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Cassandra Pierce [The Aquans Diamonds in the Sand [Siren Lov
Brenda Novak [Hired Guns 01] White Heat (epub)
Diamond In The Rough Hidden G India Lee
Bethany Kris [Russian Guns 03 The Score (epub)
Brenda Cothern Guns & Hoses Guns
Collapse How Societies Choose t Jared M. Diamond
Dios hizo el mundo en 7 dias . Luis Piedrahita
Beau Schemery Verses of Vrele The Unlikely Hero
Big City Girl Charles Williams
Czarodziejka z Florencji Salman Rushdie (2)

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.Anyone who has experienced firsthand the overwhelming power of the life-sized painted bulls and horses in the Lascaux Cave of southwestern France will understand at once that their creators must have been as modern in their minds as they were in their skeletons.Obviously, some momentous change took place in our ancestors’ capabilities between about 100,000 and 50,000 years ago.That Great Leap Forward poses two major unresolved questions, regarding its triggering cause and its geographic location.As for its cause, I argued in my book The Third Chimpanzee for the perfection of the voice box and hence for the anatomical basis of modern language, on which the exercise of human creativity is so dependent.Others have suggested instead that a change in brain organization around that time, without a change in brain size, made modern language possible.As for the site of the Great Leap Forward, did it take place primarily in one geographic area, in one group of humans, who were thereby enabled to expand and replace the former human populations of other parts of the world? Or did it occur in parallel in different regions, in each of which the human populations living there today would be descendants of the populations living there before the leap? The rather modern-looking human skulls from Africa around 100,000 years ago have been taken to support the former view, with the leap occurring specifically in Africa.Molecular studies (of so-called mitochondrial DNA) were initially also interpreted in terms of an African origin of modern humans, though the meaning of those molecular findings is currently in doubt.On the other hand, skulls of humans living in China and Indonesia hundreds of thousands of years ago are considered by some physical anthropologists to exhibit features still found in modern Chinese and in Aboriginal Australians, respectively.If true, that finding would suggest parallel evolution and multiregional origins of modern humans, rather than origins in a single Garden of Eden.The issue remains unresolved.The evidence for a localized origin of modern humans, followed by their spread and then their replacement of other types of humans elsewhere, seems strongest for Europe.Some 40,000 years ago, into Europe came the Cro-Magnons, with their modern skeletons, superior weapons, and other advanced cultural traits.Within a few thousand years there were no more Neanderthals, who had been evolving as the sole occupants of Europe for hundreds of thousands of years.That sequence strongly suggests that the modern Cro-Magnons somehow used their far superior technology, and their language skills or brains, to infect, kill, or displace the Neanderthals, leaving behind little or no evidence of hybridization between Neanderthals and Cro-Magnons.THE GREAT LEAP Forward coincides with the first proven major extension of human geographic range since our ancestors’ colonization of Eurasia.That extension consisted of the occupation of Australia and New Guinea, joined at that time into a single continent.Many radiocarbon-dated sites attest to human presence in Australia / New Guinea between 40,000 and 30,000 years ago (plus the inevitable somewhat older claims of contested validity).Within a short time of that initial peopling, humans had expanded over the whole continent and adapted to its diverse habitats, from the tropical rain forests and high mountains of New Guinea to the dry interior and wet southeastern corner of Australia.During the Ice Ages, so much of the oceans’ water was locked up in glaciers that worldwide sea levels dropped hundreds of feet below their present stand.As a result, what are now the shallow seas between Asia and the Indonesian islands of Sumatra, Borneo, Java, and Bali became dry land.(So did other shallow straits, such as the Bering Strait and the English Channel.) The edge of the Southeast Asian mainland then lay 700 miles east of its present location.Nevertheless, central Indonesian islands between Bali and Australia remained surrounded and separated by deepwater channels.To reach Australia / New Guinea from the Asian mainland at that time still required crossing a minimum of eight channels, the broadest of which was at least 50 miles wide.Most of those channels divided islands visible from each other, but Australia itself was always invisible from even the nearest Indonesian islands, Timor and Tanimbar.Thus, the occupation of Australia / New Guinea is momentous in that it demanded watercraft and provides by far the earliest evidence of their use in history.Not until about 30,000 years later (13,000 years ago) is there strong evidence of watercraft anywhere else in the world, from the Mediterranean.Initially, archaeologists considered the possibility that the colonization of Australia / New Guinea was achieved accidentally by just a few people swept to sea while fishing on a raft near an Indonesian island.In an extreme scenario the first settlers are pictured as having consisted of a single pregnant young woman carrying a male fetus.But believers in the fluke-colonization theory have been surprised by recent discoveries that still other islands, lying to the east of New Guinea, were colonized soon after New Guinea itself, by around 35,000 years ago.Those islands were New Britain and New Ireland, in the Bismarck Archipelago, and Buka, in the Solomon Archipelago.Buka lies out of sight of the closest island to the west and could have been reached only by crossing a water gap of about 100 miles.Thus, early Australians and New Guineans were probably capable of intentionally traveling over water to visible islands, and were using watercraft sufficiently often that the colonization of even invisible distant islands was repeatedly achieved unintentionally.The settlement of Australia / New Guinea was perhaps associated with still another big first, besides humans’ first use of watercraft and first range extension since reaching Eurasia: the first mass extermination of large animal species by humans.Today, we regard Africa as the continent of big mammals.Modern Eurasia also has many species of big mammals (though not in the manifest abundance of Africa’s Serengeti Plains), such as Asia’s rhinos and elephants and tigers, and Europe’s moose and bears and (until classical times) lions.Australia / New Guinea today has no equally large mammals, in fact no mammal larger than 100-pound kangaroos.But Australia / New Guinea formerly had its own suite of diverse big mammals, including giant kangaroos, rhinolike marsupials called diprotodonts and reaching the size of a cow, and a marsupial “leopard.” It also formerly had a 400-pound ostrichlike flightless bird, plus some impressively big reptiles, including a one-ton lizard, a giant python, and land-dwelling crocodiles.All of those Australian / New Guinean giants (the so-called megafauna) disappeared after the arrival of humans.While there has been controversy about the exact timing of their demise, several Australian archaeological sites, with dates extending over tens of thousands of years, and with prodigiously abundant deposits of animal bones, have been carefully excavated and found to contain not a trace of the now extinct giants over the last 35,000 years.Hence the megafauna probably became extinct soon after humans reached Australia.The near-simultaneous disappearance of so many large species raises an obvious question: what caused it? An obvious possible answer is that they were killed off or else eliminated indirectly by the first arriving humans.Recall that Australian / New Guinean animals had evolved for millions of years in the absence of human hunters [ Pobierz całość w formacie PDF ]