 80,000 years old (although it might be much older).
I have nothing especially profound to say about Pando, I just think it’s cool. But when you have arrow-of-time on the brain, everything resonates. Unlike most other multicellular organisms, there’s no reason why Pando should ever die, absent dramatic external factors. As long as its environment remains hospitable, Pando could live forever. Monocellular organisms, of course, do this all the time; they split into “children” which are genetically identical (up to mutations), so it’s legitimate to say that any given bacterium has lived for many millions of years. The birth/growth/death cycle is not absolutely necessary to the existence of life — it’s just useful, if life wants to avoid the very real possibility that the environment does dramatically change for the worse. Giving birth to children with slightly different genetic makeups — and then getting out of their way, by dying — gives the species a fighting chance to adapt and survive in the face of dramatic changes around it. (Update: some termites have a different strategy.)
Meanwhile, Pando abides. Good for it.



April 8th, 2009 at 9:51 am
[...] is just about the most amazing thing I’ve read all year. It’s a post at Cosmic Variance about Pando, the largest, and almost certainly the oldest multicellular, [...]
April 8th, 2009 at 10:13 am
Utah? Pah. The largest organism is in Oregon! Or at least it is by one measure:
http://en.wikipedia.org/wiki/Largest_organism
April 8th, 2009 at 10:28 am
[...] The Earth’s Elder | Cosmic Variance | Discover Magazine 2009 April 8 tags: biology, pando by Gregory The Earth’s Elder | Cosmic Variance | Discover Magazine. [...]
April 8th, 2009 at 10:32 am
Ummm, “quivering ash”? You probably meant Quaking Aspen. Ash is Fraxinus, Aspen is Populus. They’re nothing like.
April 8th, 2009 at 10:32 am
I am not an expert, but I think that, from a gene’s-eye-view, the benefit of sexual reproduction is still a bit of a mystery. In Dawkins’s Selfish Gene book, he argues that selection takes place at the level of the gene. A gene only cares about what happens to the species up to the point that it benefits itself; but in sexual reproduction, a gene only has 50% chance of being passed on.
Why are we not all asexual and immortal?
April 8th, 2009 at 10:40 am
[...] The Earth’s Elder – Discover Magazine [...]
April 8th, 2009 at 10:46 am
Jonathan, you’re right, of course. How in the world did my brain turn “Quaking Aspen” into “Quivering Ash”? I’ll fix it.
April 8th, 2009 at 10:51 am
Here’s to linking to stuff that’s cool.
April 8th, 2009 at 11:21 am
don’t forget about this giant
http://en.wikipedia.org/wiki/Armillaria_ostoyae
probably doesn’t rival in age, but certainly contends for the biomass record
April 8th, 2009 at 12:23 pm
I don’t understand the logic on why Pando should be able to live forever. Shouldn’t it be suseptible to aging like anything else? Pando still loses genetic information over time due to mutations. Eventually it should lose too much and become unviable. Having one root system and many trees does not seem fundamentally different from one tree and many branches. Just because a branch can die while the tree lives on does not mean the tree is immortal.
April 8th, 2009 at 12:30 pm
what about creosote
April 8th, 2009 at 12:51 pm
Thanks for an interesting post!
April 8th, 2009 at 1:27 pm
(Geek alert!) They should have named it Fangorn.
April 8th, 2009 at 1:39 pm
[...] big frakking plant April 8, 2009 — Richard by dpatricklewis The Earth’s Elder: [Via Discover Magazine | RSS] The largest organism on Earth, and probably the oldest multicellular [...]
April 8th, 2009 at 2:16 pm
Make up your mind. Is an aspen or an elder?
April 8th, 2009 at 2:51 pm
meichenl: One difference is that with a single-trunked tree, the organism still has a single point of dependency, i.e. the trunk. A forest fire (or a few minutes with a chainsaw) can still take out the whole. Pando does not appear to have any single sub-part upon which everything else depends, so presumably a forest fire would have to consume nearly all tree stems in 100+ acres order for Pando to not survive. It’s still a possibility, of course, but the odds just don’t compare to that of a single-stem tree.
Mutation is ultimately a concern, but not on the kind of time scales we’re usually talking about with trees. And even then, harmful mutations are unlikely to get preserved in the long term, as natural selection works its inexorable logic on the cells of each part of the organism.
April 8th, 2009 at 5:47 pm
Could probably feed all the fireplaces in the U.S. for an evening…
April 9th, 2009 at 12:15 am
[...] Shared a link on Google Reader. The Earth’s Elder [...]
April 9th, 2009 at 12:40 am
While relatively immune to mild forest fires and such, a single disease which the particular gene makeup is susceptible to, can wipe the whole being off the face of the Earth. However, a Telomere count at various parts of the thing would be an interesting exercise.
April 9th, 2009 at 12:43 am
>> Andy, I’m not an expert too but:
I supose in long range scale sexual reproduction could be better than asexual even from the gene’s point of view. The point is that in asexual reproduction genes change faster than in sexual. But they don’t like do so;) They’d like to be remain unchanged. The sexual reproduction colud be the measure to gain higher rate of permanence.
April 9th, 2009 at 1:15 am
Impressive that it could survive the climate shift from an ice age to an interglacial.
April 9th, 2009 at 1:52 am
Andy,
It’s been hypothesized (I don’t know how much evidence is yet available) that sexual reproduction in plants and animals arose as a result of competition against parasites. Parasites, with such dramatically faster reproductive cycles, can easily out-evolve their hosts. If the next generation has the same genetic makeup as the previous, then the parasites just continue to evolve while the hosts’ immune system stays nearly the same, and the hosts die.
If, by contrast, the hosts engage in recombination, then the genetic makeup of their descendants is different, and the parasites are forced to evolve all over again to survive in the presence of their new host. This gives sexually-produced young an advantage.
April 9th, 2009 at 4:45 am
“I am not an expert, but I think that, from a gene’s-eye-view, the benefit of sexual reproduction is still a bit of a mystery. In Dawkins’s Selfish Gene book, he argues that selection takes place at the level of the gene. A gene only cares about what happens to the species up to the point that it benefits itself; but in sexual reproduction, a gene only has 50% chance of being passed on.”
While it is fine that for people who don’t work in the field, Dawkins is the first word on
evolution, he shouldn’t be the last word. Note that his “selfish gene” idea is NOT
universally accepted among researchers in the field, at least not with the enthusiasm
he has for it.
See, for example, Stephen Jay Gould’s magnum opus THE STRUCTURE OF EVOLUTIONARY
THEORY. I’m sure he has also discussed this at a less technical level in some of his
natural history essays, but I don’t have the titles offhand.
Note: Gould’s side of the story might, of course, be biased in Gould’s favour, but it is
certainly not more biased than Dawkins’s version. Gould explicitly addresses Dawkins’s
view; I don’t know if Dawkins has ever responded and addressed Gould’s view.
April 9th, 2009 at 10:28 am
Biological systems aside; the similarities of a massive root ball or fungal mycelium to the “Web” are striking and beg the question, “Is the internet alive?” It certainly is massive, growing and evolving.
April 10th, 2009 at 1:03 pm
I think saying that a bacterium is ‘millions of years old’ and we are not is making an essentialist mistake. We are, every single multicellular organism (MCO), in a very real sense, nothing more than a colony of genetically identical bacteria. If we reproduce, we never die, the germ line goes on and regenerates another MCO as an offspring, just with some admixture of genetic data from our species’ gene pool. But even after the sex, the majority of the genetic code is just like the parent. but the life itself, is as old as the age of the event when life originated. And this is true for every living cell/bacteria on the planet. So, happy 3.6 billionth birthday, everybody (give or take)!!!
See what i mean? to say that MCO are different from Unicellulars begs the question ‘how’? The distinction implied in your post seems to be sexual vs. asexual reproduction. What about lateral gene transfer then? does that break the magic line of how much genetic difference constitutes a ‘new’ organism? diploidy? single point mutation? it’s all arbitrary. we can put labels on it for convenience’s sake; but really – we are all really, really, really old.
April 10th, 2009 at 3:06 pm
Compared with this, the 5000 year old Fortingall Yew Tree in Scotland, which also clones itself by root propagation, is barely into its teens!
Following on from Thomas’s point above, I thought most of Utah was covered in glaciers during the last ice age, and the remainder covered by Lake Bonneville (whose remnant is the Salt Lake that gives its name to Salt Lake City). But evidently there must have been a few patches of vegetation here and there, including this oversized bush.
April 10th, 2009 at 3:58 pm
Has anyone actually done a DNA test on Pando or examine his (you know Pando is male, right?) roots? I’ve been told that no one has, but nothing I’ve read so far appears to answer the question either way.