Human Flower Project

Sunday, January 13, 2008

Behold the Wollemi Pine!

With the discovery of “living fossils” in China and, now, Australia, the EarthScholars administer a gentle bump on the head. Wake up! You might have just missed a plant celebrity. Thank you, Jim and Renee.

Through One Eye
By Joan True (1940-2006)

By James H. Wandersee and Renee M. Clary
EarthScholars™ Research Group

It seems rather “common sensical” to us that when we look at something repeatedly, we observe whatever is present to be seen, and over time, it becomes increasingly familiar to us. But is that really a defensible assumption?

Shall we conduct a little test? Surely you have watched the fingers on your hands move countless times. If you are currently sitting at a table, position one of your hands forcefully flat on the table top in front of you.  Question: Which finger is the only one that cannot be easily lifted up by itself, separately, while the remaining four are kept flat?  Although most people have looked at and used their fingers every day of their lives, few people predict that it is their ring finger which has the least dexterity. Why don’t they know this? Visual cognition studies show that we often “look” without selectively paying attention to or concentrating on particular aspects of our visual field.

Thus, the verifiable but seldom chosen answer is the ring finger—for anatomical reasons that turn out be fairly complex. However, and this is important, if you were guided by a mentor to observe your fingers systematically for an extended period of time—such as in learning to type, to play a musical instrument, or to perform sleight-of-hand magic tricks—you are much more likely to answer that question quickly and correctly, based upon your visual memory of your own finger movement. Thus, observation is really “systematized looking” that we consciously wish to make available to us for future recall—this happens whenever we are looking with a vested interest or a purpose in mind, or whenever we are looking carefully in order to try to understand something.

Another example: How many times have you looked at a US penny? Thousands of times! You get pennies in change and you count them; you lay out your pennies to pay a restaurant bill exactly; you place your pennies in a coin dish for later use. You don’t do these things with your eyes closed, do you? Questions: Does the president’s head on a penny face right or left? Which US president is it? How many times and where does his image appear on a single penny? On which side and at which clock-hour position does the word liberty appear? Is it written as LIBERTY or Liberty? It’s not easy to recall these details, is it?—unless you are seasoned numismatist (coin collector). If so, you are used to observing these features and using them as indicators to establish the grade or condition of each penny in your collection. Similar limitations apply to the untrained eye’s observations of plants, but to an even greater degree—because most people look at individual plants quite infrequently.

In our January 10th, 2006 Human Flower Project article entitled “On Seeing Flowers: Are You Missing Anything?” we explained the basic principles of our plant blindness theory which asserts that, especially in urban settings within developed countries, people tend subconsciously to overlook, undervalue, and fail to differentiate the plants in their environment—consciously sensing only a “green blur” or a verdant backdrop of vegetation against which human and animal activities of interest to them take place.

It should be noted that the United States is an urbanized nation, with 80% of its population residing in cities and suburbs. Thus, it seems likely that, unless they have been influenced by a plant mentor or are self-taught plant aficionados, plant blindness is the default botanical- attention state for most US citizens today.

People pay more attention to large plants than small plants. The largest plants in the Plant Kingdom are trees (which, studies have shown, young children don’t even consider to be plants). Trees comprise about 25% of all plant species and are the defining life forms of many large terrestrial biomes—including the temperate coniferous forest biome, deciduous forest biome, and tropical rainforest biome. You would think that by the present day, humankind would have discovered all the large species of trees on Earth—and you would be wrong. How could even experienced plant explorers overlook some strange-looking, tall trees, you may ask?

The discovery site of the Wollemi Pine
Image: Bradshaw Foundation

Consider this. In 1994, approximately two dozen 100-foot-tall trees from the age of dinosaurs (90 million years old) were discovered growing in the sandstone gorges of a wilderness area only 125 miles northwest of the most populous city in all of Australia—Sydney, the home of over 4 million people.

These trees were discovered in Wollemi (WALL-um-eye) National Park of New South Wales by David Noble, a bushwalker/rock climber/park and wildlife officer. Having previously made hundreds of expeditions exploring the park, Noble was an experienced plant observer who suddenly realized he had never seen such trees before. He stashed several twig specimens in his backpack to show to expert dendrologists (tree biologists) and plant taxonomists.  The trees that caught Noble’s attention turned out to be an entirely new tree species, and even a new genus of tree, apparently related to the ancient Araucariaceae (ah-rou-carry-ACE-eh-ee) family of evergreen coniferous trees, a family dating back 200 million years. Other members of this family include the Norfolk Island Pine (Araucaria heterophylla) and the Monkey-Puzzle tree (Araucaria araucana).

In 1998, these newly discovered living trees were officially named the Wollemi Pine (Wollemia nobilis), with the species epithet nobilis honoring its discoverer, David Noble. Part of its common name, Pine, is (as with the Norfolk Island Pine) a misnomer, because this tree merely resembles a pine (true pines are members of the genus Pinus and are typically found only in the Northern Hemisphere).

Wollemi Pine: Fossilized leaves and living leaves, in two or four flattened ranks
Photos: Paula Offutt

Later, paleobotanists discovered that existing specimens of fossil pollen and fossil seed cones (including some recovered during Australian dinosaur excavations) matched those of the living Wollemi Pines. There is now quite a well-established fossil record of this species. Journalists often call such a plant species a living fossil: an informal term for any living species (or clade) of organism that appears to be the same as a species otherwise only known from the Earth’s fossil record and that has no close living relatives.

In paleobotany, a Lazarus taxon (plural, taxa) is a classification category that disappears from one or more periods of the fossil record, only to appear again later. (The term refers to the biblical story of Lazarus, whom Jesus miraculously raises from the dead.) Lazarus taxa are observational artifacts that can occur due to incomplete sampling or local extinction in areas later resupplied. In the case of Wollemia nobilis, some existing fossil pollen and seed cones were shown to have been previously misidentified, and thus some gaps in its fossil record have now been eliminated.

Artist’s rendering of a Wollemi Pine
Image: Edge Cinema

Later scientific studies have shown that Wollemi Pines
(a) total about 100 mature naturally-occurring, living specimens, divided into three small populations within the park;
(b) populations reproduce sexually but show virtually no genetic variation—these trees are all clones;
(c) are susceptible to attack by foreign pathogens carried by visitors (hence researcher access has been carefully controlled via quarantine at the three secret natural sites within the park and $133,000 fines are posted for disturbing these trees);
(d) are strangely capable of shedding entire branches rather than just individual leaves;
(e) are host to a fungus which produces taxol, an important anticancer drug;
(f) can be raised from seed, plus be successfully propagated quite rapidly using modern tissue culture techniques;
(g) are found in three similar ecological niches featuring permanently moist, active-stream gorges, with similar soils and light regimes; and
(h) often have multiple stems originating at the base of their trunk—as many as 160.

The Australian government has helped the Wollemi Pine become a plant celebrity. Potted specimens were sent on tour to the nation’s botanic gardens. Sydney’s botanic garden organized a cooperative venture between the government and the private business sector to use tissue culture techniques to propagate and sell the tree on a commercial scale, with an international marketing plan.  Royalties from its plant sales will support conservation of the Wollemi Pine. Thus, North Americans can now order their own “living fossil” Wollemi Pine tree (check here) for a cost of less than $150. It can be cultivated as a tall tree, patio plant, or potted plant. Because this ancient and initially rare tree has attractive, unusually dark green foliage and bubbly (coco-puff-like) bark, sprouts multiple trunks, and is shade-tolerant, it is quite likely to become popular worldwide, both as a plant celebrity and geobiological teaching tool to heighten public understanding of plant evolution, biodiversity, extinction, refugia, and geologic time.

Plant zoo? Rare Wollemi Pine exhibited inside a cage for its own protection
Photo: Biotechnology Online

In 1948, the announced rediscovery of the Dawn Redwood tree (Metasequoia glyptostroboides) in China near Modaoxi by Zhan Wang (1943)—a tree previously known only by its fossils—rocked the botanical world. It is the only living species in the ancient redwood genus named Metasequoia. An easy tree to grow from seed in temperate climates, it can reach a height of 135 feet or more within a century after planting. Or, if you have no room in your yard for such a tall tree, you can grow one as a miniature bonsai tree.

As if to anticipate the focus of this article, it should be noted that Wollemi is an aboriginal word meaning “Watch out!” or, “Look around you!”

Our message is that paying attention to plants necessarily involves comparison and attending to details. We often look without seeing, without knowing what to look for, and thus we miss much more visual information than we should. Two other hikers accompanied David Noble on the day of his great discovery, but only David noticed the huge Wollemi Pines. The emotional, intellectual, and participatory rewards of careful plant observation can help give our lives and the lives of others meaning and purpose. That’s what David Noble’s and Zhan Wang’s discoveries teach us. As for the Wollemi Pine, Sir David Attenborough spoke for the embedded biological explorer that resides within each of us when he exclaimed: “How marvelous and exciting that we should have discovered this rare survivor from such an ancient past.” A plant celebrity? Indeed!