This Dr.Máximo Sandín an interview, published originally in the blog " Science and Demons", which I transcribe here.
1. In the last decade has seen a boom in the sequencing of genomes of different organisms, which has been that we now have fairly comprehensive databases. How do you think this information can affect the understanding of evolutionary mechanisms?
answer with the words of scientists involved in these sequences: they have had "profound evolutionary consequences." For example, the anemone genome, whose origin is at 700 million years ago, has about 18,000 genes (the man has about 22,000) coding for proteins. Found in anemone genome blocks of DNA that are present in humans in the same provision. Over 80% of their introns are in the same places in humans and have found 283 "genes" in man associated with diseases, including one almost exactly the "gene" BRCA2, allegedly responsible for breast cancer .
In the sea urchin genome, which is 500 million years old, there are these "blocks." The number of protein-coding genes is 23,500! of which share 7077, including those related to vision, smell and hearing but especially the Rag genes (as you know, caused by transposons) involved in the immune response, and many other related genes in humans, with diseases like muscular dystrophy, Huntington's chorea ... No wonder that in the comments these findings in journals such as Science qualify them for "intellectual revolution."
But from the particular perspective of studies directly related to evolution, the sequencing of mammalian genomes have been completely disrupted the ancient phylogenies. Have identified three mammalian superorders: Afrotheria (most African species), Xenarthra (Species from Central and South America) and Laurasiatheria (mainly Eurasian). There is another group than curious, Boreotheria, grouping with Supraprimates Laurasiatheria including rodents and primates. Interestingly, studies of mammalian retrotransposons related to paleontological data indicate an origin "almost simultaneous" of these supercomputers.
To this must be added features of the genome known for some time, that genes are units "discrete", but are composed of fragments of DNA, sometimes with many introns inside, sometimes scattered throughout the genome , and are subjected to "alternative splicing" (transcriptional and posttranscriptional) is a kind of shuffling of their components, so that a sequence can encode hundreds or thousands of different proteins that are expressed differently in each tissue and each time that this expression is controlled by the whole genome, including what was until recently considered "junk" by extremely complex mechanisms (microRNAs, RNA interference, antisense RNA ...) and that this control is determined by the proteome and metabolome, depedientes turn the terms of the cellular environment and, therefore, the external environment. And in the construction genes agencies operating in "Network." All this without the epigenetic inheritance, also dependent on the environment.
The renowned expert in evolutionary developmental biology Stuart A. Newman explains in a very bright, "genes do not uniquely determine what is in the cell, but what is in the cell determines how genes are used"
2. Could you explain why you think the Synthetic Theory, about which there seems to be broad consensus, is inadequate to explain the evolution?
exposure, extremely simplified summary of the empirical findings are real, on the extreme complexity of the control of genetic information would be an insult to the intelligence of the biologists who know the genetic hypothesis is based on the Synthesis "modern" explain why they do not have the slightest connection with reality, but if any person professionally connected with the biology reading this, I'll try to explain in a brief: The assumptions on which was developed at the beginning of last century, genetics population, the backbone of the Synthetic Theory, assumed that genes were discrete entities directly responsible for a character, with two variants, dominant and recessive in a population "of infinite size" the frequencies of these variants respond to the following relationship: p + q = 1, which varied by mutations specific individual and random, which are usually deleterious, but "if" that one of these mutations confer "a benefit" to the wearer, over time would be largely or only in all species. I guess not require a great capacity for reflection to understand that if the empirical data show that this concept of "genes" has no relation to reality, that is, totally false, all preparations made from it will be false, however well go the numbers.
3. Your criticism of "Darwinism" is based, of course, the invalidity of natural selection acting on random mutations as an evolutionary process. However, an organization led by symbiosis, a character acquired by horizontal gene transfer or any other mechanism that is responsible for the generation of new genetic information, is not facing a natural selection for survival in the population?
An organism originated by symbiosis, a character acquired by horizontal transmission or any other phenomenon such as a mirror or a reorganization genomic phenomena that availability of data, not face natural selection would face the most terrible loneliness and misunderstanding (the "hopeful monsters" of Goldschmidt) if that is a single individual. The issue is that there is evidence that these changes may occur in groups of individuals, resulting in a population with these changes. It has been shown experimentally that in the genome are "hot spots" (hot spots), sites tend to insert the moving parts when they change location, which tend to occur duplications or insertions of virus. It also found "hot spots" for horizontal transfer. That is, if these changes can bring up a population with new features, appears and is, natural selection has no role to play in this process.
In fact, no specific data on these sudden changes in populations. In research published last year in Nature , were studied 100 phylogenies of animals, plants and fungi. They found that 78% of the "tree" species appeared sudden events clearly. And ending with a very interesting reflection: "Speciation is Freed from the gradual tug of natural selection, There Need Not Be an 'arms race' between the species and Its environment, standards and Stock events biotic effects."
4. One of the main pillars, and is still in force, Darwin's theory is that any modification, whatever its origin and its size, which increases the probability of reaching reproductive age or improve it, will be positively selected, while an alteration that these factors will diminish the negative. Do you think this concept is wrong in itself, or else is poorly understood in evolutionary biology today?
do not think this concept (if you can call it that) is wrong. It is a truism. Clearly, if a living being has a disease, defect or an unfortunate accident that prevents you from reaching reproductive age, will not play. What I can not imagine from a biological point of view is what type of modification may suffer a living being, whose natural condition is to reach reproductive age (if not, there would be kind) for a "change" increases your chance of reach reproductive age. In any case, it might be a problem mine, but I do not understand what this has to do with genetic and embryological phenomena involved in evolution.
And yes, indeed, think this is one of the "main pillars" of a theory of the evolution of the XXI Century.
5. I think you've postulated that the real architects of evolution are viruses that allow the integration of complete genomes and functional in other organisms. What we can see examples of functions or specific characters that have been achieved through the integration of viral genomes?
can not say I'm the only one to maintain that claim. For example, Carl Woese, Luis Virarreal, Günther Witzany, Patrck Forterre, Nigel Goldenfeld, Philip Hunter, Peer Bork, to name some renowned virologists, microbiologists, have written extensively on this. Of them and some other publications may summarize some of the functions and characters by asking, for example:
- Characteristics of eukaryotic nucleus from bacteria, such as linear chromosomes, telomeres and telomerase, and separation transcript of the translation are of viral origin.
- 10% of the human genome consists endogenous retrovirus expressed in all tissues and organs such as constituent and essential part in both the adult and, especially, in embryonic development.
- The introns have been shown to be of viral origin.
- There is evidence that endogenous retroviruses encoded microRNAs.
- has been shown to possess endogenous virus genome editing capabilities.
- There are hundreds of thousands of scattered fragments of virus genome that are constituents, especially its LTR (long terminal repeats), which are regulators and promoters of other genes.
As the proteome, has been found to be virus-encoded glycosyltransferases, ubiquitin, DNA ligase, ribonucleotide reductase 1, SNF2 global transactivator, inhibitor of apoptosis, chitinase, UDP-glycosyltransferase ... For example, prions, proteins of cellular communication are the genes of the capsid protein (NCp7) of HIV-1, ERVWE1 gene of endogenous retrovirus capsid encoding the syncytin W, proteins responsible for the formation of syncytium-trophoblast, ie involved in placentation ... There is enough literature on it.
But if we keep track of transposons and retrotransposons, seems to have finally recognized as a viral origin, we find that the vast majority of genomes in its real sense, that is complete (repeated sequences, LINEs, SINEs, introns, etc.) are of viral origin.
Overall, it appears to be data that give the virus a worthwhile role in evolution.
6. Viruses as messengers necessarily forces us to think in the history of chicken and the egg, because their genes must have formed in some way how thinks that emerged and developed the first virus or their precursors?
As I try to base my point about empirical data, verifiable, and not on speculation answer a very simple way: I have not the least idea. There are no data to understand when, where and how the virus occurred. Speculation that cellular genes could come from "escaped" for being "selfish" has collapsed with the discovery of millions of viral genes that do not correspond with any genes of living beings. It is known that bacterial virus (phage) were on the Earth with bacteria before life as we know it possible, and that the variety was great from the beginning. As there seemed to be necessary to invent a source to understand their function, must await new data.
7. I Was reading that do not defend the current position of epidemiologists, who tend to consider the interaction between the pathogens as a battle, because these organisms (especially viruses) are the creators of genetic diversity. Am I wrong? How should we proceed then, both preventive and curative, against this type of microorganisms found in all habitats?
I find it very curious when it comes to the current position of "epidemiologists." It's like when talking about the claims of "biologists" because just as there are biologists who believe strongly in certain things, there (habemos) many biologists, and most of those who think, not "believe" in them. For epidemiologists, there are many who blindly follow the dictates of the pharmaceutical industry, but many others, highly qualified, they are very critical of it, for example, mass vaccination campaigns. My contact with this subject and epidemiologists was critical due to the embarrassing (and dangerous) mass vaccination campaign against papillomavirus and the muddy conditions surrounding the granting of the Nobel Zur Hauser as a promotion, but when I inquired about how to develop vaccines understood many things, example, why influenza viruses are hybrids of human and poultry, or with sequences from pigs, have produced vaccines against flu viruses growing human influenza in chicken eggs embrionizados, and the new system is to grow in cell lines. In the one case as in other crops are full of viruses and endogenous retroviruses in full swing. This explains the hybrid viruses. And it also explains why each year, with each new campaign of vaccination, the virus mutates. " Indeed, in the 80 Hillary Koprovsky manufactured in a laboratory of the Congo, a polio vaccine as substrate entire chimpanzee kidneys and green monkey, with its endogenous virus related immunosuppression.
virus's association with certain diseases can be conditioned by the dominant militaristic conception of natural phenomena. It has been shown experimentally that the organs or tissues under stress or "aggression" environment can deliver viral particles. So are associated with diseases such as cancer, arthritis, chronic fatigue syndrome and other associations even more absurd to a viral origin. The conclusion (provisional) you can get from this is that viruses associated with disease virus would have a role in specific organisms and their appearance is due to have been subjected to environmental aggression or some manipulation as described above.
And of course found in all the habitats in sufficient quantities, rather than astronomical and seamlessly integrated with functions in them. For example, in marine waters (I have not seen freshwater studies) have had ten billion viruses per liter, which are involved in controlling the trophic base of the pyramid and to prevent overgrowth of bacteria and algae difficult input from sunlight necessary for marine life and also in key biogeochemical phenomena include the contribution sulfur derivatives produced by its activity to the nucleation of clouds. On the ground the numbers and activities are similar (have had five hundred million viruses per gram of dry soil). According to Carl Woese, a microbiologist arguably the most prestigious current viruses ecosystems "are an important store of genetic information and memory of a community, contributing to the evolutionary dynamics and stability of the system." According to Luis Villareal, University of California, 80% of the genes found in viruses from marine and terrestrial ecosystems do not correspond to any known gene. Also
fear billions of virus (phage) in our digestive system, which are the elements of communication and control of bacterial colonies. Recently, 3.3 million have been sequenced genes (150 times the human genome) belonging to the colonies of bacteria in our gut that are essential for life, ie, they are also our genome.
seems clear that viruses are not pathogenic by definition as it seems, has already been undertaken with the bacteria (it is estimated forty million bacteria in one gram of soil and a million in one milliliter of fresh water, and in our body long estimated that there are ten times more bacteria than cells but probably more). Clearly, if all they were not live for even a second. It also seems clear in light of new data that there are many things about which there is assumed to reflect.
8. Do you have any hypotheses to explain what happened during the so-called Cambrian explosion?, Can you suggest a mechanism that appeared to hit a spectacular diversity in a relatively short time period?
I have an explanation, to me very plausible (though of course I can be wrong) for the Cambrian explosion, real, according to Simon Conway Morris studies, I do not know if it can be considered a hypothesis. What I did was keep track of the data until a (possible) explanation. Attempt to summarize this way:
know that there are viruses that contain coding sequences containing specific biological function in eukaryotes. We know that the retrotransposons, from retroviruses, are responsible for DNA duplications in the genomes. We know that fundamental homeotic genes (there are other small or fragmentary) that control the development of tissues and organs and, of necessity, were present in the Cambrian, are made up tandem repeat sequences in different organisms that differ by the number of duplications as its content, "meaning" would be contained in the original sequence of such duplication (in fact endogenous retroviruses are highly active in developing embryo). This would explain the sudden appearance of various complex organisms from simple ancestors. What is clear is that conservadísimos "blocks" of developmental genes may not have been caused by mutations "randomly" of bacterial genes conservadísimos archaea and eubacteria that can still be identified in eukaryotes. The conclusion (Provisional) is that retroviruses are at the origin of developmental genes and their insertion into the genomes of simple organisms may explain previous, using different combinations of them, the explosion of animal diversity in the Cambrian.
understand that the phenomenon is very complex and difficult to "see" as we have been taught to think "as it should be" evolution, but the data are showing extremely complex biological phenomena seem to point clearly in that direction. I believe that nothing is lost for daring to think about it and maybe they can understand many other phenomena.
9. Now we shall go very far back in time. Science does not yet know for sure how life began on our planet. Do you have any hypothesis to explain how that event occurred?
No. In this case I have no hypothesis. Indeed, there are infrared spectrum data on meteorites with a heavy load of water and organic matter. This spring has been published in Nature the finding that both are not only present but "prevalent" in the asteroid 24 Themis. It seems fairly assumed that the Earth's water comes mostly from meteorites that hit in it (and as we know, the sea water is a real "soup" of bacteria and viruses). I have read magazine articles Astrobiology, Cosmology and Astrophysics who speak quite naturally of the origin of life in outer space. And the bacteria and viruses were on earth before, apparently, that there were conditions for life as we know. We also know that there are bacteria and, of course, the virus that can perfectly withstand radiation from outer space. Will have to wait to have direct data on how it is organized organic matter detected in the asteroids.
10. What your opinion about Intelligent Design is a scientific alternative to Darwinism as its proponents raise or something that belongs to the realm of metaphysics and not science?
scientific activity is to study natural phenomena, materials, to try to understand as much as possible by experiments or observations that are verifiable and reproducible, that is by material explanations based on material facts, and will always be a partial explanation, provisional. (We know there are other paths to knowledge, but in this case we are talking about scientific practice, which is where I work or proposing). Use an abstract and powerful to explain what we find difficult to understand or to explain in today's media is out of scientific practice. The scientific activity is to get to where we take the data and the media, the techniques available and if you can not explain "all" waiting for new data and new technologies allow us to further deepen the knowledge (and that know a lot of physical, for example).
is not supposed to invent scientific explanations or speculations use rhetoric to try to explain "everything" (and so, biologists have long taken an overdose time). Now we have data and ever more profound knowledge, which were unthinkable a few years ago and are showing very different from what was thought when we did not have current technology and can explain, understand many things, but obviously not all. You may not ever get. In any case, we should expect.
11. There are few who claim that science is difficulty in the mythical thinking and pseudoscience. Do you agree with this view?, What would you consider a solution that science is perceived as important by society?
will not be few, but I think they go something clueless. At no time in history (at least in the countries themselves "advanced") science has been so social prestige as the bearer of Truth. There is more to take a look at the big media. For many (perhaps are those "not a few" who feel "harassed") scientific thought is the only modern form of thought. The only way to capture the essence of the world, of reality (which does seem to be in crisis or, at least on the wane in society, it is philosophy.)
To which may refer those who think such a thing is the minority, but growing, critical of certain uses of "science" and the search for alternatives. The enormous capacity of information flow that has occurred as a result of Internet access has produced a wealth of information "questionable" but has also allowed the movement of real news that does not usually appear in mainstream media. For example, about the pernicious effects on health and the environment, tested by scientists, biotech products and its terrible consequences for millions of small farmers. O scandals produced periodically by the terrible side effects (or direct) of certain drugs or pharmaceutical industry practices in the Third World. The obvious economic component behind these industries makes doubt many of the honesty of their intentions because when money and power is through the ethics, truth, including science, resent and as we know, the pharmaceutical industry is one of the three or four more money "generated" in the business world and the "agribusiness" are grabbing control of world food. It is understandable that those who have access to this information try to look for alternatives.
The scientific problem underlying this situation is that both industries seem to continue to base their activities in reductionist conceptions of natural phenomena and competitive vision and "random" of relations between the components of life, and overcome by Scientific research basic call, ie no "applied." Therefore, the attacks on these components of life produce dramatic effects on the body that are not identified as a result of these attacks because they do not know its true function. Therefore, genetic manipulation "blindly" and the use of viruses, transposons and plasmids as "vectors" to enter "genes" strangers in the genomes have unpredictable consequences. Therefore, the "genes" introduced in living transgenic genomic alterations unpredictable and uncontrollable consequences and therefore "escape" of transgenic organisms causing contamination, an irreversible genetic imbalance.
Regarding the second question, try to be shorter. Scientific practice is a wonderful activity. For me, and I guess to most scientists, there is no profession more beautiful, more rewarding personally, to be devoted to the search of knowledge to share with others. And knowledge, every day deeper into the Nature we are showing a reality that surpasses the fantasies of the most creative minds. One World (perhaps a universe), in which each and every one of its components are integrated, coordinated in a network that connects the organic with the inorganic world in which all, absolutely all its components have a role. All contribute (do not say "cooperate" because, as I said before, we've had "overdose" of social applications of concepts of nature) to maintain balanced life and nature has its own means of maintaining this balance. But everything has its limits ...
I think this is what you need to convey to society, not the message of "competence" of "arms race" of "advantages" evolutionary and "the fittest" so that values \u200b\u200bscience as it deserves. And also explain what is science and what is not science (yes, with capitals). Because the technology is not science. It is the application, for practical purposes (economic in our society) of scientific knowledge. But if these applications are made without sufficient knowledge without a clear idea what is being done and without controlling the effects of these manipulations, these assaults on nature become a danger of unpredictable consequences.
I have not tired of repeating this in all places where I could speak and write where I could write, but from my experience, I have the impression that scientific ideas seem to be better understood if written in English, I'm going to use the words of Carl Woese in his article "A New Biology for a New Century" published in 2004 in the journal MICROBIOLOGY AND MOLECULAR BIOLOGY:
A Society That Permits biology to Become an engineering discipline, That Allows Slip Into That science to the role of Changing the World Without living Trying to Understand It, is a danger to itself. Modern Society knows it That Desperately Needs to learn how to live in harmony with the biosphere. Today more than ever We Are in Need of a science of biology That Helps us to do this, shows the way.
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