Showing posts with label climate change. Show all posts
Showing posts with label climate change. Show all posts

Aboriginals Did Not Wipe Out Megafauna

The argument continues over whether humans were responsible for the extinction of megafauna. Giant emus, large kangaroos, marsupial lions and diprodons were destroyed by Aboriginals in Australia according to new research. This claim is based on fungi in dung of herbivores. For 130,00 years, despite dry periods, charcoal and pollen levels in dung remained the same until Aboriginals arrived. This means that climate change was not responsible for the extinction of megafauna 40,000 years ago.

There is a problem with this. When Captain Cook arrived in Australia the Aboriginal population was extremely low. Forty thousand years ago there would have been only a few hundred thousand of them. How could this low number possibly destroy all of the large animals? Some megafauna would have survived in regions where Aboriginals did not go. Australia is a very large continent.

It is claimed that when the megafauna died out the vegetation changed with more fires, and eucalyptus forests spread out killing off rainforests. Spores in dung is flimsy evidence to support a claim that human arrival led to the demise of megafauna. Rainforests being taken over by eucalyptus sounds very much like climate change. Furthermore. prevailing evidence shows no human remains among megafauna fossils.

Saying that the dung research proves humans destroyed giant animals is still not proven beyond doubt. Gavin Prideaux's announcement that the study "supported mounting evidence that climate change was not to blame" is premature.
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Paleontology

Research Program to Determine Climate Change Impact on Man's Move Out of Africa

It is known that the climate change caused by an asteroid hitting the Earth 65 million years ago led to the extinction of dinosaurs and the rise of mammals. Other extremes in climate pushed humans to move out of Africa. The National Research Council in the US has released a report calling for funding for more research into climate change and the human movement issue.

Paleoanthropologists and geologists plan the following program: find new fossil sites with remote sensing tools to determine when new species arose: drill ancient lake beds in Africa for more information on human evolution: develop regional models on how climate differed in parts of Africa over the last 100,000 years: and educate the general community on how climate change led to Man moving across the world.

A meeting is to take place on 31st March next year to discuss the determinations of the report and how such a program can be initiated. The first priority, of course, is funding. The present economic climate does not bode well in this regard. However, scientific endeavours must more forward.
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Science

Australian Spotted Jellyfish Invades Spain

Though it is not unusual for alien species to invade Australia, it is unusual for animals native to Australia to become pests in other countries. The Australian spotted jellyfish, phyllorhiza punctata, is stinging bathers on Spanish beaches.

The jellyfish is not dangerous to humans, but it causes a painful sting. Though called the Australian spotted jellyfish it is also found in North Carolina and the Gulf of Mexico.

Seven beaches were closed in Spain to protect people: Cala Cerrada, La Zenia, Cala Capitan, Punta Prima, La Mosca and Playa Flamenca. There are fears that the jellyfish will arrive on British beaches this summer. Climate change, pollution and overfishing are being blamed.
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Climate