Archive for agosto 25th, 2015

Origens da Vida… de Novo:

terça-feira, agosto 25th, 2015

xxxx We Now Know For Sure How Life Did Not Begin on Earth Posted by PZ Myers on August 23, 2015 PZ MYers afirma categoricamente que a teoria de que impactos de cometas forneceram a energia para aminoacios formarem peptideos e’ nula, inviavel, ele nao acredita nela. E informa que esta teoria comecou com um paper cientifico, cujo link vai a seguir ( em PDF)

Glycine oligomerization up to triglycine by shock experiments

simulating comet impacts HARUNA SUGAHARA and KOICHI MIMURA* Department of Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601, Japan We conducted shock experiments simulating comet impacts to assess the feasibility of peptide synthesis by such a process. We used frozen mixture of the amino acid glycine, water ice, and silicate (forsterite) as the starting material and applied impact shocks ranging from 4.8 to 26.3 GPa using a vertical propellant gun under cryogenic conditions (77 K). The results show that amino acid oligomerization up to trimers can be achieved. Further, linear peptides (dipeptide and tripeptide forms), which are important materials for the further elongation of peptide chains, were obtained in yields of one or two magnitudes greater than that of cyclic peptide form (diketopiperazine). These results contrast with those by Blank et al. (2001) for shock experiments of amino acid solutions at room temperature, which showed the synthesis of a comparable amount of diketopiperazines to that of the linear peptides. Thus, the existence of cryogenic conditions at the point of impact shock may be critical for the formation of linear peptides. Our results demonstrate that comet impacts could have supplied a significant amount of linear peptides on the early Earth and other extraterrestrial bodies. ( ler todo o documento e pesquisar palavra tecnica por palavra) E entao PZ Mayers revela sua teoria preferida: ” If you want to look for answers to the origin of life, you need to look at conditions that generate a gentler flux of energy that is a better analog to metabolism. It’s about flow, not bang.” Ou seja, o inicio dependeu de um gentil, suave, fluxo de energia, e nao de colisoes, impactos, relampagos. E diz: ” The best summary of how actually abiogenesis would have occurred is Nick Lane’s The Vital Question: Energy, Evolution, and the Origins of Complex Life. You know how crimes can be solved if you use the principle of Follow the Money? Life can be understood if you try to Follow the Electrons. It makes no sense to look for life’s beginnings in cataclysmic collisions, you need to search for gradients and reactions with energies that wouldn’t disintegrate cells.” Vamos entao ver este link:

The Vital Question: Energy, Evolution, and the Origins of Complex Life

Kindle Edition : U$ 12,00 ( preciso comprar este livro) Apresentacao: To explain the mystery of how life evolved on Earth, Nick Lane explores the deep link between energy and genes. The Earth teems with life: in its oceans, forests, skies and cities. Yet there’s a black hole at the heart of biology. We do not know why complex life is the way it is, or, for that matter, how life first began. In The Vital Question, award-winning author and biochemist Nick Lane radically reframes evolutionary history, putting forward a solution to conundrums that have puzzled generations of scientists. For two and a half billion years, from the very origins of life, single-celled organisms such as bacteria evolved without changing their basic form. Then, on just one occasion in four billion years, they made the jump to complexity. All complex life, from mushrooms to man, shares puzzling features, such as sex, which are unknown in bacteria. How and why did this radical transformation happen? The answer, Lane argues, lies in energy: all life on Earth lives off a voltage with the strength of a lightning bolt. Building on the pillars of evolutionary theory, Lane’s hypothesis draws on cutting-edge research into the link between energy and cell biology, in order to deliver a compelling account of evolution from the very origins of life to the emergence of multicellular organisms, while offering deep insights into our own lives and deaths. Both rigorous and enchanting, The Vital Question provides a solution to life’s vital question: why are we as we are, and indeed, why are we here at all? xxxx Apos recomendar o livro acima, PZ Myers sugere outra alternative, baseada na redox chemistry, ( Or you could try reading a paper by the always-entertaining William Martin, if you’re in more of a hurry.), e sugere o seguinte paper:

Early evolution without a tree of life (Epa! Estou abrindo um artigo separado para este paper, porque isso e forte evidencia favoravel a minha teoria) O qual vou ler agora antes de continuar isto….


Outras teorias buscam as origens da Vida numa soupa no fundo dos oceanos, na boca de vulcoes, nas costas de cometas, quando a minha teoria ja encontrou o lugar a muito tempo: na cama. E por acaso a foto desta bela mulher deixa alguma duvida?

Estou agora lendo eletron e depois energia solar.