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Single Migration Out of Africa is Wrong - Scientists

The long held "belief" that humans came out of Africa 60,000 years ago has now been officially announced as wrong by scientists. Migrations had been regularly been pushed back as far as 120,000 years before the present. It seems migration was constant not in waves. New research methods detect Homo sapiens in Asia very early, particularly in China. Genetic traces of these people are very low in modern humans. This indicates that the initial movement was slow from Africa. Later it became of a flood of Inquisitive searchers of new regions beyond. The early arrivals interbred with Denisovans and Neanderthals. These humans were taller and slender than those who came later. Neaderthals made tools from large flakes while humans technology involved lighter, finer cutting blades and spear heads. This was probably because Neanderthals were more muscular and tended to bash the quarry to death. Humans were more creative, carving antlers and bone. They made ivory flutes. C

Not Much Sleep with First-Night-Effect

SAnthropology: we have evolved to be on guard on the first night when sleeping in a new place. Man is still a hunter. We may live in cities and believe we are advanced but our genes have evolved to survive in the wild outdoors beneath the starlit night sky. If we move into a new environment getting a good night's sleep on the first night is a problem. Our brain is "on-guard" against unknown dangers. This phenomenon is in all animals. One hemisphere of the brain will sleep while the other remains on sentry duty. This "first-night-effect" is permanent. There is no cure because it isn't an illness. After the first night the brain adapts, records the new environment and deems it to be safe. Tests show that the left hemisphere sleeps lighter in a new situation. Slow-wave activity is weaker than the right hemisphere. Furthermore, the default-mode network which involves mind wandering is more active. This indicates that the brain is checking th

Little Penguin of Australia and New Zealand are Different species

Animals may look alike and are asumed for decades as being one and the same, but scientists are often wrong. Australian and New Zealand little penguins ( Eudyptula minor ) look identical, However, new reseach shows that they are different species.  The cute little penguin is the smallest of all penguins. It is only 30cm tall. It lives along the southern coast of Australia and coastal New Zealand. Many scientists find it surprising that two different species inhabit the same region and look very much alike. The answer lies in the nature of the niche. Animals evolve to take advantage of a particular niche, so to a large degree the niche shapes the animal. There is strong opinion that the Australian little penguin should be given a name. A name has been put forward: Eudyptula novaehollandiae . There is a problem as the Australia species is also found in Otago on the southernmost tip of New Zealand: how they got there is a mystery. ◆ Biology y Buchanan   ◆ Adventure Australia Fu

New Classification System for Bird Species

Birds are the most diverse creatures on Earth.  Not only have they changed into different species on large continents, they have also adapted specifically to environments on islands. A new classification system is in the form of a circle with increasing diversity as one moves out in time from the center.  different types of birds are correctly located on the figure covering a period of 50 million years. There is not one specific ancestor.  "Base" species take the form  of a circle of time moving out from the center and new kinds of birds branch off directly to the outer edge.  Fast evolving birds are in red; slower ones are drawn in blue. Significantly birds such as woodpeckers often split into new species, while hornbills, for example, did not.  There was more diversification in the Western Hemisphere.  Furthermore, species did not proliferate in the tropics because the climate remained stable there over a long period. http://www.adventure--australia.blogspot.com/ http:/