July 15, 2008
Rainforest Cancer Cure One Step Closer
Dr Paul Reddell, co-founder Dr Victoria Gordon and the EcoBiotics team, have discovered a rainforest plant that produces a possible cancer-fighting molecule.
Clinical trials of a previously untreatable type of cancer in horses have produced dramatic results: "The cancers were the size of a tennis ball to begin and following the injection of this drug have shrunk, died and then fallen out. Finally the skin around the tumour area has healed."
As originally reported in the Cairns Post, Dr. Reddell said, "We are now looking to move the drug to testing against obstructive tumours and skin cancers in humans."
Bio-discovery is emerging as an increasingly important and value-added attribute of bio-diversity, with important economic implications for conservation. In 2004, following the Commonwealth Government's ratification of the ‘Convention on Biological Diversity’, the Queensland Government enacted its Bio-discovery Act, to facilitate access by biodiscovery entities to minimal quantities of native biological resources on or in State land or Queensland waters, to encourage the development, in the State, of value added biodiscovery and to ensure the State, for the benefit of all persons in the State, obtains a fair and equitable share in the benefits of biodiscovery..
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June 06, 2008
The World’s Most Painful Plant
Australians might be surprised to hear that many visiting travellers perceive the country as dangerous … a landscape teeming with deadly snakes and spiders and surrounded by crocodiles, sharks and jellyfish, but what of its floral dangers?
Gympie Gympie (Dendrocnide moroides) is arguably the world’s most painful plant. Covered with hypodermic hairs on its leaves and stems, it can inject poison that causes extreme pain.
It grows most virulently in damaged rainforest along Australia’s north-east coast. Its seeds remain dormant in the soil beneath a dark understory, until germinated by exposure to intensified sunlight, such as when a rainforest tree collapses. It is found most frequently as a single-stemmed plant, 1-2 metres high. Its large, long-stalked, alternate leaves are broadly heart-shaped (∼30 x 22 cm) with serrated margins. The central vein stops short of the periphery, terminating with the stalk attachment, on the underside of the leaf. Its mulberry-like, bright pink to purple fruits are borne upon axillary stalks on female plants.
Contact with human skin can cause extreme pain, starting as a rapidly intensifying burning sensation. The pain may persist for days, but upon exposure to cold air, water or when rubbed, the pain can be reinvigorated for up to two months or more, beyond the original sting.
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May 19, 2008
Hairy Red Pittosporum
For the sake of appearance, colour can make a world of difference. In tropical rainforests, a bright upper canopy, rich in blue and UV, and a dark understorey, rich in green and orange, contrasts two distinct light environments.
When discretion is important, bright greens blend better in the upper canopy, whereas dark browns have the advantage in the understorey.
When advertising an invitation to treat, as it were, bright blues glow advantageously in the upper canopy, whilst yellow and red signals optimise conspicuousness in understorey. The Hairy Red Pittosporum P. rubiginosum ssp. Wingii, of Australia’s tropical rainforests, is an excellent example of the latter.
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May 03, 2008
Truth in Tree Rings - A Note from Gavin
How old was our eucalypt when it died in 2008?
Although frequently promoting trees as evidence of current climate change, it’s been my view for a while that the science of “dating” any specimen’s history via its growth rings, must account for extended droughts and abrupt climate disturbances such as flash flooding.
This example from yesterday’s street saga is no exception given the ACT region’s recent rainfall patterns.
I reckon our study in harsh climates also depends on the performance of particular roots over time.
Gavin.
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February 06, 2008
The Spectacular Scarlet Bean
Plants that flower and fruit from their main stems or woody trunks rather than from new growth and shoots, are described as cauliflorous or cormiflorous; those that flower from the branches are ramiflorous. The Scarlet Bean (Archidendron ramiflorum ssp. Cooper Creek) is a spectacular example of both which is currently in bloom.
The buds appear in clusters about the trunk and branches and open to reveal a stunning cascade of white filaments up to 75 mm long. The flowering is very short-lived, lasting only one day. About eight months later, glabrous fruit develops into a coil, from 80 to 250 mm long, in a discrete shade of green, until turning dramatically red as a prelude to opening. The bright yellow-orange inner tissue reveals distinctive black seeds as an invitation to a diversity of feathered distributors.
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November 08, 2007
Ferals go Crazy on Australian Sub-Antarctic Island: Who Cares? A Note from Luke Walker
Rabbits and rats are posing a severe threat to World Heritage values on Macquarie Island, as research reveals widespread damage to terrestrial ecosystems. This includes destruction of vegetation (habitat for threatened albatross species and other seabirds), and catastrophic erosion.
Erosion and heavy spring rains have caused a large landslip on Macquarie Island, in the Southern Ocean about 1500 kilometres south-east of Tasmania, killing penguins in an important colony.
Rabbits blamed for penguin deaths in landslide
The finer details of introducing dogs to rid a sub Antarctic island of rodents are still be worked through.
Macquarie Island dog plan still in the works
Turnbull to the rescue:
MEDIA RELEASE
The Hon Malcolm Turnbull MP
Minister for the Environment and Water Resources
T76 /07
4 June 2007
AGREEMENT TO ERADICATE RABBITS ON MACQUARIE ISLAND
The Australian and Tasmanian Governments have today reached an agreement to jointly fund the eradication of rodent pests on Macquarie Island to protect its World Heritage values.
The seabird populations and vegetation of the Island are under serious threat from plagues of rabbits, rats and mice.
Following from discussions between our Governments, I am please to announce that we have agreed in principle to provide funding of $24.6 million in equal shares to implement the Plan for the Eradication of Rabbits and Rodents on Subantarctic Macquarie Island.
The Prime Minister has today written to the Premier Lennon confirming the agreement under which the Australian and Tasmanian Governments will provide $12.3 million each to implement the eradication plan.
As Macquarie Island is part of Tasmania, the plan will be implemented by the Tasmanian Government, which will also meet any costs in excess of $24.6 million agreed funding.
The Australian Government funding is conditional on the eradication being managed by a joint Government steering committee supported by a scientific advisory committee.
As it takes two years for the for specialised training of dogs to hunt rabbits without impacting on the wildlife, our Governments have agreed that Tasmania will let contracts for this training and commence all other long-lead work immediately.
The Australian Government provided funding for the development of the eradication plan and in addition will continue to provide $1.6 million per year to support Tasmanian rangers who manage the nature reserve.
Macquarie Island was inscribed on the World Heritage List in 1997 on the basis of its outstanding natural universal values:
• as an outstanding example representing major stages of the earth's evolutionary history, including the record of life, significant on-going geological processes in the development of landforms, or significant geomorphic or physiographic features; and
• containing superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance.
Macquarie Island is situated about 1500 km south-south-east of Tasmania, about half way between Tasmania and Antarctica at around 55 degrees south. The main island is approximately 34 km long and 5.5 km wide at its broadest point.
Media contact: (02) 6277 7640 – Minister’s office.
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October 06, 2007
Cycad Relations Run Hot and Cold
Cycads have an evolutionary history dating back to the dry, cool age of the Triassic, when much of the world's terrestrial landscape was inhospitable to spore-producing plants. They have carried the evolutionary breakthrough of the seed from an ancient group of now-extinct plants called Bennettitaleans, to the present.
Cycads are pollinated mainly by weevils and thrips, which carry out much of their life cycle within the tissues of the male and female cones. In what could be considered an insightful adaptation to global warming (albeit at a micro-level), an ABC Science Online article by Stephen Pincock reveals how another species of cycad Macrozamia lucida uses a stockpile of sugars, starch and fats to heat their cones to around 12 degrees Celsius above air temperature to encourage thrips to evacuate to the more appealing climes of the female cones.
Whilst cycads are pollinated by weevils and thrips, the distribution of their seeds is reliant upon another group of animal carriers.
The world's tallest cycad Lepidozamia hopeii can reach twenty-metres. Every five-years-or-so, female plants produce large cones that mature over about ten months. They then collapse and bright-red seeds adorn the forest floor at the base of the plant. Mammals carry individual seeds away from the intensity of competition and remove the delectable red aril from the seed, leaving the camouflaged core to recruit away from the competitive disinterests of the parent plant.
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