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Does the Loneliest Plant in the World Need Help?

One day in 1895, while walking through the Ngoye Forest in Zululand, southern Africa, a botanist with the oh-so-suitable name of John Medley Wood caught sight of a tree. It sat on a steep slope at the edge of the woods and looked quite unlike its neighbors, with a fattish trunk (actually it had two trunks) and what seemed like a splash of palm fronds on top.

It’s now called E. woodii, in Wood’s honor. It is a cycad. Cycads are a very old order of tree. They’ve been on the planet for roughly 280 million years, but this one is special—in a bite-your-lip kind of way. Richard Fortey, one of the world’s great biologists, calls it “Surely … the most solitary organism in the world.”

Illustration by Stocktrek Images, Inc., Alamy Stock Photo
Illustration by Stocktrek Images, Inc., Alamy Stock Photo

What Wood found may be the last surviving wild example of an ancient species of cycad, which stretches back in an unbroken line to the age of the dinosaurs. Now it’s all by itself, writes Fortey, “growing older, alone, and fated to have no successors. Nobody knows how long it will live.”

Unless there’s a twist ending. And thereby hangs a tale:

Wikimedia Commons
Wikimedia Commons

In the 1890s Wood, who made his living collecting rare plants (he directed a botanical garden in Durban), had some of this odd tree’s stems pulled up and removed and, in 1903, sent one of them to London, where it sat in a box in the Palm House at the Royal Botanical Gardens at Kew. It was a very long sit, being on display—by itself—for the entire 20th century. It’s still there.

Two hundred million years ago, cycads were everywhere. The giant continent that includes today’s Greenland and Antarctica were covered with them. Pterodactyls flew between them. Big dinosaurs munched on them. During the Jurassic period, small, stumpy, palm-looking trees made up about 20 percent of the world’s plants.

Illustration by Stocktrek Images, Inc., Alamy
Illustration by Stocktrek Images, Inc., Alamy

Somehow these E. woodii survived the catastrophe that wiped out the dinosaurs, got through five different ice ages, learned to live with bigger, newer trees—conifers and leaf bearers, followed by a profusion of fruiting and flowering plants—then got pushed into smaller, then even smaller, spaces until there were merely tens of thousands, then thousands, then hundreds, and then, for this particular species, perhaps, just this one.

The problem is that these trees cannot fertilize themselves. Some plants contain male and female parts on the same individual. Not E. woodii. It is, as the botanists say, dioecious. It needs a mate.

Photograph Courtesy of RBG Kew
Encephalartos woodii, Photograph Courtesy of Royal Botanic Gardens, Kew.

When a cycad is ready to reproduce, it grows a large colorful cone, rich with pollen or seed. It signals its readiness by radiating heat or sending out attractive odors to pollinators, who travel back and forth. Once fertilized, the seed-rich cone is ripped apart by hungry seed carriers (who’ve included, over the years, not just birds and insects, but also dinosaurs, pterosaurs, and bats—these trees have been eaten by just about everybody).

But what if you can’t find a mate? The tree in London is a male. It can make pollen. But it can’t make the seeds. That requires a female.

Researchers have wandered the Ngoye Forest and other woods in Africa, looking for an E. woodii that could pair with the one in London. They haven’t found a single other specimen. They’re still searching. Unless a female exists somewhere, E. woodii will never mate with one of its own.

But it survives. Plant geneticists have cloned it.

Photograph Courtesy of Mark W. Skinner, hosted by the USDA-NRCS PLANTS Database
Photograph Courtesy of Mark W. Skinner, hosted by the USDA-NRCS PLANTS Database

Indeed, botanic gardens across the world asked Kew for clones, or “offsets,” and now you can see genetically identical versions on display in Europe, Australia, California, South Africa. The plant is frozen genetically. It’s a living fossil, “an example of the curious but expanding process of the democratization of rarity,” says science writer Richard Mabey. It might be terminal, but if you like you can shoot a selfie in front of its exact genetic doppleganger. Or visit the original. Or maybe even buy a clone for yourself.

Cycads (there are several surviving species) are popular garden plants. Some of the rarest are bought and sold secretly. “Enormous sums of money change hands,” says the Kew Gardens website, “and because of the rarity of the species and their colourful history, offsets can sell for as much as $20,000 each.”

Left: Photograph by Julian Parker, Getty; Right: Photograph by Todd Williamson Archive, Getty
Left: Photograph by Julian Parker, Getty; Right: Photograph by Todd Williamson Archive, Getty

The problem is serious, Kew says:

It is so serious that the San Diego Police Department in southern California assigned an officer to ‘cycad beat’ to monitor these precious plants. Elsewhere in the Hollywood Hills, Brad Pitt, Oprah Winfrey, [the late] David Bowie and Kevin Costner are among the celebrities that cycad-sellers report as collectors. ”I planted a huge grove of them in Brad Pitt’s garden,” says Jay Griffith, his landscape designer. ”And Brad flipped. He kept saying, ‘I want more and more.’ To me, they are most majestic when you plant gobs of them. You expect a triceratops to come around the corner and just gobble them up.” Brad is not infringing any regulations though: his cycads are the commoner cycad species, Cycas revoluta, the so-called sago palm.

Genetically Engineered Females

There is even a move, supported by Kew, to solve E. woodii’s problem scientifically. Plant geneticists have taken pollen from our still fertile surviving male and fertilized a very close cycad cousin, E. natalensis. The hope is, by “back-crossing” the two plants, they may eventually create a very close genetic approximation of a female E. woodii and so reboot the species.

This reminds Richard Mabey of “the scientific dream that woolly mammoth hybrids may be brought back from the dark world of the extinct by inserting fragments of fossil DNA into elephant genes.”

We’re trying it with animals. Why not with plants?

Yes, why not?

To Stay or Go?

Interesting question. On the one hand, we humans have crowded the world, hemmed in, poisoned and savaged any number of plants, denying them the space to grow and thrive, so shouldn’t we, when the occasion arises, repair what we’ve done? Restore when we can?

These cycads come down to us through a long tunnel of time; they’re like a chain letter from a “magical once” (as Oliver Sacks wrote). Somehow they’ve made it down to us, and isn’t our duty to keep them going, to not break the chain?

Maybe. But on the other hand, if the only way to keep them going is to take them to a lab, add a gene here, subtract one there, and try to engineer back what once was—what have we done? Is this still a “natural’ cycad? An almost-but-not-quite female cycad would keep the line going, but whose line is it then? Its own? Ours? Whose?

There’s something not quite right with scuffling through the scrapheap of disappearing plants and animals, choosing a favorite few, and “pickling” them, as Richard Mabey says, to preserve their ancientness, when we know full well that a truly living thing must make its way on its own, must adapt, mutate, crossbreed, or die. An “almost” version of a cycad may look right, but we know deep down that the chain has been broken. This is not a real descendant. It’s our clever substitute.

So I don’t want to rescue the loneliest plant in the world. I want it to get lucky.

Drawing by Robert Krulwich
Drawing by Robert Krulwich

Which could still happen. After all, there are acres and acres of uninspected bush in South Africa. Somewhere, on the side of a hill, tucked up against a rock, hanging in a shadow, I can still imagine a shy female E. woodii. She could be out there, waiting.


I’ve written about E.woodii before, so this is, in effect, a rethink, occasioned by my reading Richard Mabey’s wonderful new book of plant essays, The Cabaret of Plants (W. W. Norton & Company, 2016). The last time I wrote about the lonely cycad in London, I was all for saving it and unapologetically mournful. Now, thanks to Mabey, I’m finding this tale richer and harder to resolve. Which is a good thing. The great British biologist Richard Fortey talks about the London E.woodii in his classic Life: An Unauthorized Biography (Vintage, 1997). Oliver Sacks describes his personal encounter with the Kew cycad in The Island of the Colorblind (Vintage, 1997).

 

18 thoughts on “Does the Loneliest Plant in the World Need Help?

  1. “Surely … the most solitary organism in the world.” Man. If this isn’t a Pixar movie in the making, I don’t know what is. And it’s named Woodii!

    1. Daryl, I’m thinking of J.R.R. Toklein and his Lord of the Rings, where the “Ents”, a group of tree spirits who live crazily long lives, lose their females, their “entwives”, who wander off to some far away place, leaving the males uncompanioned and unable to reproduce. This cycad has “Ent”-like flavors wafting off of it.

      1. Interesting article, but I wondered about the part where you say plant geneticists have cloned the plant, producing clones which you then call “offsets”. Some cycads naturally produce offsets from the base of the plant, which can be removed and grown as seperate plants. Is that what happened here?

        1. Bryan, I think you may be right. I didn’t know what an “offset” was when I wrote that line, and looking now, I see that indeed they are regenerating plant parts. So that indeed may be what happened.

  2. as an fyi there are many (perhaps most maybe even all???) cycad species than can be propagated by cuttings of the stem – I’ve done this here in Florida but only with several of the more popular ones in the Cycas genus.

  3. There weren’t a lot of Wollemi Pines either. So they made a lot of small plants and sold them off for A$50 or A$100 each. But for some reason they only did it for the Wollemi Pine, not for anything else. Why doesn’t our society do this for all these rare species?

  4. Always good to see a botanical story!
    However could I just point out a common (and frustrating) misconception? ALL living things today have lineages that stretch back unbroken to the dinosaurs (and beyond to a single common ancestor). Maybe one can say that today’s cycads *appear* to have changed very little since the dinosaurs, but that is a different point (and slightly moot as they may have changed in ways not obvious from fossil records).
    It may seem pedantic, but proper understanding of evolutionary relationships and interpretation of phylogenetic trees is critical to good science, and failure leads to erroneous conclusions and in some cases can be misused by people with undesirable agenders (eg creationists). Sadly even many biologists are prone to these misinterpretations, so the more we can do to frame these statements correctly the better!

    1. Hear Hear, Bort Edwards, well said! I am also constantly fighting the confusion of pliesiomorphy (retention of ancestral character states) with ancientness. Phyletically we are all equally ancient.

  5. There are many reasons for preserving genetic stock through back-crossing, not just sentimentality.

    If there is no other option available, and the crosses are documented properly, it preserves a good deal of the genetic stock, which gives us an understanding of the plant’s phylogeny and allows for the possibility of finding organic compounds/ or genes that may have uses in medicine, food tech etc.

    When something goes extinct, we lose a whole suite of genes with potential uses.

  6. A lovely thoughtful piece Robert.
    As a student in China, more than once i was posed a comparative scenario by Chinese friends: there’s a storm, your family, who cannot swim, are washed into a gushing river. You can maybe rescue one. Do you rescue your mother, your wife, or your daughter? (perhaps they reversed the gender roles when talking to western women, who knows?). The western you saves the daughter, as she is the future. The Chinese you, they told me, would rescue the grandmother, out of respect for her age.
    I suspect this vignette was written a hundred years ago or the like. Certainly our European attitudes to conservation have changed and are continuing to change. Today’s approach may go something like this: Given how enormous Kew’s tasks across botany (including food plants), would this effort be a waste of resources, or a sort of Trojan horse to bring in funds for the other work? Conserving to benefit humans through direct resources and services, or more fuzzy reward?

  7. Hybridization is very common among plants in the wild and it is fairly safe to assume that “Woodii” has more than a bit of mixed heritage. A cross with E. natalensis would be just fine. And, while I would love to see the American Plains rewilded and elephants in North Africa again it is undeniable human narcissism to save a charismatic species and not the habitat. “Woodii” has not been a player in his local ecosystem for quite a while. Still, hope he gets lucky too.

  8. I really enjoyed the article. The last estimate I have heard is that there are at least 500 woodii plants in cultivation that all originate from offsets removed from the original plant at Durban BG. There is now more hope for a pure woodii breeding. 10 years ago cycads were thought to be genetically male or female. Since there were 22 documented cases of sex reversals in cycads, about 10 years ago I conducted an experiment to change known male Zamia vazqueziis into females, and females into males. I could go into details on the experiment, but bottom line is that I was able to change 20% of the plants to produce cones of the opposite sex. The next year, I collected pollen from a male plant, later turned it into a female, and then pollinated it with its own pollen. I told Roy Osbourne about my experiments, and since then he has written a paper that explains scientifically why I was able to do this, and now, they call it sex expression. I know a collector with a few smaller woodiis, and he has promised that when they get to be the size they need to be, I can perform my experiment on them. So there is still hope for the future.

    1. WOW! I’ve read about animals flipping from one sex to another. Clownfish (as in “Finding Nemo”) do that all the time. But I didn’t consider the possibility that our cycad in one of its iterations, might just morph into feminine form. And you’ve found “22 documents cases of sex reversals in cycads”! 22 out of how many? Your note, Tom Broome, is the reason (or one of the reasons) I love having this column. I throw some notion out there, and back from cyberspace comes this crazy notion, which, by the way, solves SO MUCH…if the organism flips genders on its own, then mates with its female clone, yes, this is a little in-breedingly worrisome, but its descendants are not human manufactures. This species would, by my lights, live on. Thanks so much for writing in.

  9. Science currently do not know how sex is expressed in cycads. Humans have Y and X chromosomes that determine sex but cycads do not. In fact we have very little chromosome information on cycads at all.

    There are many stories of “sex reversals” in cycads but how do you prove it? Many years can go by between coning events before the “change” is noticed. It is generally accepted that stress causes the so-called sex changes but many suckers or offsets has been removed from many E. woodii plants and many have been transplanted (this is commonly associated with sex changes) but yet none has changed to produce ovulate cones in more than 100 years! Just like many cycad species vigorously reproduce vegetatively and others do not, some may be inclined to sex changes (e.g. Zamia) and others less so (e.g. Encephalartos). (Good luck Tom, you may have to experiment a while!)

    The most compelling presentation on sex changes in cycads, was done at the last Conference on Cycad Biology, Cycad 2015, when Philip Rousseau delivered a paper on a cone of Encephalartos ngoyanus (I think) which had pollen and ovulate sporophylls in a single cone!

  10. Of course a lot of plants (and some animals) naturally reproduce both by cloning and sex, like Cycads do. Strawberries, date palms, irises, cacti, Komodo Dragons, potatoes – it’s a very long list.

    The offsets of cycads are called pups. They form around the base of the trunk, just below the soil level. The old trees (“it” had two trunks) found by Mr. Wood were most probably the pups of a previous tree or trees, which were also the pup or pups of previous trees going back to when both sexes were present in that cycad grove and an ancestor grew from a seed. New pups around the base of the two trees will supplant them eventually – and the family group has probably expanded and contracted repeatedly as conditions change.

    So these trees are neither alone nor lonely – and through normal mutation in the pups, they also have the ability to continue evolving. There’s not as much variation as sexual reproduction would provide, but there is some, and they are now using humans to spread their children around the world, which is a pretty good survival strategy.

    Yes, finding a female of the species would be interesting and make for more genetic diversity – but let’s not over-anthropomorphise this Cycad.

  11. The 22 documented cases were part of an article I read in Encephalartos, the journal of the SA cycad society, almost 20 years ago. Since this was mainly a list put together by people in SA, the majority of the plants mentioned were Encephalartos plants. After that, moistly Cycas revoluta. These documented plants chef mostly after a fire, freeze, mutilation, or just being dug up and moved. Sex change in cycads happens all the time. I get emails from homeowners every year that need me to answer their questions. They know nothing about cycads but swear that their sago in their front yard used to produce a basket on top, but this year it produced a tall, thin cone, or vis versa. The same year I told Roy Osbourne about my experiments, he had an accidental event that made him twice this was something real. He was asked to put 6 Cycas panzhihuensis plants in at an airport, so he dug up some extra male plants he didn’t need for breeding and installed them. Later, they all became female.
    What happens is that when these plants get stressed in various ways, they naturally produced hormones that if present at the right time if year, the cycads can produce cones of an opposite sex. With my experiment, I took stress and energy levels in mind. Since it takes more energy to have female cones as oppsed to male cones, I grew a block of known female plants in a higher sunlight and have them my cycad fertilizer for a year, where the makes I grew in shade and fertilized them with a lower energy formula. I pulled the plants out of the pots and really disrupted them and replanted them. I then put the females in the lower energy situation and the makes in the higher energy situation, and that is how I got them to switch. Right now, I have been experimenting with three chemicals, that when combined and used in solution at once, has been reversing the sex of diecious plants. So maybe some day, I might be able to just spray a cycad several times a few months before cone production, and make it produce an opposite type cone. All I need to do is do it once and produce one cone full of seeds, and this species can start producing. I already showed the people at Durban BG how to micro propagate their woodiis from sections of stem material 15 years ago, so if they wanted to make a couple of 1000 new plants, they could do that every year if they wanted to. Neither of these propagation techniques will give this species a high genetic diversification, but we do what we can with what we have to work with.

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