June 30, 2012 | 10
In 1994, New South Wales National Parks & Wildlife Service Officer David Noble stumbled on some trees in a canyon in an inaccessible part of Wollemi National Park. He’d never seen anything like them before. Indeed, when he took samples to botanists, they confirmed it was something they’d only ever seen before in the fossil record.
For those who think there’s little left to discover on our planet, it should be noted these rare trees were discovered a mere 150 km away from Sydney, in a wilderness area in the Blue Mountains. If giant aged trees can still be discovered in this day and age in major, industrialized countries, then there is still plenty out there left to surprise us.
I stumbled onto one of these trees growing in the Mount Lofty Botanic Garden in the Adelaide Hills in South Australia, and it startled me how much the leaves resembled the ancient conifer reconstructions I’d seen at the Denver Museum of Nature and Science.
That’s because some of the earliest conifers and the members of the conifer family the Wollemi “pine” belongs to — the Araucariaceae — look very similar. Strap-like leaves, branches growing in distinct whorls, male and female cones, and waxy leaves were and are the order of the day (see here for images of an ancient conifer with a similar look. Also here for a fossil). Modern conifers in the giant Pine family (pines, spruces, firs, larches) and the cypress and yew families continued their march toward water conservation by shrinking the strappy leaves down to needles. But the Wollemi pine and some of the members or the Araucariaceae of its family still retain their ancestral, more leaf-looking leaves.
Wollemi pine was so distinct that it was placed in its own new genus, but there were two other genera in the family. Who else? Some strange and notable plants indeed. Many of them go by the completely, utterly incorrect name of “pine” because there’s no common name for their group, they live mostly in the southern hemisphere (northern members of the family went extinct at the end of the Cretaceous) and english-speaking people thus had no words for these strange trees. Instead, they used “pine” as a generic name for a conifer and appended various local descriptors: wollemi pine, Norfolk Island Pine, Kauri Pine, etc.
You may know Norfolk Island pines from their widespread use as houseplants in the Northern Hemisphere, and landscaping trees in Hawaii and the southern hemisphere. Kauri pines have produced some of the largest living trees in the world, including the mighty Tane Mahuta, “Lord of the Forest”, which I visited in northern New Zealand on my recent trip. I felt an electric shock when I realized the size of it — 43 feet in circumference and 16 feet across. When it comes to truly galactic-scale trees, no still photograph can ever convey their might, so I hesitate to show this picture, but here is me in front of the tree. I’m the small speck at the base of the tree. The tree itself is a good 30-40 feet behind me.
Here’s a closeup of a young kauri’s strappy leaves:
The Araucarians also include the notable and delightfully named “monkey puzzle tree“. Allegedly, the curious name for this spiky tree came from an observation by one proud owner that climbing that tree “would puzzle a monkey”.
You may have examined some other Araucarians in person, even if you live in America: many of the expired trees in Petrified Forest National Park in Arizona were members of this family called Araucarioxylon arizonicum that grew to 200 feet before 200 million years ago.
What all these trees have in common, besides their common ancestry, is P.O. Boxes in the southern hemisphere. They are, in fact, all members of the “Antarctic Flora“, the remnants of the plant life that thrived on the ancient supercontinent Gondwana, the southern half of the former One-Continent-to-Rule-The-All Pangaea.
When Gondwana itself broke up, India and Africa headed northward, merged with the remnants of Laurasia (the northern half of Pangaea), and lost much of their Antarctic flora. Antarctica broke away from South America, became polar, and lost most of its plant life due to the persuasive presence of a crushing, miles-thick ice sheet.
But South America, Australia, New Zealand, and parts of Southeast Asia still contain plants that were all once part of the Antarctic Flora, despite their now-extreme distance from one another. Hence, the southern beeches (Nothofagus sp.) are found in South America, Australia, and New Zealand. The monkey puzzle tree is found in South America, the Kauri in New Zealand and the Norfolk Island Pine in the Pacific north of Australia and New Zealand.
Next time, we’ll talk about a huge, gorgeous, and startlingly beautiful family of living plants that was also part of the Antarctic Flora, and which most Northern Hemisphere dwellers have never seen before in their lives.
Secrets of the Universe: Past, Present, FutureX