Members may be interested in this article which appeared in the "ANU Reporter" Vol.26 No.4, Wednesday 15 March 1995, p.1. This is the newspaper of the Australian National University in Canberra. [my new email after today: Geoff_H_Dean@notes.north.com.au ] article begins ========== "Ancient pine shown to be from the age of dinosaurs", by Marita Black An ancient pine tree discovered in Sydney's "back yard" and hailed as one of the botanical finds of the century has been confirmed by ANU researchers and colleagues to belong to a new genus of plants previously known only as fossils from the dinosaur era. The grove of around 40 pine trees was found last year by an officer from the National Parks and Wildlife Service at the bottom of a deep gorge, in the Wollemi National Park of the Blue Mountains. The tree, informally named "Wollemi Pine", was identified as belonging to the Araucariaceae family whose members also include the New Zealand Kauri, New Norfolk Pine and the Queensland Hoop Pine. However the new tree failed to fit into either of the living two genera of the family, so the search began for possible relatives from the fossil record. Dr Mike Macphail of the newly formed Division of Archaeology and Natural History in the ANU's Research School of Pacific and Asian Studies (RSPAS), was enlisted to examine pollen from the Wollemi Pine with the aim of identifying and comparing it with other fossil pollen types. Other experts at the Australian Geological Survey Organisation (AGSO) and the Royal Botanic Gardens in Sydney were studying other aspects of the tree, such as the leaves and cones. Before pollen from the Wollemi Pine became available, the closest match to the species in the fossil record were leaves of a conifer called Araucariodies, preserved in 50-65 million year old sediments in New Zealand and Tasmania. Dr Mcphail found the pollen to be a match to a fossil pollen type first described in Victoria in the early 1960s and now known to have occurred up to 90 million years ago. This means that the Wollemi Pine would have been part of the landscape when dinosaurs roamed. Fossil pollen and spores are often used to provide a history for living plants. The age and location of fossil pollens allow species to be traced over time and place, building up an evolutionary framework. Pollen is a reliable marker to look for as it produced by plants in vast amounts and survives very well over time due to the strength of its cell wall. The appearance of pollen from different plants is also very distinctive which means that precise identification is often possible. Thanks to petroleum exploration data, the Wollemi Pine has a well-established fossil history. It is thought to have been moderately common in rainforest up to around 30 million years ago, growing in Tasmania, at Bega and Bombala and around a meteor impact crater near Perth. The most recent specimens have been found in two million year old sediments in Bass Strait. It is quite remarkable that the Wollemi Pine has been able to survive 90 million years on Australian soil, through periods of major global warming and cooling. Over this time, the Australian continent has "drifted" from a position adjacent to Antarctica to its modern position next to Asia. "Why the Wollemi Pine has survived in apparently only one of many similar gorges in the Blue Mountains is a mystery," said Dr Macphail. "Long-term protection from fire and drought due to the rugged landscape and reduced competition from other plants due to infertile soils would not have been unhelpful in the recent past." Unfortunately it appears that humans now pose the greatest threat to the survival of this ancient plant. Despite attempts to protect the grove's location, unauthorised visits have taken place. ===== article ends
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