The plant dinosaur

In 1994 David Noble, a New South Wales National Parks and Wildlife officer, abseiled into a gorge in the Great Dividing Range west of Sydney. He found himself in a small stand of distinctive trees, with bark like bubbling chocolate, strappy, leathery leaves and crowns emerging above the rainforest. Experts examined the specimens and recognised the plant as belonging to the family Araucariaceae, which includes the hoop, kauri, Norfolk Island and the bunya pines. Excitingly, it was close to fossil specimens of pollen and leaves dating from the Cretaceous (Plate 11.1a). The species has thus existed for possibly 150 million years, once occurring over much of Gondwana. Its discovery was equivalent to finding ‘a small living dinosaur’.

The species was named Wollemia nobilis, a nice tribute to its discoverer, and is commonly known as the Wollemi pine, from the national park where it occurs. There are about 100 trees in two groves, and molecular techniques detected no genetic diversity between individuals although seeds are produced and germinate in nature.

The future of the remnant population is precarious because fire, pest or disease introduced into its small canyon could wipe out the species with its limited genetic diversity. The best measure to protect it is keeping the exact location secret. Unauthorised visitors may already have introduced the root-rot pathogen Phytophthora cinnamomi to the population.