terça-feira, 13 de julho de 2010

Como testar o Design Inteligente

A Response to Questions from a Biology Teacher: How Do We Test Intelligent Design?
A biology educator recently wrote me asking how we test intelligent design using the scientific method, how ID is falsifiable, and how ID explains patterns we observe in nature. These are very common questions that we receive all the time from teachers, students, and interested members of the public, and they're usually legitimate, sincere, and thoughtful questions. In this case, they certainly appeared to be such, and below I post a slightly modified version of my response to the teacher, withholding any information about the teacher to protect his/her identity:
Dear [Snip],
Greetings and thanks for your e-mail. ID is most definitely testable and falsifiable. It uses the scientific method and explains many patterns we observe in nature.
Let's start with how ID uses the scientific method. The scientific method is commonly described as a four-step process involving observations, hypothesis, experiments, and conclusion. ID begins with the observation that intelligent agents produce complex and specified information (CSI). Design theorists hypothesize that if a natural object was designed, it will contain high levels of CSI. Scientists then perform experimental tests upon natural objects to determine if they contain complex and specified information. One easily testable form of CSI is irreducible complexity, which can be discovered by experimentally reverse-engineering biological structures to see if they require all of their parts to function. When ID researchers find irreducible complexity in biology, they conclude that such structures were designed.
Regarding testability, ID makes the following testable predictions:
(1) Natural structures will be found that contain many parts arranged in intricate patterns that perform a specific function (e.g. complex and specified information).
(2) Forms containing large amounts of novel information will appear in the fossil record suddenly and without similar precursors.
(3) Convergence will occur routinely. That is, genes and other functional parts will be re-used in different and unrelated organisms.
(4) Much so-called “junk DNA” will turn out to perform valuable functions.
In this regard, ID is falsifiable. When we test these predictions, ID passes those tests. For example:
Regarding prediction 1, natural structures have been found that contain many parts arranged in intricate patterns that perform a specific function (e.g. complex and specified information), such as irreducibly complex machines in the cell. The bacterial flagellum is a prime example. The specified complexity of protein bonds and the simplest self-reproducing cell are other examples. For details, please see Intelligent design (ID) has scientific merit because it uses the scientific method to make its claims and infers design by testing its positive predictions or Asking the Right Questions about the Evolutionary Origin of New Biological Information or you might also enjoy reading the book Signature in the Cell by Cambridge University Ph.D. philosopher of science Stephen C. Meyer.
Regarding prediction 2, biological novelty appears in the fossil record suddenly and without similar precursors. The Cambrian explosion is the prime example. For details, please see Intelligent Design Has Scientific Merit in Paleontology.
Regarding prediction 3, similar parts have been found in organisms that even Darwinists see as separated by more closely related forms that do not contain the similar parts in question. Clear examples include genes controlling eye or limb growth in different organisms whose alleged common ancestors are not thought to have had such forms of eyes or limbs. For details, please see: A Primer on the Tree of Life.
Regarding prediction 4, genetic research continues to uncover functions for “junk-DNA,” include functionality for pseudogenes, introns, LINE, ALU elements, and many other types of "junk DNA." Examples of unknown DNA functions persist, but design encourages researchers to investigate functions, whereas Darwinism has caused some scientists to wrongly assume that non-coding DNA is junk. In fact, ID proponents have been predicting the collapse of the "junk DNA" paradigm for many years. For details, please see: Intelligent Design and the Death of the "Junk-DNA" Neo-Darwinian Paradigm.
These predictions are elaborated in "The Positive Case for Design." In this regard, below is a brief listing of some of the fields where ID provides a framework for predicting, understanding, and explaining the patterns we observe in nature from a wide variety of scientific fields:
• Biochemistry, where ID explains and predicts the presence of high levels of complex and specified information in proteins and DNA;
• Genetics, where ID predicts and explains function for so-called “junk” DNA while neo-Darwinism stifles such research;
• Systematics, where ID explains why there are similarities between living species, including examples of extreme genetic “convergence” that severely conflict with conventional evolutionary phylogenies;
• Cell biology, where ID explains why the cell resembles “designed structures rather than accidental by-products of neo-Darwinian evolution,” allowing scientists to better understand the workings of molecular machines;
• Systems biology, where ID encourages biologists to look at various biological systems as integrated components of larger systems that are designed to work together in a top-down, coordinated fashion, which is what biologists are finding is the case;
• Animal biology, where ID predicts function for allegedly “vestigial” organs, structures, or systems whereas evolution has made many faulty predictions here;
• Bioinformatics, where ID explains the presence of new layers of information and functional language embedded in the genetic codes, as well as other codes within biology;
• Information theory, where ID encourages scientists to understand where intelligent causes are superior to natural causes in producing certain types of information;
• Paleontology, where ID's prediction of irreducibly complexity in biological systems explains paleontological patterns such as the abrupt appearance of biological life forms, punctuated change, and stasis throughout the history of life;
• Physics and Cosmology, where ID encourages scientists to investigate and discover more instances of fine-tuning of the laws of physics and properties of our universe that uniquely allow for the existence of advanced forms of life;
Finally, you might benefit from an Educator's Briefing Packet on Intelligent Design. We don't recommend pushing ID into the curriculum in public schools, so if you're interested in more information on Discovery Institute's recommended science education policy, please visit Discovery Institute's Science Education Policy or feel free to write back seeking more information.
We help many educators to better understand the debate over evolution. Contact us for more information!


Discovery Institute

segunda-feira, 17 de maio de 2010

Vitória dos alunos de Texas!

As escolas texanas poderão agora questionar legalmente muitos aspectos do darwinismo, conforme noticiou o Discovery:

Os pontos mais importantes (em inglês):

1. The adoption of a new critical inquiry standard improving on the old "strengths and weaknesses" language: “in all fields of science, analyze, evaluate and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing including examining all sides of scientific evidence of those scientific explanations so as to encourage critical thinking by the student."
2. The addition of "analyze and evaluate" to all of the high school biology evolution standards (no such language was included in the existing evolution standards). Students are now specifically required to evaluate the evidence regarding major evolutionary topics such as common ancestry, natural selection and mutations.
3. The addition of two new standards in the high school biology evolution section of the TEKS requiring students to analyze and evaluate scientific explanations concerning the fossil record and the complexity of the cell.
4. The adoption of a new high school biology standard dealing with origin of life research and chemical evolution that calls on students to "analyze and evaluate” the scientific evidence regarding formation of DNA molecules.

É isso!

As células e seus poderosos motores

Se uma máquina molecular por si mesma já é uma maravilha, que se dirá de um conjunto delas trabalhando coordenadamente?

Recentes artigos e notícias informam que é exatamente isto o que ocorre nas células vivas: os motores moleculares coordenam seus esforços, ou seja, estão ligados por coordenação, trabalhando para uma determinada função.

Science Daily, por exemplo, publicou uma noticia acerca do assunto, na qual se lia:“inclusive dentro da célula, a mão esquerda sabe o que o esta fazendo a direita”.

Os pesquisadores da Universidade de Virgínia afirmaram “que os motores moleculares funcionam de uma maneira assombrosamente coordenada”, quando umas “simples” algas chamadas Chlamydominas tem que se deslocar por meio de seus flagelos. Isto contradiz modelos anteriores que representavam os motores competindo entre si como num cabo-de-guerra.

"A nova pesquisa da Universidade de Virgínia proporciona sólidas provas de que os motores estão realmentefuncionando em coordenação, todos se movendo em uma direção, como se estivesse sob as mesmas ordens, ou em direção oposta – e novamente, como se estive sob um controle rigoroso.”

É como que imaginar um líder ou supervisor que comanda o processo. Compreender isto poderia servir de ajuda em tratamentos de transtornos neurodegenerativos. O artigo não fez menção da evolução. Os pesquisadores publicaram suas pesquisas PNAS.

Outro sistema celular do qual informava o
Science Daily tem relação com a coordenação de componentes independentes. A transposição de ADN composta de ARN mensageiro sai do núcleo em pequenos motores em 3D, “esticando-se” por um código linear para ser lido pelo ribossomo. E mais uma vez o artigo não diz nada acerca de evolução.

Aos darwinistas cabe agora a dura missão de tentar explicar sob a lógica do acaso (e de seus “aliados”) a ação coordenada de múltiplas peças necessárias para um determinada função, na qual a menor falha de qualquer um de seus componentes, pode levar à doença e até à morte.

Se conseguirem tal proeza sem ginásticas filosóficas e devaneios ateístas, restam-lhe à glória, ou, quiçá, o “Troféu Popper de Epistemologia.”

É isso!

Laib, Marin, Bloodgood and Guilford, «The reciprocal coordination and mechanics of molecular motors in living cells», Proceedings of the National Academy of Sciences EE. UU., publicado en línea el 12 de febrero de 2009, doi: 10.1073/pnas.0809849106.

domingo, 16 de maio de 2010

A imensa complexidade dos vírus

Motor molecular descoberto em vírus
Vide links:

Sabemos que os seres vivos têm que superar os mesmos tipos de problemas físicos encontrados pelos engenheiros. Todavia, os vírus, por definição, não estão vivos: precisam de um hospedeiro para sua replicação. A par disto, pergunto:

1 - Como é possível ter evoluído gradualmente uma bio-nanotecnologia de tão alta precisão como são os vírus?

2 - Como teria se desenvolvido, do ponto de vista MACROevolutivo, motores tão potentes, tão compactos e tão supereficientes como estes?

Vai aqui algo sobre esta interessantíssima desoberta. Não vou postar em inglês, mas em espanhol, para facilitar à leitura (estou um tanto “pachorrento” para tentar traduzir o texto):
“Las cubiertas proteínicas protectoras (cápsides) de los virus son extraordinarios ejemplos de ingeniería biológica de materiales. Estos contenedores sumamente regulares, automontados con dimensiones nanométricas tienen un diseño minimalista, pero combinan unas complejas funciones pasivas y activas. Además de la protección química, están involucrados en el empaquetado selectivo y en la inyección del material genético vírico".
“…extraordinariamente dinámica pero lo suficientemente elástica y resistente para resistir fácilmente la presión conocida de empaquetamiento del ADN (~ 60 atmósferas). Así, estas cápsides no sólo proporcionan un escudo químico, sino también una significativa protección mecánica para sus contenidos genéticos. Las cubiertas víricas son un ejemplo extraordinario de una solución de la naturaleza a un difícil problema de ingeniería de materiales: se automontan para formar fuertes cubiertas de una geometría definida de una forma precisa usando una cantidad mínima de diferentes proteínas."

É isso!