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Contents: Introducing Australia and New Zealand Farewell to Amsterdam and Congress 2002
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Introducing Australia and New Zealand - Host Countries for |
About 150 million years ago Australia and New Zealand were
part of one supercontinent, Gondwanaland. In time, with movements of the
earth’s crust, the continental fragments that comprise New Zealand
and Australia drifted north from Antarctica. New Zealand has been separated
from other land masses for about 70 million years, and Australia for about
50 million years. This long isolation nurtured the evolution of unique
communities of fauna and flora.
Wattle – the familiar name for acacias in Australia – will grow in nearly all habitats. Over 700 endemic species may be found from the arid centre to the edges of the rainforest, and as high as subalpine heath. The present day result of all this geological activity in New Zealand (also known as the “Shaky Isles”) is the spectacular and beautiful snow-clad Southern Alps, thought to be still rising at the rate of 10mm per year, outstripping the considerable forces of erosion. The North Island has a central region of geothermal activity – geysers, steaming ground and boiling mud – as well as a “line” of volcanoes. Over 50 volcanic cones in the Auckland area are testimony to past volcanic activity.
Sheep, dotting a landscape of green fields, with a backdrop of hilly terrain, is very characteristic of New Zealand Scenery. Australia, by contrast, is far removed from the regions where earth’s crustal plates meet, and has been tectonically rather quiet for a very long time. It is the oldest and flattest of the continents, and for millions of years has been steadily eroded and worn down. Erosion of the sediments of the Great Dividing Range adjacent to the central east coast of Australia has resulted in the formation of the largest sand island in the world, Fraser Island. The latter, together with four other large islands, form huge deposits of sand off the coast of South-East Queensland. Evidence of the antiquity of this long eroded land is found in Western Australia in particular. Rocks which occur in the Murchison River area date back to 3.6 billion years, while fossil remains of some of the oldest forms of life on earth, radiometrically dated at about 3.5 billion years old, have been found in the Pilbara region. The modern derivatives of these stromatolites can be seen in several locations along the West Australian coast.
Queensland is noted for its flowering trees, both endemic species and those which occur in similar latitudes around the world. This Poinciana, flowering brilliantly in North Queensland, is a native of Madagascar. Although the arrival of Polynesians in New Zealand is shrouded
in legend, it seems that early migration from other South Pacific Islands
began about a thousand years ago. With successive migrations over the
next eight hundred years, the habitable regions of this pristine landscape
were transformed, with considerable destruction of native flora and fauna.
The big flightless moa (3 metres tall) was hunted to extinction, and fires
turned forests and fernland into scrub and tussock grassland. Introduced
dogs and rats attacked ground-dwelling birds (there were no native land
mammals apart from bats). Over the centuries the Polynesians (later called
Maoris) brought their root crops of kumara, yams and taro to their new
land. They developed agriculture-based societies, as techniques to grow
these crops in a cooler climate were devised. The first inhabitants of Australia, named Aborigines by European explorers, arrived from the south-east Asian region between 50 and 60,000 years ago. Lower sea levels of the late Pleistocene enabled these stone-age people to spread as far south as Tasmania. In harmony with a relatively harsh environment, the Aborigines adopted a hunter-gatherer lifestyle, using simple implements made from stone, shells, bone and wood. There were no outside influences to provoke change and the landscape lacked plants and animals that could be domesticated. When Europeans from the British Isles arrived in 1788 the Aborigines did not have the means to resist the steady expansion of settlement over the whole continent. At a similar time in New Zealand, following on the heels of early sealers and whalers, this country was also settled with a European style of land occupancy, by migrants mostly from the British Isles and Australia.
Lake Tekapo, adjacent to the Southern Alps in New Zealand derives its attractive turquoise colour from finely ground rock particles held in suspension in the glacial melt water. Both countries now have a very large agricultural base, with a great variety of animals and crops, especially sheep, beef and dairy cattle, pigs, grain crops, sugar, cotton and fruit – especially grapes. Forestry and fishing are also valuable to both economies. Approximately two-thirds of both countries is used for crop production and grazing; though it needs to be noted that much of the current prosperity in Australia is based on mining. Since environmental impact studies are a fairly recent phenomenon it was not realised at the time that much of the land occupancy by Europeans over the past two hundred years was unwise. Wholesale destruction of forests and woodland occurred, and animals were introduced from Europe that wreaked havoc on native fauna and vegetation. For example, the European rabbit in Australia has been a monumental pest, and only since 1995 has it been brought under reasonable control by application of the rabbit calicivirus, which causes rabbit haemorrhagic disease. In New Zealand, the brush-tailed possum was introduced, and now 70 million of them are doing enormous damage to particular trees such as the lovely scarlet-flowering rata. The stoat was brought into New Zealand to eat the “introduced” rabbits, but developed a taste for kiwi instead. Overzealous land clearing has produced much erosion and loss of valuable topsoil, and in Australia in particular, the problem of salinity in the soil (that was kept in check by the natural vegetation) is so bad there is real doubt that the problem will be solved. Both countries are now very actively trying to reverse the damage of the past two hundred years. Millions of trees have been planted in recent times and legislation ensures that care of the environment is given high priority. On the human level too, much is being done to repair relationships with the original inhabitants of both countries, but Australia languishes behind New Zealand in this regard. Australia is only two percent smaller than continental United States but has a population of only 19 million. USA has more than 260 million. This discrepancy in population levels reflects Australia’s huge semi-arid to arid interior. Along with scarcity, there is also extreme variability of rainfall. Brisbane, on the east coast, in the wet season month of January, might receive eleven inches of rain, and only one inch the following year. Blue skies and periodic drought are characteristic of much of the country, and water conservation is a major issue throughout Australia. New Zealand, lying between latitudes 34° and 47°S
is directly in the path of the so-called “Roaring Forties”,
and has a much kinder rainfall regime. Since the country is quite mountainous
throughout, and the moisture laden westerlies come off a vast stretch
of the Southern Ocean, the mountains are frequently capped with, or shrouded
in cloud. This phenomenon gave rise to the very picturesque Maori name
for New Zealand – Aotearoa – the Land of the Long White Cloud.
Roma Cooke |
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Two Famous Pathologists
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Camillo Golgi (1843 – 1926) shared the 1906 Nobel Prize for Physiology or Medicine with Santiago Ramon y Cajal (1852 – 1934).
Cajal (centre) with some of his disciples In 1873 Golgi devised the silver nitrate method of staining
nerve tissue. This stain allowed him to demonstrate nerve cells which
had many short, branching extensions (dendrites) by which they connected
with other nerve cells.
Golgi with his drawings of nerve cells.
Purkinje cells in the cerebellum stained with a silver stain showing axons, and the basketweave pattern of the dendrites which communicate between adjacent cells.
The fine structure of cells in the sympathetic nervous system of an adult human. The two smaller cells show axons and dendrites with connections between the cells. The larger cell, a neuron, shows its internal fibrillary pattern. Santiago Ramon y Cajal (1852 – 1934) shared the 1906 Nobel Prize for Physiology or Medicine with Camillo Golgi for establishing the neuron as the basic unit of the structure of the nervous system. He showed that nerve cells were separate from each other and communication occurred across their membranes. He improved Golgi’s silver nitrate stain (1903) and developed a gold stain (1913). Using these stains he was able to demonstrate the fine structure of the nervous system of human embryos and adults, and also of animals.
Camillo Golgi, Nobel Prize winner in 1906 with some of his publications and a drawing of nerve cells. His Professorial appointments were as follows: University of Valencia (1884 – 1887) ; University of Barcelona (1887 – 1892) ; University of Madrid (1892 – 1922). In 1920 King Alfonso 13th of Spain ordered the construction of the Institute Cajal in Madrid. Cajal worked there until his death in 1935. The information for this article was provided by Paolo Scarani – consultant to the Museum of Pathology “Cesare Taruffi” Unifersity of Bologna, Italy (Golgi) and Francisco Martinez Tello, Professor and Chairman of Pathology, the University Hospital, Madrid (Cajal). Francisco’s grandfather was a pupil of Cajal. The photos of Golgi were taken from displays in the Medical Museum of Pavia, with permission from the Curator. Robin
Cooke |
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Meetings |
XXIV Congress
of the Brazilian Society of Pathology 92nd USCAP
Meeting British
Division Intraeuropean-Mediterranean
Conference Third IAP
Asia Pacific Meeting Tutorial
on Neoplastic 19th European
Congress of Pathology |
The latest WHO Blue Book was launched at the Amsterdam Congress.
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More stories from this Issue on page 2 |
