"A few days ago we talked about the mitochondria, and then summarize the properties of this organelle to introduce the topic of today, in the way then we will see, it is bound .
"As we looked, the mitochondrion is an organelle that can be from 1 to 4 microns (μm ) and can measure a diameter ranging from 0.2 to 1 micron, is presented with a form bean and located in the cytoplasm surrounding the nucleus of animal cells and is responsible for energy production and cellular respiration takes place, then it regulates the cycle e sviluppa calore. Tuttavia, vi avevo già detto che il tema di oggi non sarebbe stato questo, pertanto non ci interessa rivedere nei dettagli la sua funzione – la quale, dopo la scorsa lezione, sono certo voi tutti conosciate. Oggi, invece, vedremo cosa il mitocondrio ha da raccontarci.
«Partiamo dal 1987 , anno in cui i genetisti dell'Università di Berkeley Ca Allan Wilson e Mark Stoneking resero pubblici in sincronia con la dottoressa dell'Università delle Hawaii Rebecca Cann i risultati delle loro ricerche sul DNA mitocondriale. Furono analizzate 147 donne appartenenti a razze differenti ed ubicate in regioni geograficamente molto distanti tra loro, in modo da campionare the entire world population, according the assumptions of this research, each individual inherits mitochondria only from the female line and mitochondrial DNA analysis of each subject shows that all humanity today is descended from one woman (later called Mitochondrial Eve) lived about 150,000 years ago and believed that the phylogeny be placed in South Africa. As was expected, in the academic world is more or less created a clear divergence between those who denigrated the promulgation of Eve Connection and those who cheered them.
"Just a few decades, other researchers substantiate and expand this theory. In October 1999 Himla Soodyall and Trefor Jenkins, both scientists dell'Università di Johannesburg, analizzando campioni genetici prelevati dal popolo del Khoisan (il più antico gruppo autoctono sudafricano), rinvennero le tracce dell'Eva mitocondriale. Nel dicembre del 2000, invece, Ulf Gyllesten dell'Università di Uppsala irrobustì ulteriormente le precedenti tesi dell' Eve Connection dirigendo una ricerca molto accurata e pubblicata sulla rivista scientifica Nature ; fu esaminata la configurazione dell'intera sequenza di DNA mitocondriale di cinquantatré persone appartenenti a diverse etnie dei cinque continenti ed emerse che l'origine africana dell' Homo Sapiens fosse palesata da quattro linee ereditarie del DNA mitocondriale, di which would originate at the three major sub-Saharan Africa and the fourth, less important, the derivation is not African. Moreover, it was found that the mitochondrial matrilinearity was much more varied than in black population of other continents. This, if I had to deepen some aspect of the hours that I do not want to face, may explain why most people accept a social condition that can not be defined exactly "optimal." But now we are in the field of mere speculation, then we move on.
"What emerges from this? It follows that if the theory of mitochondrial were correct, the human race, between 100,000 e i 200.000 anni fa, uscì dall'Africa per occupare il resto del mondo annientò le altre specie di ominidi ed umani che ebbero la sfortuna di trovarsi sulla strada di questa nuova stirpe, incluso l'uomo di Neanderthal che, per un un certo periodo, fu erroneamente considerato antenato dell' Homo sapiens . Se questa osservazione dovesse sembrarvi eccessiva, vorrei ricordarvi come gli europei hanno annientato quasi del tutto i cosiddetti “indiani d'America” dal momento in cui hanno invaso i territori dove i nativi erano stazionati.
«Un altro aspetto della questione lo dobbiamo affrontare esaminando – o, per meglio dire, ri-esaminando – l'evoluzionismo darwiniano. È circa dal 1871 (anno in cui Darwin published The Descent of Man ) that is officially recognized our descendants (Homo sapiens sapiens ) from primeval monkeys, this is because there is always reliable, often slavishly, as Darwin said in his book. This does not mean that the founder of evolution was off course, but he was the founder, the conductor of the seminal studies that were used as a foundation, they then had to bring a more solid truth and enlightenment. However, because of some of his followers trovatisi in error, still being taught in the name of Darwin that man is descended from apes without dwelling on that because the researcher could not spread because they could not decode: the enigma of what he called "missing link", which until it was resolved was well aware that it can not be closed the investigation into the genesis of species.
"It's a problem that still has not been limited, however, some hypotheses on the evolution have been excluded by arguments quite convincing. In this respect we can mention, for example, some archaeological discoveries of equal importance to the scientific view until now. In 1857, in the Neanderthal Valley near Dusseldorf, was found the skeleton of a hominid from the position not yet built, a low forehead, the protruding jaw and stocky. Was defined nomen omen, Neanderthal man, and was the most widespread race of hominids in the Paleolithic. Following other findings in Europe, Asia and Africa the origin was placed chronologically in a time prior to 70,000 BC and it was thought that they were the result of a gradual evolutionary process resulted, since 300,000 BC, a primitive form of Homo erectus .
"Just eleven years later, in France, Cro-Magnon, were retrieved the first remains of Homo sapiens : tall, erect, with a broader skull and structured differently from that of Neanderthals, the Cro- Magnon lived in a company's most advanced and had a more pronounced intellectual spirit, as evidenced by their artistic expressions, clothes and style of life they led. Although around 35,000 BC seems that the ' Homo sapiens and Neanderthals to be crossed, in July 1997, Svante Pääbo and his team at the University of Monaco managed to extract DNA from a Neanderthal bone fragment, the analysis of which brought down the hypothesis of hybridization between species and revealed a genetic difference so important that if they had existed an ancestor common ancestor, was so far from being a marginal figure now estimated.
"The officer was evolutionary framework già stato minato sette mesi prima, quando sull'isola di Giava furono portati alla luce dei teschi vecchi di circa 40.000 anni che possedevano i connotati dell'Homo erectus che, fino a quel momento, si credeva estinto da almeno 200.000 anni.
«Eccoci, dunque, al cuore della questione: se l' Homo erectus e l'uomo di Neanderthal hanno convissuto 40.000 anni fa e il Neanderthal, a sua volta, con l' Homo sapiens 35.000 anni fa, si può desumere che ciascuno di essi non è l'evoluzione dell'altro ma, anzi, una forma separata come lo è la tigre dal lupo.
«Tra il 1911 e il 1972 in Tanzania, Kenya e Sudafrica vennero esumati i resti di antichi ominidi non compatibili con le tradizionali knowledge of evolution, thus their origin was neglected. Nevertheless, in 1974, the University of Chicago archaeologist Donald Johanson discovered in Ethiopia, for Hadar, a group of bones belonging to a first female to become famous with the name Lucy. Then were brought to light the remains of thirteen other individuals who, along with Lucy, were traced to a full 3.5 million years BC and became known as "First Family", not far from the place of discovery, some tools were identified Stone and prints dating back to the same period. The interesting part is that, given their form, the prints did not seem to belong to a hominid any: high arch of the foot, heels Rounded toes pronounced and elongated toe characterize and distinguish it from other prehistoric races in which, until then, we had encountered. How is it possible that more than 3 million years ago there had been a highly evolved species of the most recent Neanderthal remains to be verified, but, proceeding exclusion, mainly due to information disclosed by the mitochondria, we can say with some confidence that we at least spread the mistaken interpretation popularized by the followers of Darwin.
"I have enough doubts crept? Have a question? ... You. You with long hair. You're welcome. "
" Ma .. this is not the course of Modern and Contemporary History of Growling to the bitter end? "
Ideas and information were learned for the most part:
The shadow of the winged god Danilo Arona
The mysterious origins of the Grail Kings by Laurence Gardner .
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