Pobre Darwin, vida multicelular há mais de 2 bilhões de anos atrás

Nature 466, 100-104 (1 July 2010) | doi:10.1038/nature09166; Received 29 March 2010; Accepted 4 May 2010

Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago

Abderrazak El Albani1, Stefan Bengtson2, Donald E. Canfield3, Andrey Bekker4, Roberto Macchiarelli5,6, Arnaud Mazurier7, Emma U. Hammarlund2,3,8, Philippe Boulvais9, Jean-Jacques Dupuy10, Claude Fontaine1, Franz T. Fürsich11, François Gauthier-Lafaye12, Philippe Janvier13, Emmanuelle Javaux14, Frantz Ossa Ossa1, Anne-Catherine Pierson-Wickmann9, Armelle Riboulleau15, Paul Sardini1, Daniel Vachard15, Martin Whitehouse16 & Alain Meunier1

Laboratoire HYDRASA, UMR 6269 CNRS-INSU, Université de Poitiers, 86022 Poitiers, France
Department of Palaeozoology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden
Nordic Center for Earth Evolution, DK-5230 Odense M, Denmark
Department of Geological Sciences, University of Manitoba, Manitoba, R3T 2N2 Canada
Département Géosciences, Centre de Microtomographie, Université de Poitiers, 86022 Poitiers, France
Département de Préhistoire, UMR 7194 CNRS, Muséum National d’Histoire Naturelle, Paris, 75005, France
Société Etudes Recherches Matériaux, CRI Biopole, 86000 Poitiers, France
Department of Geological Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
Département Géosciences, UMR 6118, Université de Rennes, 35042 Rennes, France
Bureau de Recherches Géologiques et Minières, 45060 Orléans, France
GeoZentrum Nordbayern, Universität Erlangen, Fachgruppe Paläoumwelt, D 91054 Erlangen, Germany
Laboratoire d'Hydrologie et de Géochimie de Strasbourg, UMR 7517 CNRS, 67084 Strasbourg, France
Département Histoire de la Terre, UMR 7207 CNRS, Muséum National d’Histoire Naturelle, Paris, 75005, France
Département de Géologie, Unité de Recherche Paléobotanique-Paléopalynologie-Micropaléontologie, Université de Liège, Sart-Tilman Liège 4000, Belgium
Laboratoire Géosystèmes, FRE 3298 CNRS, Université Lille 1, 59655 Villeneuve d'Ascq, France
Laboratory for Isotope Geology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden

Correspondence to: Abderrazak El Albani1 Email: abder.albani@univ-poitiers.fr

Reconstruction of a specimen from Gabon showing the peripheral radial fabric

and inner structural organization - Image: A. El Albani

The evidence for macroscopic life during the Palaeoproterozoic era (2.5–1.6 Gyr ago) is controversial1, 2,3, 4, 5. Except for the nearly 2-Gyr–old coil-shaped fossil Grypania spiralis6, 7, which may have been eukaryotic, evidence for morphological and taxonomic biodiversification of macroorganisms only occurs towards the beginning of the Mesoproterozoic era (1.6–1.0 Gyr)8. Here we report the discovery of centimetre-sized structures from the 2.1-Gyr-old black shales of the Palaeoproterozoic Francevillian B Formation in Gabon, which we interpret as highly organized and spatially discrete populations of colonial organisms. The structures are up to 12 cm in size and have characteristic shapes, with a simple but distinct ground pattern of flexible sheets and, usually, a permeating radial fabric. Geochemical analyses suggest that the sediments were deposited under an oxygenated water column. Carbon and sulphur isotopic data indicate that the structures were distinct biogenic objects, fossilized by pyritization early in the formation of the rock. The growth patterns deduced from the fossil morphologies suggest that the organisms showed cell-to-cell signalling and coordinated responses, as is commonly associated with multicellular organization9. The Gabon fossils, occurring after the 2.45–2.32-Gyr increase in atmospheric oxygen concentration10, may be seen as ancient representatives of multicellular life, which expanded so rapidly 1.5 Gyr later, in the Cambrian explosion.

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NOTA CAUSTICANTE DESTE BLOGGER:

Pobre, pobrecito Darwin. Se a explosão Cambriana já era um pé no saco teórico de Darwin, imaginem vida multicelular há 2 bilhões de anos atrás. Possíveis reações da Nomenklatura científica: Nós não esperávamos encontrar tanta complexidade neste período. Isso vai lançar luz na origem e evolução da vida multicelular, talvez não a preconizada pelo gradualismo darwiniano, mas Darwin já tinha preconizado essa possibilidade, y otras cositas mais.

Gente, o que precisa ser encontrado são os quintilhões de quintilhões de elos transicionais para corroborar o fato, Fato, FATO da evolução, mas isso o registro fóssil se recusa em fornecer. O que temos não é ciência, mas retórica vazia para a manutenção do dogma darwiniano. E ai de quem mijar fora do caco de Down...

Fui, nem sei por que, pensando que o registro fóssil tem fósseis que a razão darwiniana teima desconhecer intencionalmente como uma grave anomalia que a teoria não responde com a robustez exigida pelo contexto de justificação teórica.

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Bashar Al-Assad 'falou e disse': os árabes obstaculizam paz no Oriente pelo ódio mortal a Israel

Em Brasília, presidente sírio diz que os árabes obstaculizam paz no Oriente Médio pelo ódio mortal a Israel

Não, não foi isso que disse Bashar al-Assad. Antes, as mesmas potocas árabes que todo mundo de bom senso conhece:

Brasília, 30 jun (EFE).- O presidente da Síria, Bashar al-Assad, disse hoje, em reunião com o presidente Luiz Inácio Lula da Silva, que, apesar dos esforços em busca da paz no Oriente Médio, "Israel sempre põe obstáculos" e "ameaça a região com suas armas nucleares".

Al-Assad foi recebido hoje por Lula em Brasília, na terceira escala de uma viagem pela América Latina que incluiu visitas a Caracas e a Havana e que terminará na sexta-feira em Buenos Aires.

Lula e Bashar na Síria

Durante um almoço oferecido por Lula, o presidente sírio avaliou a oferta de mediação apresentada pelo Brasil para o conflito entre árabes e israelenses e seu apoio à criação de um Estado palestino.

"A Palestina é uma questão muito importante para todos os árabes e a solução dos problemas no Oriente Médio depende disso", declarou Al-Assad, que também destacou o acordo alcançado por Brasil e Turquia com o Irã para a troca de urânio pouco enriquecido por combustível nuclear.

Apesar do acordo não ter convencido as grandes potências e ter sido insuficiente para evitar as novas sanções aprovadas contra o Irã no Conselho de Segurança das Nações Unidas, Al-Assad considerou que serve como base para uma solução negociada ao conflito gerado pelo programa nuclear iraniano.

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Texto integral aqui: Folha de São Paulo

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Para, por e com Israel, sempre!

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Os discípulos de Darwin contemporâneos

Darwin’s Disciples Today

by Carson Holloway

December 18, 2009

As we celebrate the 200th anniversary of Charles Darwin’s birth and the 150th anniversary of the publication of On the Origin of the Species, it is time to realize that the best way to honor his legacy is to fight its over-extension and misapplication into the realm of politics. The second in a two-part series.

Charles Darwin has never had a lack of enemies, but today he is more threatened by his own misguided disciples than by any opponents of science. Consider, in the first place, Peter Singer and his call for A Darwinian Left, published in 1999. Singer’s aim is to convince the Left to drop Karl Marx and take up Charles Darwin as its main source of intellectual inspiration. This change is necessary, Singer holds, because the events of the twentieth century have discredited Marx by revealing his inadequate understanding of human nature. Marx dismissed fears that the creation of an all-powerful communist state would lead to tyranny, because he believed that the social and economic transformation that would make such a state possible would also transform human nature so that tyranny would no longer have to be feared. This was a mistake, and, Singer implies, a responsible Left will have to avoid it by embracing a more realistic account of human nature, such as the one offered by Darwinian biology.

To propose such a change of paradigms, however, raises the question of whether the Left can embrace Darwinism while still remaining the Left. Singer thus has to ask: what is essential to the Left, and is it compatible with Darwinism? In answer to the first question, Singer holds that a certain egalitarianism, or concern with equality, is essential to the Left, specifically a concern with supporting the weak and seeking to ameliorate their condition. In answer to the second question, Singer contends that egalitarianism can be made compatible with Darwinism, but only if that egalitarianism is moderated and made more realistic on the basis of what Darwinism teaches us about human nature. For example, the Left’s egalitarianism teaches it to disapprove the competition of the capitalist economy and the inequalities it produces and to desire a more cooperative arrangement. Singer thinks that such inclinations are compatible with Darwin, because Darwinism teaches that human beings have naturally evolved inclinations toward cooperation. Thus there is something in Darwinian human nature with which the Left can work: it can seek to devise social structures that make it easier for our cooperative inclinations to express themselves. Nevertheless, a Darwinian Left will have to be much more modest in its expectations for such a project. For, unlike the older, Marx-inspired Left, which thought that competition was merely a product of social and economic conditions, a Darwin-inspired Left will recognize that there is a competitive and even selfish streak in human nature itself.

Source: The Darwin Legend

While much of Singer’s argument emphasizes the limitations that Darwinism imposes on Leftist aspirations, there is one area in which he suggests that Darwin has something more positive to contribute to the Left, at least indirectly, by way of debunking the assumptions of its enemies. As an example, Singer brings forward the Biblical idea that God gave man dominion over the lower animals. This belief, Singer contends, still influences our thinking even though it has been “thoroughly refuted by the theory of evolution,” which reveals “a continuum between humans and animals,” with respect to both their physical make up as well as their powers of mind. Animals, Darwin showed, “are capable of love, memory, curiosity, reason, and sympathy for each other.” Darwinism therefore eliminates the basis of the notion that human beings are different in kind from other animals, thus preparing a “revolution in our attitudes” toward them. “Darwinian political thinkers,” he concludes, should therefore “be more inclined to recognize, and base policies on, the similarities we identify between humans and nonhuman animals.”

Singer is well-known as a defender of animal liberation, so it is perhaps not surprising that it is here, in relation to some of his most cherished values, that he asks Darwinism to do the most for him. It is precisely where he asks Darwinism to do the most, however, that Singer goes the most wrong. Knowledge of the continuum between humans and non-human animals is less important to the question of a qualitative difference between the two than Singer thinks. Awareness of that continuum is not, I think, as modern a development as Singer believes. Aristotle was aware of it, as were people in the Middle Ages, who believed in a “great chain of being” in which human beings were down with animals pretty close to the bottom. Indeed, this continuum was surely well appreciated even by pre-modern people who had no knowledge of either Aristotle or medieval philosophy. Most pre-modern people, after all, had experience with domesticated animals and were no doubt well aware of animal capacities for thought and emotion. Yet they all still believed in a qualitative difference between humans and non-human animals. They did so very reasonably, on the commonsense understanding that things can be only incrementally different in many respects and yet still qualitatively different in other respects.

Moreover, Singer is mistaken to think that diminishing the perceived difference between human beings and other animals will result in better human treatment of other animals. If we deny a qualitative difference between ourselves and the beasts, we destroy the basis for assuming qualitatively different obligations to them that go with our special status. Put simply, if we claim that we are not really different than other animals, it is not clear then why we should treat other animals any better than they treat each other. After all, animals themselves are not proponents of animal rights.

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Read more here/Leia mais aqui: The Public Discourse

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NOTA CAUSTICANTE DESTE BLOGGER:

Eu sempre achei que a maneira ardorosa como Darwin é defendido com unhas e dentes pela Nomenklatura científica, galera dos meninos e meninas de Darwin, por ateus e agnósticos, pode muito bem ser 100% caracterizada como 'adoração religiosa'. Tem até 'dogma': seleção natural. Esta não pode ser criticada. Nem cientificamente. Mas, em ciência, nada como um dia atrás do outro. O mito da evolução através da seleção natural está com os dias contados. Quem viver, verá.

Leiam o livro de Søren Løvtrup, Darwinism: The Refutation of a Myth, Croom Helm, Kent, England, 1987. Edição completamente esgotada, e nem em sebos se encontra uma cópia. Eu tenho uma cópia xerocopiada, mas não empresto a ninguém. Vai ser difícil encontrar em alguma biblioteca de nossas universidades. Nitroglicerina epistêmica pura!

Eu? Eu há muito tempo disse adeus a Darwin sem nenhum remorso. Foi em Piracicaba, SP, 1998 após a leitura do livro A caixa preta de Darwin, de Michael Behe: os processos gradualistas darwinianos não explicam a origem e nem a evolução de um 'simples' flagelo bacteriano. Ora, se não explica esta 'simplicidade' como explicar a diversidade e complexidade das coisas vivas [Alô comissão científica que reprovou minha palestra em História da Ciência, eu estou aprendendo!!!)???

Fui, nem sei por que, pensando -- Darwin mesmo tinha dúvidas sobre o que tinha escrito a respeito da origem das espécies (ele nem escreveu sobre a origem das variações) tinha realmente alguma validade científica. Não sou quem está dizendo, foi Darwin quem escreveu isso. Leiam Darwin e se surpreendam...

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Teorias de conspiração na ciência

EMBO reports (2010) 11, 493 - 499
doi:10.1038/embor.2010.84

Published online: 11 June 2010

Subject Categories:
Philosophy & History of Science | Societal Issues & Politics

Conspiracy theories in science

Conspiracy theories that target specific research can have serious consequences for public health and environmental policies

Ted Goertzel

Received 19 March 2010; Accepted 7 May 2010
Introduction

Conspiracy theories are easy to propagate and difficult to refute. Fortunately, until a decade or so ago, few serious conspiracy theories haunted the natural sciences. More recently, however, conspiracy theories have begun to gain ground and, in some cases, have struck a chord with a public already mistrustful of science and government. Conspiracy theorists—some of them scientifically trained—have claimed that the HIV virus is not the cause of AIDS, that global warming is a manipulative hoax and that vaccines and genetically modified foods are unsafe. These claims have already caused serious consequences: misguided public health policies, resistance to energy conservation and alternative energy, and dropping vaccination rates.


Responding to conspiracy theories and ‘sceptics’ draws scientists into arenas where objective information matters less than emotional appeals…

Responding to conspiracy theories and ‘sceptics’ draws scientists into arenas where objective information matters less than emotional appeals, unsupported allegations and unverified speculations. Scientists are understandably reluctant to get bogged down in such debates, but they are sometimes unavoidable when scientists need to voice their concerns in the public arena. It is thus both helpful and important to understand the logic of conspiracy arguments and the best ways to respond to them.

‘Conspiracy’ is an essentially contested rhetorical concept that people apply to different events depending on their point of view (Gallie, 1964). It is almost always pejorative. The Oxford English Dictionary defines conspiracy quite loosely as “an agreement between two or more persons to do something criminal, illegal or reprehensible”. While the law can precisely define the criminal act in any conspiracy, ‘reprehensible’ is in the eye of the beholder. When Hillary Clinton protested that her husband US President Bill Clinton was the victim of a “vast right-wing conspiracy” and US President Lyndon B. Johnson accused the media and liberal activists of a “conspiracy” to oppose his Vietnam War policies, they were intentionally vague as to whether they referred to illegal or merely reprehensible behaviour (Kramer & Gavreili, 2005). Calling something a conspiracy makes it sound much worse than just saying, “people are ganging up on me.”

Invoking the word conspiracy also implies that something is secret and hidden.Pigden (2006) defines a conspiracy as “a secret plan on the part of a group to influence events in part by covert action”. Conspiracies so defined certainly do take place; they are not necessarily a figment of anyone's imagination. These include the failed conspiracy to assassinate Adolf Hitler, the September 11 attacks and the Watergate conspiracy. However, in history and social science, the term ‘conspiracy theory’ usually refers to claims that important events were caused by conspiracies that have heretofore remained undiscovered (Coady, 2006). The claim that the World Trade Center was destroyed by al-Qaeda would not be a conspiracy theory in this sense, but the claim that it was bombed by Israeli agents, or that the American authorities knew about it in advance, would be.


A conspiracy theory gives believers someone tangible to blame for their perceived predicament, instead of blaming it on impersonal or abstract social forces

In the realm of science, the ‘climategate’ scandal that has dogged the University of East Anglia's Climatic Research Unit (CRU; Norwich, UK) has seen the word conspiracy thrown about on both sides of the argument. Climate change ‘sceptics’ have accused Professor Phil Jones of conspiring with his collaborators to manipulate climate data and the scientific literature, while supporters of the CRU have pointed out that the hacking of the e-mails and the selective, pejorative quoting of their content was a conspiracy to discredit the scientific evidence for climate disruption.

Historians and social scientists are generally sceptical of conspiracy theories because they believe that most conspiracies fail and that historical events can be better understood without recourse to unverifiable speculation (Keeley, 2006). Nevertheless, conspiracy theories can get a firm hold among the public at large and their influence seems to be spreading. To understand this success, it is useful to think of conspiracy theorizing as a ‘meme’, a cultural invention that passes from one mind to another and survives, or dies out, through natural selection (Dawkins, 1976). As rhetorical devices, conspiracy theories compete with memes such as ‘fair debate’, ‘scientific expertise’ and ‘resistance to orthodoxy’.

Conspiracy theories appeal to people who are discontented with the established institutions of their society and especially with elites in that society. They are likely to believe that conditions are worsening for people like themselves and that the authorities do not care about them. A conspiracy theory gives believers someone tangible to blame for their perceived predicament, instead of blaming it on impersonal or abstract social forces. The meme becomes a habit of thought: the more people believe in one conspiracy, the more likely they are to believe in others (Goertzel, 1994; Kramer, 1998).

The logic of the conspiracy meme is to question everything the ‘establishment’—be it government or scientists—says or does, even on the most hypothetical and speculative grounds, and to demand immediate, comprehensive and definitive answers to all questions. A failure to give convincing answers is then used as proof of conspiratorial deception. Meanwhile, conspiracy theorists offer their own alternative theories with the flimsiest of evidence, challenging the authorities to prove them wrong.

Of 92 conspiracy theories described in a recent handbook (McConnachie & Tudge, 2008), most targeted political, religious, military, diplomatic or economic elites. These ranged from Tutankhamun and the curse of the Pharaoh to the Protocols of the Elders of Zion, from satanic ritual abuse to the alleged scheming of the Council on Foreign Relations, the Trilateral Commission and the British Royal family. Others involved religious cults, alien abductions or terrorist plots. Some are just amusing, but others fuelled wars, inquisitions and genocides in which millions of people died.


How can we distinguish between the amusing eccentrics, the honestly misguided, the avaricious litigants and the serious sceptics questioning a premature consensus?

The scientific and technological conspiracies listed in the handbook mostly allege the misuse of science by government, the military and large corporations. These include bizarre claims that the military suppressed technology that could make warships invisible; automobile and oil companies have hidden technology that would turn water into gasoline; the military is secretly in cahoots with space aliens; the HIV virus was created deliberately as part of a plot to kill black or gay people; and that dentists seek to poison Americans by putting fluoride in public water supplies. Others claim that corporate officers and public health officials suppressed evidence that preservatives in vaccines cause autism and that silicone breast implants cause connective tissue disease (Specter, 2009; Wallace, 2009).

Other conspiracy theories include claims that a major drug company hid reports that its leading anti-inflammatory drug caused heart attacks and strokes (Specter, 2009); environmental scientists have conspired to keep refereed journals from publishing papers by researchers sceptical that global warming is a crisis (Hayward, 2009;Revkin, 2009); physicians or drug companies have conspired to suppress non-mainstream medical treatments, vitamins and health foods; and that big business and the medical establishment have conspired to obstruct the search for a cure for AIDS so they can continue to sell their ineffective drugs and treatments (Nussbaum, 1990).

Many of these theories are clearly absurd, but some have a veneer of possibility. How can we distinguish between the amusing eccentrics, the honestly misguided, the avaricious litigants and the serious sceptics questioning a premature consensus? No private individual has the time or the expertise to examine the original research literature on each topic, so it is important to have some guidelines for deciding which theories are plausible enough to merit serious examination.

One valuable guideline is to look for cascade logic in conspiracy arguments (Susstein & Vermeule, 2008). This occurs when defenders of one conspiracy theory find it necessary to implicate more and more people whose failure to discover or reveal the conspiracy can only be explained by their alleged complicity. Another guideline is to look for exaggerated claims about the power of the conspirators: claims that are needed to explain how they were able to intimidate so many people and cover their tracks so well. The more vast and more powerful the alleged conspiracy, the less likely that it could have remained undiscovered.

For example, the claim that the moon landing in 1969 was a hoax implies the complicity of thousands of American scientists and technicians as well as of Soviet astronomers and others around the world who tracked the event. It is incredibly implausible that such a conspiracy could have held together. On the contrary, the theory that a few individuals in Richard Nixon's campaign conspired to break into their opponents' offices in the Watergate building was plausible and proved worth investigating and was, indeed, true.

Even if a conspiracy theory is implausible, it can be used as a rhetorical device to appeal to the emotions of a significant public

Even if a conspiracy theory is implausible, it can be used as a rhetorical device to appeal to the emotions of a significant public. The conspiracy meme flourishes best in politics, religion and journalism, in which practitioners can succeed by attracting followers from the general public. These practitioners might actually believe the conspiracy theory, or they might simply use it to win public support.

As long as scientists keep away from politics and controversial social issues, they are largely immune to conspiracy theories because success in scientific careers comes from winning grant applications and publishing significant findings in peer-reviewed journals. Attacking other scientists as conspirators would not be helpful for the careers of most scientists, no matter how frustrated they might be with referees, editors, colleagues or administrators who turn down their manuscripts or grant proposals, or deny them tenure. But conspiracy theories can be useful for scientists who are so far out of the mainstream in their field that they seek to appeal to alternative funding sources or publication outlets. They also might occasionally surface when a scientist's mental health deteriorates to the point that he or she loses touch with reality.

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A metralhadora giratória deste blogger

Nas muitas críticas que recebo na internet tem cada uma. Não faz mal. Como dizia o saudoso e eterno presidente do Corinthíans, Vicente Matheus, quem está na chuva é pra se queimar! Eu deveria ter guardado o link de uma destas pérolas de frases que encontro na Internet: que eu disparo minha metralhadora giratória contra a ciência. Não é contra a ciência, menino ou menina. É contra certa 'ciência', aliás, nem ciência é.

Como não consigo achar este comentário da Galera dos meninos e meninas de Darwin, vai acima a minha versão visual do que realmente faço contra a Nomenklatura científica, sem medo de ser feliz desnudando Darwin e desmascarando o materialismo filosófico que posa como se fosse ciência.

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Um padrão conservado de proporção de cérebros de tubarões a primatas

A conserved pattern of brain scaling from sharks to primates

Kara E. Yopak a,b,1, Thomas J. Lisney c,d, Richard B. Darlington e, Shaun P. Collin d,f, John C. Montgomery b, and Barbara L. Finlay e

-Author Affiliations

aCenter for Scientific Computation in Imaging, University of California, San Diego, CA 92037;
bLeigh Marine Laboratory, University of Auckland, Leigh 0985, New Zealand;
cDepartment of Animal Ecology, Evolutionary Biology Centre, Uppsala University, 752 36 Uppsala, Sweden;
dSchool of Biomedical Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia;
eDepartment of Psychology, Cornell University, Ithaca, NY 14853; and
fSchool of Animal Biology, University of Western Australia, Crawley, Western Australia 6009, Australia

Edited by Charles F. Stevens, Salk Institute for Biological Studies, La Jolla, CA, and approved June 4, 2010 (received for review February 23, 2010)

Abstract

Several patterns of brain allometry previously observed in mammals have been found to hold for sharks and related taxa (chondrichthyans) as well. In each clade, the relative size of brain parts, with the notable exception of the olfactory bulbs, is highly predictable from the total brain size. Compared with total brain mass, each part scales with a characteristic slope, which is highest for the telencephalon and cerebellum. In addition, cerebellar foliation reflects both absolute and relative cerebellar size, in a manner analogous to mammalian cortical gyrification. This conserved pattern of brain scaling suggests that the fundamental brain plan that evolved in early vertebrates permits appropriate scaling in response to a range of factors, including phylogeny and ecology, where neural mass may be added and subtracted without compromising basic function.

chondrichthyan    cerebellar foliation   allometry   mammal    neuroevolution

Footnotes

1To whom correspondence should be addressed. E-mail: kyopak@ucsd.edu.

Author contributions: K.E.Y., R.B.D., and B.F. designed research; K.E.Y., T.J.L., S.P.C., J.C.M., and B.L.F. performed research; K.E.Y. and T.J.L. collected data on chondrichthyan brain organization; S.P.C. and J.C.M. supervised data collection on chondrichthyan brains; R.B.D. analyzed data; and K.E.Y., T.J.L., R.B.D., and B.L.F. wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1002195107/-/DCSupplemental.

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Mudanças na proporção, produção e eficiência metabólica ao longo das principais transições de vida evolucionária

Shifts in metabolic scaling, production, and efficiency across major evolutionary transitions of life

John P. DeLong a,b,1, Jordan G. Okie a, Melanie E. Moses a,c, Richard M. Sibly d, and James H. Brown a,e,1

-Author Affiliations

aDepartment of Biology, University of New Mexico, Albuquerque, NM 87131;
bDepartment of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520;
cDepartment of Computer Science, University of New Mexico, Albuquerque, NM 87131;
dSchool of Biological Sciences, University of Reading, Reading RG6 6AS, United Kingdom; and
e Santa Fe Institute, Santa Fe, NM 87501

Contributed by James H. Brown, June 2, 2010 (sent for review May 15, 2010)

Abstract

The diversification of life involved enormous increases in size and complexity. The evolutionary transitions from prokaryotes to unicellular eukaryotes to metazoans were accompanied by major innovations in metabolic design. Here we show that the scalings of metabolic rate, population growth rate, and production efficiency with body size have changed across the evolutionary transitions. Metabolic rate scales with body mass superlinearly in prokaryotes, linearly in protists, and sublinearly in metazoans, so Kleiber’s 3/4 power scaling law does not apply universally across organisms. The scaling of maximum population growth rate shifts from positive in prokaryotes to negative in protists and metazoans, and the efficiency of production declines across these groups. Major changes in metabolic processes during the early evolution of life overcame existing constraints, exploited new opportunities, and imposed new constraints.

energetic constraints     production efficiency     rmax    endosymbiosis    multicellularity

Footnotes

1To whom correspondence may be addressed. E-mail: john.delong@yale.eduor jhbrown@unm.edu.

Author contributions: J.P.D., J.G.O., M.E.M., R.M.S., and J.H.B. designed research; performed research; analyzed data; and wrote the paper.

The authors declare no conflict of interest.

This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1007783107/-/DCSupplemental.

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Primeiras estrelas

30/6/2010

Agência FAPESP – Muitas das estrelas mais antigas da Via Láctea são remanescentes de outras galáxias menores que foram dilaceradas por colisões violentas há cerca de 5 bilhões de anos. A afirmação é de um grupo internacional de cientistas, em estudo publicado pelo periódico Monthly Notices of the Royal Astronomical Society.

Essas estrelas anciãs são quase tão antigas como o próprio Universo. Os pesquisadores, de instituições da Alemanha, Holanda e Reino Unido, montaram simulações em computadores para tentar recriar cenários existentes na infância da Via Láctea.

Cientistas afirmam que estrelas mais antigas encontradas na Via Láctea são anteriores à própria galáxia, tendo sobrevivido à destruição de seus sistemas originais (divulgação)

O estudo concluiu que as estrelas mais antigas na galáxia, encontradas atualmente em um halo de detritos em torno dela, foram arrancadas de sistemas menores pela força gravitacional gerada pela colisão entre galáxias.

Os cientistas estimam que o Universo inicial era cheio de pequenas galáxias que tiveram existências curtas e violentas. Esses sistemas colidiram entre eles deixando detritos que eventualmente acabaram nas galáxias existentes atualmente.

Segundo os autores, o estudo apoia a teoria de que muitas das mais antigas estrelas da Via Láctea pertenceram originalmente a outras estruturas, não tendo sido as primeiras estrelas a nascer na galáxia da qual a Terra faz parte e que começou a se formar há cerca de 10 bilhões de anos.

“As simulações que fizemos mostram como diferentes relíquias observáveis na galáxia hoje, como essas estrelas anciãs, são relacionadas a eventos no passado distante”, disse Andrew Cooper, do Centro de Cosmologia Computacional da Universidade Durham, no Reino Unido, primeiro autor do estudo.

“Como as camadas antigas de rochas que revelam a história da Terra, o halo estelar preserva o registro do período inicial dramático na vida da Via Láctea, que terminou muito tempo antes de o Sol ser formado”, disse.

As simulações computacionais tomaram como início o Big Bang, há cerca de 13 bilhões de anos, e usaram as leis universais da física para traçar a evolução das estrelas e da matéria negra existente no Universo.

Uma em cada centena de estrelas na Via Láctea faz parte do halo estelar, que é muito mais extenso do que o mais familiar disco em espiral da galáxia.

O estudo é parte do Projeto Aquário, conduzido pelo consórcio Virgem, que tem como objetivo usar as mais complexas simulações feitas em computador para estudar a formação de galáxias.

Monthly Notices of the Royal Astronomical Society: www3.interscience.wiley.com/journal/117974593/home 

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Professores, pesquisadores e alunos de universidades públicas e privadas com acesso ao site CAPES/Periódicos podem ler gratuitamente este artigo da Monthly Notices of the Royal Astronomical Society e de mais 22.440 publicações científicas.

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Análise mitocondrial do genoma revela que as primeiras populações americanas eram mais geneticamente diversas

North America's First Peoples More Genetically Diverse Than Thought, Mitochondrial Genome Analysis Reveals

ScienceDaily (June 29, 2010) — The initial peopling of North America from Asia occurred approximately 15,000-18,000 years ago. However, estimations of the genetic diversity of the first settlers have remained inaccurate. In a report published online inGenome Research, researchers have found that the diversity of the first Americans has been significantly underestimated, underscoring the importance of comprehensive sampling for accurate analysis of human migrations.

New genomic research indicates that the diversity of the first Americans has been significantly underestimated. (Credit: iStockphoto/Jason Lugo)

Substantial evidence suggests that humans first crossed into North America from Asia over a land bridge called Beringia, connecting eastern Siberia and Alaska. Genetic studies have shed light on the initial lineages that entered North America, distinguishing the earliest Native American groups from those that arrived later. However, a clear picture of the number of initial migratory events and routes has been elusive due to incomplete analysis.

In this work, an international group of researchers coordinated by Antonio Torroni of the University of Pavia in Italy performed a detailed mitochondrial genome analysis of a poorly characterized lineage known as C1d. Mitochondrial DNA (mtDNA) is passed down through the maternal lineage, and mtDNA sequence markers are extremely useful tools for mapping ancestry. Similar to other haplogroups that were among the first to arrive in North America, C1d is distributed throughout the continent, suggesting that it may have been also present in the initial founding populations. However, C1d has not been well represented in previous genetic analyses, and the estimated age of approximately 7,000 years, much younger than the other founding haplogroups, was likely inaccurate.

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Read more here/Leia mais aqui: Science Daily

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The initial peopling of the Americas: A growing number of founding mitochondrial genomes from Beringia

Ugo A. Perego1,2, Norman Angerhofer1, Maria Pala2, Anna Olivieri2, Hovirag Lancioni3, Baharak Hooshiar Kashani2, Valeria Carossa2, Jayne E. Ekins1, Alberto Gómez-Carballa4, Gabriela Huber5, Bettina Zimmermann5, Daniel Corach6, Nora Babudri3, Fausto Panara3, Natalie M. Myres1, Walther Parson4,
Ornella Semino2, Antonio Salas5, Scott R. Woodward1, Alessandro Achilli2,3,7,8 and Antonio Torroni2,7,8

+Author Affiliations

1Sorenson Molecular Genealogy Foundation, Salt Lake City, Utah 84115, USA;
2Dipartimento di Genetica e Microbiologia, Università di Pavia, 27100 Pavia, Italy;
3Dipartimento di Biologia Cellulare e Ambientale, Università di Perugia, 06123 Perugia, Italy;
4Unidade de Xenética, Departamento de Anatomía Patolóxica e Ciencias Forenses and Instituto de Medicina Legal, Facultade de Medicina, Universidade de Santiago de Compostela, Santiago de Compostela, Galicia 15782, Spain;
5Institute of Legal Medicine, Innsbruck Medical University, Innsbruck A-6020, Austria;
6Servicio de Huellas Digitales Genéticas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, 1113 Buenos Aires, Argentina

↵7 These authors contributed equally to this work.

Abstract

Pan-American mitochondrial DNA (mtDNA) haplogroup C1 has been recently subdivided into three branches, two of which (C1b and C1c) are characterized by ages and geographical distributions that are indicative of an early arrival from Beringia with Paleo-Indians. In contrast, the estimated ages of C1d—the third subset of C1—looked too young to fit the above scenario. To define the origin of this enigmatic C1 branch, we completely sequenced 63 C1d mitochondrial genomes from a wide range of geographically diverse, mixed, and indigenous American populations. The revised phylogeny not only brings the age of C1d within the range of that of its two sister clades, but reveals that there were two C1d founder genomes for Paleo-Indians. Thus, the recognized maternal founding lineages of Native Americans are at least 15, indicating that the overall number of Beringian or Asian founder mitochondrial genomes will probably increase extensively when all Native American haplogroups reach the same level of phylogenetic and genomic resolution as obtained here for C1d.

Footnotes

↵8 Corresponding authors.

E-mail alessandro.achilli@unipg.it; fax 39-(075)-5855615.

E-mail antonio.torroni@unipv.it; fax 39-(0382)-528496.

[Supplemental material is available online at http://www.genome.org. The sequence data from this study have been submitted to GenBank (http://www.ncbi.nlm.nih.gov/genbank) under accession nos. HM107306–HM107368.]


Article published online before print. Article and publication date are at http://www.genome.org/cgi/doi/10.1101/gr.109231.110.
Received April 16, 2010.
Accepted May 19, 2010.
Copyright © 2010 by Cold Spring Harbor Laboratory Press

Freely available online through the Genome Research Open Access option.

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O mito de Malthus deve desaparecer -- ué, mas Darwin se baseou em Malthus...

Dispelling “the Malthus myth”

Issue: 127
Posted: 25 June 10
Martin Empson

Fred Pearce, Peoplequake: Mass Migration, Ageing Nations and the Coming Population Crash (Eden Project Books, 2010), £12.99

Source/Fonte

In the 200 years since the Reverend Thomas Malthus first penned his tract An Essay on the Principle of Population the question of the “carrying capacity” of the planet has repeatedly appeared. Most recently, mainstream debates around how to solve the question of climate change have boiled down to the simplistic argument that “there are too many people”. James Lovelock for instance argues “that we are treating the planet so badly that we are likely to require a population crash to about one billion people before the world can again live within its ecological means”. The Optimum Population Trust, who “support research into lower optimum population sizes” and “campaign for a lower population in the UK”, claim that “human consumption of renewable resources is already overshooting Earth’s capacity to provide”.

Source/Fonte

This argument fits perfectly with Malthus’s own beliefs. It would have been recognised by writers such as Paul Ehrlich who spent the 1960s warning the world that its rapidly growing population would soon exceed the planet’s ability to provide. It is a recipe that ends up blaming the poorest people for the world’s problems.

The idea that a growing population means a greater pressure on natural resources, which eventually exceeds planetary capacity, is a simple common sense one. It is also wrong. Since Malthus’s time, those who have followed in his footsteps have used such arguments to justify the world’s unequal distribution of wealth and argue against the possibility of social reform. Racism and scapegoating have flowed from the theory and have lead to forced sterilisation programmes, abortion and anti-immigrant legislation. The resurgence of these debates in the context of environmental crisis is a distraction from discussions about the political and economic changes required to tackle global warming.

It is in this context that Fred Pearce’s latest book is such an important contribution. Pearce turns just about every perceived wisdom about population on its head. From the publication of his first writings, Malthus’ ideas rapidly made it into the mainstream. Eugenicists tacked on their ideas of racial superiority to Malthusian concerns and the resultant poisonous mix made the perfect ideology to justify colonialism and empire. Malthus himself had become the first professor of political economy, teaching a generation of future administrators of empire about the “perils of overpopulation” and the “pointlessness of charity”. Charles Trevelyan, who oversaw the Irish Potato famine for the British government, was a student of Malthus.

The same ideas were at the back of Winston Churchill’s mind when he called for the sterilisation of the “feeble-minded”. Between the First and Second World Wars “60,000 imbeciles, epileptics and ‘feeble-minded’ were compulsorily sterilised in the US”, there were tens of thousands of further victims in countries as diverse as Sweden and Japan. The logic was taken to its brutal extreme by the Nazis, who sterilised half a million people, though as Pearce points out, their policies were “widely admired”.

In the post war period, Malthusian ideas were very much part of the ruling ideology of the Cold War. In the early 1950s, the Rockefeller Foundation was set up to ensure that industrial development was held back from countries like India until they had dealt with their population problem. Senior figures in United Nations organisations and Western governments believed that aid shouldn’t be given to “overpopulated” countries, such as Japan, until they had reduced the numbers living there.

But for leading figures in the US administration at this time, concerns about overpopulation were not driven by a desire to improve the lives of the world’s poorest. Rather they saw the issue as a strategic threat to US dominance. One government report concluded that “hungry people without enough land to grow food were likely to be seduced by dreams of land reform”. Such dreams could lead to revolution, and something had to be done. In addition to the introduction of population control programmes, groups like the Rockefeller Foundation funded research into crop improvements—the “green revolution”.

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Read more here/Leia mais aqui: International Socialism

HT/TC: Darwiniana

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DUAS PERGUNTAS IMPERTINENTES DESTE BLOGGER:

1. Se o 'mito' de Malthus deve desaparecer, e Darwin somente após ler Malthus é que pode elaborar uma teoria da evolução através da seleção natural, que devemos fazer com a teoria de Darwin? Considerá-la como um mito também???

2. Isso é para os historiadores de ciência pesquisarem: Qual foi o verdadeiro interesse da Fundação Rockfeller em introduzir a genética no Brasil com o apoio financeiro dado a Theodosius Dobzhansky? Estudar meramente as aberrações genéticas provocadas nas Drosophila melanogaster ou outros interesses econômicos escusos contra o Brasil como os praticados contra a Índia e o Japão??? 

Prof. Dr. Aldo Mellender de Araújo, UFRGS, você pode lançar alguma luz???

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Surpresas da natureza: o design encontrado na natureza é real, não é ilusão

Reação da Nomenklatura científica diante da montanha de evidências de que o design encontrado na natureza é real, não é ilusão! 

Aguenta firme que, à medida que a ciência avançar, mais e mais sinais de design serão descobertos e o atual paradigma científico colapsante não tem como explicar, e já deveria ter saído de cena há muito tempo.

Fui, nem sei por que, pensando na afirmação de que a ciência é a busca pela verdade, que os cientistas devem seguir as evidências aonde elas forem dar, e que nada podemos contra essas verdades, a não ser a favor delas. Eu queria ver a cara do Dawkins, Dennett et caterva.

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Beco evolutivo sem saída nas ilhas Galápagos: divergência de sinais sexuais nos mais raros dos tentilhões de Darwin

Evolutionary Dead End in the Galápagos: Divergence of Sexual Signals in the Rarest of Darwin's Finches

Henrik Brumm1*, Heather Farrington2, Kenneth Petren2,Birgit Fessl3,4

1 Communication and Social Behaviour Group, Max Planck Institute for Ornithology, Seewiesen, Germany, 2 Department of Biological Sciences, University of Cincinnati, Cincinnati, Ohio, United States of America, 3 Charles Darwin Research Station, Puerto Ayora, Santa Cruz, Galápagos, Ecuador, 4Durrell Wildlife Conservation Trust, Jersey, Channel Islands, United Kingdom

Mangrove finch Cactospiza heliobates

Source/Fonte: Darwin Foundation

Abstract Top

Understanding the mechanisms underlying speciation remains a challenge in evolutionary biology. The adaptive radiation of Darwin's finches is a prime example of species formation, and their study has revealed many important insights into evolutionary processes. Here, we report striking differences in mating signals (songs), morphology and genetics between the two remnant populations of Darwin's mangrove finch Camarhynchus heliobates, one of the rarest species in the world. We also show that territorial males exhibited strong discrimination of sexual signals by locality: in response to foreign songs, males responded weaker than to songs from their own population. Female responses were infrequent and weak but gave approximately similar results. Our findings not only suggest speciation in the mangrove finch, thereby providing strong support for the central role of sexual signals during speciation, but they have also implications for the conservation of this iconic bird. If speciation is complete, the eastern species will face imminent extinction, because it has a population size of only 5–10 individuals.

Citation: Brumm H, Farrington H, Petren K, Fessl B (2010) Evolutionary Dead End in the Galápagos: Divergence of Sexual Signals in the Rarest of Darwin's Finches. PLoS ONE 5(6): e11191. doi:10.1371/journal.pone.0011191

Editor: David Reby, University of Sussex, United Kingdom

Received: March 17, 2010; Accepted: May 20, 2010; Published: June 23, 2010

Copyright: © 2010 Brumm et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: Funding was provided by the United Kingdom government's Darwin Initiative Fund (project #15005), the German Research Foundation (award Br 2309/6-1), and the Association for the Study of Animal Behaviour (Christopher Barnard Award for Outstanding Contributions by a New Investigator to HB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

* E-mail: brumm@orn.mpg.de

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More info on the Mangrove finch here/Mais informações sobre o Mangrove finch aqui.

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Por que a seleção natural não pode agir em nível molecular ou genético???

Frontiers in Bioscience 14, 2959-2969, January 1, 2009]

The GS (genetic selection) Principle

David L. Abel

The Gene Emergence Project, The Origin-of-Life Foundation, Inc., 113 Hedgewood Dr. Greenbelt, MD 20770-1610 USA

1. ABSTRACT

The GS (Genetic Selection) Principle states that biological selection must occur at the nucleotide-sequencing molecular-genetic level of 3'5' phosphodiester bond formation. After-the-fact differential survival and reproduction of already-living phenotypic organisms (ordinary natural selection) does not explain polynucleotide prescription and coding. All life depends upon literal genetic algorithms. Even epigenetic and "genomic" factors such as regulation by DNA methylation, histone proteins and microRNAs are ultimately instructed by prior linear digital programming. Biological control requires selection of particular configurable switch-settings to achieve potential function. This occurs largely at the level of nucleotide selection, prior to the realization of any integrated biofunction. Each selection of a nucleotide corresponds to the setting of two formal binary logic gates. The setting of these switches only later determines folding and binding function through minimum-free-energy sinks. These sinks are determined by the primary structure of both the protein itself and the independently prescribed sequencing of chaperones. The GS Principle distinguishes selection of existing function (natural selection) from selection for potential function (formal selection at decision nodes, logic gates and configurable switch-settings).


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FAPESP e agência canadense lançam chamada

29/6/2010

Agência FAPESP – A FAPESP e a AUF, do Canadá, publicam chamada de propostas para selecionar projetos de pesquisa científica e tecnológica cooperativos. As propostas podem ser em todas as áreas do conhecimento, envolvendo o intercâmbio de curta duração de pesquisadores e estudantes participantes nos projetos selecionados.

Os projetos devem ser desenvolvidos por equipes de instituições de ensino superior e de pesquisa do Estado de São Paulo e por pesquisadores associados a instituições de pesquisa ou universidades membros da AUF nas Américas.

Chamada com Agence Universitaire de la Francophonie (AUF) apoiará propostas de pesquisa colaborativa em todas as áreas do conhecimento com intercâmbio de pesquisadores e estudantes (foto: FAPESP)

Os projetos devem envolver o intercâmbio de pesquisadores, de bolsistas de pesquisa em pós-doutoramento e de estudantes bolsistas matriculados em cursos de pós-graduação (a partir do mestrado ou equivalente), participantes dos projetos selecionados.

As propostas dos candidatos do Estado de São Paulo devem ser submetidas à FAPESP e as propostas dos candidatos de instituições de pesquisa ou de universidades membros da AUF nas Américas devem ser submetidas à AUF. Propostas submetidas a apenas uma das agências não serão avaliadas.

A chamada está aberta a dois tipos de modalidades de propostas. A Modalidade I compreende projetos de pesquisa iniciais, com objetivos comuns, nos quais as atividades dos pesquisadores do Estado de São Paulo e dos pesquisadores de estabelecimentos membros da AUF nas Américas serão financiadas, respectivamente, pela FAPESP e pela AUF.

As propostas dos pesquisadores do Estado de São Paulo devem ser apresentadas à FAPESP como propostas de Auxílio à Pesquisa – Regular. As propostas dos pesquisadores de estabelecimentos membros da AUF nas Américas deverão ser apresentadas dentro dos programas regulares da AUF como concessão de subvenção de pesquisa.

A Modalidade II compreende solicitações de recursos suplementares a pesquisa em andamento na FAPESP (Auxílio à Pesquisa – Regular ou Temático, Programa Jovens Pesquisadores em Centros Emergentes ou Centros de Pesquisa, Inovação e Difusão) e apoio a pesquisas em andamento na AUF, para intercâmbio de curta duração de pesquisadores e estudantes bolsistas do Estado de São Paulo.

A chamada prevê o desembolso anual de até US$ 150 mil de parte da FAPESP e igual valor de parte da AUF para o financiamento das propostas selecionadas nas duas modalidades.

As propostas para a chamada FAPESP-AUF (Chamada FAPESP 09/2010) serão recebidas até o dia 28 de outubro de 2010.

Mais informações: www.fapesp.br/acordos/auf

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Descafeinado no pé

29/6/2010

Por Fábio de Castro

Agência FAPESP – Em 2004, um grupo de pesquisadores brasileiros anunciou, em artigo publicado na revista Nature, a descoberta de pés de café desprovidos de cafeína. No entanto, a ideia de explorar comercialmente o café descafeinado natural tem se mostrado frustrada pela baixa produtividade das plantas, provenientes da Etiópia.

Agora, utilizando uma técnica para induzir mutação em sementes, um pesquisador da Universidade Estadual de Campinas (Unicamp) obteve, a partir de sementes de um cafeeiro já utilizado comercialmente, sete plantas mutantes que combinam a produtividade e a ausência de cafeína.

Pesquisador usa método mutagênico para produzir pés de café naturalmente desprovidos de cafeína. Estudo tem apoio da FAPESP (Foto: IAC)

O estudo, apoiado pela FAPESP por meio da modalidade Auxílio à Pesquisa – Regular, foi realizado por Paulo Mazzafera, professor do Departamento de Biologia Vegetal e diretor do Instituto de Biologia da Unicamp. No artigo de 2004, o cientista teve a colaboração de pesquisadores do Instituto Agronômico, de Campinas (SP).

Segundo Mazzafera, seu experimento utilizou sementes do cafeeiro comercial Catuaí Vermelho, da espécie Coffea arabica, que foram tratadas com dois tipos de mutagênicos. As cerca de 28 mil plantas resultantes da germinação foram analisadas por um método qualitativo que identificava a presença ou ausência de cafeína.

“Com o tratamento, obtivemos sete cafeeiros que são praticamente desprovidos de cafeína. São plantas bastante vigorosas que já estão produzindo flores. Já fizemos boa parte das análises bioquímicas e moleculares dessas plantas e procuramos uma empresa brasileira interessada em implantar comercialmente esse café naturalmente descafeinado”, disse à Agência FAPESP.

O cientista explica que o campo experimental onde foi feito o experimento tem atualmente 250 plantas. Com as sementes disponíveis é possível plantar cerca de 5 hectares para testes.

“Se der tudo certo, vamos fazer mudas com essas sementes e levar tudo a campo em 2011”, disse Mazzafera, que é um dos membros da coordenação da área de Agronomia e Veterinária da FAPESP.

Segundo ele, o interesse comercial pelo café descafeinado é pequeno no Brasil, diferentemente do que ocorre em outros países. Menos de 1% do café comercializado em território brasileiro é descafeinado. Enquanto isso, na Europa e nos Estados Unidos, a divulgação dos efeitos adversos da cafeína tem provocado um aumento crescente do mercado de café descafeinado.

“O café descafeinado corresponde a cerca de 10% do total do café comercializado no mundo. Certamente, é um mercado muito interessante e muito valorizado. A alternativa de um café desse segmento que não tem necessidade de passar por processos industriais para ser descafeinado é bastante promissora em termos de mercado”, destacou.

Existem três processos para produção do café descafeinado. O método que emprega o solvente diclorometano, o método suíço, que utiliza água para retirar a cafeína, e o método de gás carbônico supercrítico. “No método suíço, a água retira a cafeína, mas leva junto muitos elementos importantes do café, tendo que ser retornada ao processo. Já o supercrítico exige instalações muito caras”, explicou Mazzafera.

Patente

As plantas obtidas pelo processo só apresentaram um problema: a estrutura de uma flor de café normalmente garante que a planta tenha uma alta taxa de autofecundação – próxima de 95% –, mas a flor da planta mutante abre precocemente, quando ainda está imatura, e, com isso, pode não ter a mesma taxa de autofecundação.

“Como a flor abre antes, em tese ela pode receber pólen de plantas com outros teores de cafeína. O problema, no entanto, não é tão grave, porque podemos plantar lotes de café formados exclusivamente com as plantas mutantes, segregados dos lotes com as plantas normais. Ou podemos colocar abelhas nas plantações do material com baixo teor de cafeína, provocando assim um aumento da taxa de autofecundação entre elas”, disse Mazzafera.

Um dos principais resultados do método que envolveu indução à mutação foi a economia de tempo. “O melhoramento genético tradicional poderia demorar muitos anos para chegar a gerar plantas descafeinadas produtivas”, disse.

O processo mutagênico utilizado para a obtenção das plantas descafeinadas foi patenteado. “No Brasil, não podemos patentear o material, por isso patenteamos o processo. No momento em que uma companhia brasileira se interessar em implantar o café descafeinado natural, poderemos fazer uma patente internacional relativa aos produtos provenientes desse café, cobrando royalties para quem for produzir”, disse

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