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4月1日 the Sahara,mammoth,saber-tooth carnivoreLast Sunday, I watched ’10,000 B.C.’ (by Roland Emmerich) which showed many a vivid scene of pre-history. The quoted here below to increase some science knowledge. J
-The Sahara, which covers nearly a third of Africa, was once a lush savanna, teeming with wildlife, fish-filled lakes, and ancient humans. Between 10,500 and around 5,500 years ago, it was a good place to live.
-Humans thrived in the Sahara, fishing, herding cattle, and making pottery and art- hallmarks of Neolithic lifestyle that supplanted hunting and gathering. When rain started to become scarce around 5,500 years ago, they migrated east to the Nile Valley. It’s no coincidence that this major climate shift coincides with the rise of the early Egyptian empires. Only when the Sahara became a desert again did the emergence of the early Egyptian civilization occur.
-Hungry prehistoric hunters, not climate change, drove elephants and wooly mammoths to extinction during the Pleistocene era.
-At least 12 kinds of elephants and mammoths used to roam the African, Eurasian, and American continents. Today, only two species of elephants are left in South Asia and sub-Saharan Africa. One theory for this dramatic demise holds that rapid climate shifts at the end of the most recent major ice age, some 10,000 years ago, altered vegetation and broke up habitats, causing the death of those unable to adapt to the new conditions. Another hypothesis blames prehistoric humans, whose improved weapons and hunting techniques allowed them to wipe out whole herds of elephants and mammoths
-With their enormous, deadly-sharp canines, saber-toothed carnivores are well known to many people as frightening and ferocious predators of the Cenozoic.
-Surprisingly, there is more than one "saber-toothed cat." The saber-tooth morphology has appeared several times during the history of the mammals. Why the enormous teeth? Certainly they were used in hunting, but opinions vary as to exactly how they were used. Some paleontologists have suggested that they were used to grab and hold onto prey. A more plausible hypothesis suggests that saber teeth were used to deliver a fatal ripping wound to the belly or throat of a prey animal. 引用通告此日志的引用通告 URL 是： http://genelu2010.spaces.live.com/blog/cns!53A1EF2153CA3B20!707.trak 引用此项的网络日志
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