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quinta-feira, 23 de dezembro de 2010

Dados matam consenso sobre a gênese africana do homem

Reinaldo José Lopes

Fonte: Folha de S. Paulo
http://www1.folha.uol.com.br/ciencia/850176-dados-matam-consenso-sobre-a-genese-africana-do-homem.shtml

Com um punhado de "papers" (artigos científicos) publicados ao longo deste ano, o sueco Svante Pääbo e seus colegas embolaram o que parecia ser um consenso dos mais consolidados no estudo da evolução humana.

E o mais irônico é que Pääbo foi um dos arquitetos desse consenso. Ao longo dos anos 1990 e 2000, parecia cada vez mais claro que as raízes do Homo sapiens eram africanas, e só africanas.

Numa grande onda de expansão que teria começado há uns 60 mil anos, teríamos deixado o continente ancestral e varrido os chamados hominídeos arcaicos -neandertais e Homo erectus entre eles- da Eurásia.

A equipe do Instituto Max Planck ajudou a consolidar essa ideia ao obter DNA mitocondrial de vários espécimes neandertais e anunciar "desculpe, nenhuma pessoa hoje tem esse tipo de mtDNA".

GENE VERSUS GENTE

Por isso mesmo, Pääbo e companhia apostavam que a mestiçagem entre Homo sapiens e primos arcaicos era impossível ou, no máximo, irrelevante. Mas sabiam, como costuma dizer o bioantropólogo brasileiro Walter Neves, que "história de um só gene não é história de população". E o mtDNA equivale, na verdade, a um único gene.

Muitas pesquisadores contrários ao consenso, por isso mesmo, sentiram-se vingados com a confirmação dos cruzamentos entre H. sapiens e neandertais. Os dados de Denisova, porém, levam a coisa para outro patamar.

Afinal, se um hominídeo raro a ponto de ainda não ter sido identificado via fósseis pode legar genes para papuanos de hoje, é sinal de que a mestiçagem entre espécies pode ter sido relativamente comum nessa época.

É provável que muita gente não goste do fim do consenso por razões que passam raspando pelo ideológico. A hipótese da origem africana tinha, de fato, a vantagem de reforçar a ideia de uma origem comum, recente, para todas as pessoas vivas hoje -uma refutação genômica do racismo, digamos.

Nossas diferenças, pelo visto, vão um pouco mais fundo. Que seja -é uma boa razão para celebrá-las e para conviver com elas.

domingo, 5 de dezembro de 2010

Religious do not have monopoly on virtue, Queen tells synod

Riazat Butt

Fonte: Guardian
http://www.guardian.co.uk/uk/2010/nov/23/queen-synod-virtue

Believers and atheists equally able to contribute to country's prosperity, says monarch

People of faith do not have a monopoly on virtue as British society was now "more diverse and secular", the Queen told the Church of England today in an address to its governing body.

Speaking at Church House, central London, she told members of General Synod that believers and atheists were equally able to contribute to the prosperity and wellbeing of the country.

The Queen, who is supreme governor of the Church of England, said: "In our more diverse and secular society, the place of religion has come to be a matter of lively discussion. It is rightly acknowledged that people of faith have no monopoly of virtue and that the wellbeing and prosperity of the nation depend on the contribution of individuals and groups of all faiths and none."

But, recalling the words of Pope Benedict XVI from his UK visit last September, she said churches "and the other great faith traditions" retained the potential to inspire "great enthusiasm, loyalty and a concern for the common good".

Around 480 clergy, laity and bishops are gathered in central London to debate and vote on issues and policies affecting the life of the church.

At times the meetings stray from the Church of England stereotype of sandal-wearing niceties, descending into acrimony and outright hostility, especially over contentious issues such as women bishops.

Around 50 traditionalist clergy and five bishops have announced their intention to convert to Roman Catholicism, following a Vatican initiative, because they are unhappy with the level of protection from female ministry offered in the draft legislation that permits the ordination of female bishops.

The Queen referred to this tension in her address, saying synod had "many issues to resolve" in order to remain "equipped for the effective pursuit of its mission and ministry", but that this difficulty might in fact revitalise the church.

"Some will no doubt involve difficult, even painful, choices. But Christian history suggests that times of growth and spiritual vigour have often coincided with periods of challenge and testing."

She made no mention of the royal wedding, which will be held at Westminster Abbey, the location of that morning's eucharist, but the subject was very much at the forefront of everyone's mind, not least because of the suspension of a Church of England bishop and synod member who made disparaging remarks about Prince William and Kate Middleton's engagement on his Facebook page.

Pete Broadbent, a suffragan in Willesden, said there ought to be a party in Calais "for all good republicans" to avoid the "nauseating tosh" surrounding the royal wedding. After criticising royalty for a history of broken marriages and a "corrupt and sexist" hereditary principle, he then went on to attack the "gutter press" for "persecuting" the royal family.

Yesterday Broadbent apologised for his remarks, calling them "deeply offensive". But it was too late and his diocesan superior, the bishop of London, asked him to withdraw from public ministry until further notice.

The public outcry – from clergy and politicians alike – over the Facebook posts may have prompted the archbishop of Canterbury to tell the Queen, to prolonged applause, that he spoke "on behalf of everyone here" in "expressing our delight" at the "family news announced last week".
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