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Preponderance of
Evidence for Naturalistic Origins What is evolution and how does it work? http://evolution.berkeley.edu/evolibrary/search/topicbrowse2.php?topic_id=41 - - - How does evolution impact my life? http://evolution.berkeley.edu/evolibrary/search/topicbrowse2.php?topic_id=47 - - - What is the evidence for evolution? http://evolution.berkeley.edu/evolibrary/search/topicbrowse2.php?topic_id=46 - - - What is the history of evolutionary theory? http://evolution.berkeley.edu/evolibrary/search/topicbrowse2.php?topic_id=48 - - - Evolution evidence rated as top 'breakthrough' of 2005 http://www.msnbc.msn.com/id/10574901/ - - - Evolution, Evidence of http://www.enotes.com/earth-science/evolution-evidence - - - Evolution Primer #1: Isn't Evolution Just a Theory? Evolution Primer #2: Who Was Charles Darwin? Evolution Primer #3: How Do We Know Evolution Happens? Evolution Primer #4: How Does Evolution Really Work? Evolution Primer #5: Did Humans Evolve? Evolution Primer #6: Why Does Evolution Matter Now? Evolution Primer #7: Why Is Evolution Controversial Anyway? (includes some religious apologetics and standard attempts to try to spin the bible & evolution as compatible despite the bible's plethora of anti-scientific & pre-scientific & anti-human & superstitious notions) - - - Clues To A Secret Of Life Found in Meteorite Dust http://www.sciencedaily.com/releases/2009/03/090317153047.htm ScienceDaily (Mar. 18, 2009) - NASA scientists analyzing the dust of meteorites have discovered new clues to a long-standing mystery about how life works on its most basic, molecular level. "We found more support for the idea that biolog- ical molecules, like amino acids, created in space and brought to Earth by meteorite impacts help explain why life is left-handed. ... "By that I mean why all known life uses only left-handed versions of amino acids to build proteins." ... Proteins are the workhorse molecules of life, used in everything from structures like hair to enzymes, the catalysts that speed up or regulate chemical reactions. Just as the 26 letters of the alphabet are arranged in limitless combinations to make words, life uses 20 different amino acids in a huge variety of arrangements to build millions of different pro- teins. Amino acid molecules can be built in two ways that are mirror images of each other, like your hands. Although life based on right-handed amino acids would presumably work fine, "you can't mix them. ... If you do, life turns to something resem- bling scrambled eggs -- it's a mess. Since life doesn't work with a mixture of left-handed and right-handed amino acids, the mystery is: how did life decide -- what made life choose left-handed amino acids over right-handed ones?" ... "Finding more left-handed isovaline in a variety of meteorites supports the theory that amino acids brought to the early Earth by asteroids and comets contributed to the origin of only left-handed based protein life on Earth." ... - - - Elephant Shark Genome Sequence Leads To Discovery of Color Perception In Deep-sea Fish http://www.sciencedaily.com/releases/2009/03/090317162844.htm ScienceDaily (Mar. 18, 2009) - The elephant shark, a primitive deep-sea fish that belongs to the oldest living family of jawed vertebrates, can see color much like humans can. This discovery, published in the March 2009 issue of Genome Research, may enhance scientists' understanding of how color vision evolved in early vertebrates over the last 450 million years of evolution. "It was unexpected that a 'primitive' vertebrate like the elephant shark had the potential for color vision like humans. The discovery shows that it has acquired the traits for color vision during evolution in parallel with humans." ... This finding indicates that the elephant shark had retained more features of the ancestral genome than other verte- brates belonging to the same evolutionary tree and hence was a useful model for gaining insight into the ancestral genome, in which the human genome also has its roots. In several scientific publications, Dr. Venkatesh's team has described research showing that the human DNA sequence was more similar to elephant shark than to any other fish. ... "We expect the sequencing of the whole genome of the elephant shark to be completed by early 2010, the availa- bility of which will then enable scientists to explore the important functional elements in both the human and elephant shark genome that have remained unchanged during the last 450 million years of evolution." - - - Billions Of Years Ago, Microbes Were Key In Developing Modern Nitrogen Cycle http://www.sciencedaily.com/releases/2009/02/090219141436.htm ScienceDaily (Mar. 3, 2009) - As the world marks the 200th anniversary of Charles Darwin's birth, there is much focus on evolution in animals and plants. But new research shows that for the countless billions of tiniest creatures - microbes - large-scale evolution was completed 2.5 billion years ago. "For microbes, it appears that almost all of their major evolution took place before we have any record of them, way back in the dark mists of prehistory." ... All living organisms need nitrogen, a basic component of amino acids and proteins. But for atmospheric nitrogen to be usable, it must be "fixed," or converted to a biologic- ally useful form. Some microbes turn atmospheric nitrogen into ammonia, a form in which the nitrogen can be easily absorbed by other organisms. But the new research shows that about 2.5 billion years ago some microbes evolved that could carry the process a step further, adding oxygen to the ammonia to produce nitrate, which also can be used by organisms. That was the beginning of what today is known as the aerobic nitro- gen cycle. The microbes that accomplished that feat are on the last, or terminal, branches of the bacteria and archaea domains of the so-called tree of life, and they are the only microbes capable of carrying out the step of adding oxygen to am- monia. The fact that they are on those terminal branches indicates that large-scale evolution of bacteria and archaea was com- plete about 2.5 billion years ago. ... The scientists examined material from a half-mile-deep core drilled in the Pilbara region of northwest Australia. They looked specifically at a section of shale from 300 to 650 feet deep, deposited 2.5 billion years ago, and found tell- tale isotope signatures created in the process of denitrifi- cation, the removal of oxygen from nitrate. If denitrification was occurring, then nitrification - the addi- tion of oxygen to ammonia to form nitrate - also must have been taking place. ... That makes the find the earliest solid evidence for the beginning of the aerobic nitrogen cycle. "What this shale deposit has done is record the onset of the modern nitrogen cycle. This was a life-giving nutrient then and remains so today. That's why you put nitrogen fertilizer on your tomato plants, for example." The discovery gives clues about when and how the Earth's atmosphere became oxygen rich. ... - - - Origin of Life On Earth: Scientists Unlock Mystery of Molecular Machine http://www.sciencedaily.com/releases/2009/02/090219105324.htm ScienceDaily (Mar. 1, 2009) - A major mystery about the ori- gins of life has been resolved. According to a study published in the journal Nature, two Université de Montréal scientists have proposed a new theory for how a universal molecular machine, the ribosome, managed to self-assemble as a critical step in the genesis of all life on Earth. "While the ribosome is a complex structure it features a clear hierarchy that emerged based on basic chemical principles." ... "In the absence of such explanations, some people could ima- gine unseen forces at work when such complex structures emerge in nature." What is a ribosome? The ribosome is an enormous molecule responsible for trans- lating the messages carried in the genetic code of all organisms into the workhorse molecules of the cell - proteins - that carry out all functions, including replicating the genome itself. As the world celebrates the bicentennial anniversary of the Father of Evolution, Charles Darwin, Prof. Steinberg's theory brings the scientific community even deeper into the study of the origins of life. By examining the molecular self-organizing processes that pre- ceded the living cell, the point where time begins for biologists, Prof. Steinberg goes further than Darwin and the many evolu- tionary biologists who followed could have imagined. By the standards of biological molecules, ribosomes are immense. Though visible only through lenses of the most powerful micro- scopes, comparing most other biological molecules to this behe- moth is like comparing a tricycle to a jumbo jet. Having spent years gazing at the detailed structure of the ribosome, Prof. Stein- berg pondered how such an immense and complex structure could have assembled itself from smaller building blocks that existed on the early Earth. From the simple to the complex The key breakthrough came when he realized that the ribosome is organized by a set of simple structural rules and that it had to be assembled from basic building blocks in a very specific order; otherwise it would have fallen apart. He then showed with mathe- matical rigor that the construction of the ribosome likely followed an ordered series of steps to form the structure found in the first living cell. To this day, that structure exists almost unchanged in our own cells. Chemists have been able to observe many examples of self-organ- izing behavior with simple molecules, yet explaining the complex self-assembly of biomolecules had not been so obvious. "Thanks to the research of Sergey Steinberg and Konstantin Bo- kov, scientists now have a glimpse of one key event that emerged spontaneously out of the primordial chemical soup of the early Earth." ... "Perhaps in the near future we may look forward to more discov- eries that will take us beyond the world of Darwin into an under- standing of the basic chemical principles that drove the emergence of life on our planet and perhaps beyond." - - - Synthetic Biology Yields Clues To Evolution and Origin Of Life http://www.sciencedaily.com/releases/2009/02/090215151611.htm ScienceDaily (Feb. 25, 2009) - Researchers in the field of synthetic biology are still a long way from being able to assemble living cells from scratch in the laboratory. But according to biochemist David Deamer of the University of California, Santa Cruz, their efforts are yielding clues to the mystery of how life began on Earth. Deamer has been investigating the origin of life for more than 20 years, focusing on the molecular self-assembly processes that led to the first "protocells" nearly 4 billion years ago. ... According to Deamer, life began with com- plex systems of molecules that came together through the self-assembly of nonliving com- ponents. A useful metaphor for understanding how this came about, he said, can be found in combinatorial chemistry, an approach in which thousands of experiments are carried out in parallel by robotic devices. "I look at the origin of life as the result of combinatorial chemistry on a global scale." ... The power of combinatorial chemistry lies in the vast numbers of structurally distinct molecules that can be synthesized and tested at the same time. Similarly, conditions on the early Earth allowed not only the synthe- sis of a wide variety of complex organic mol- ecules, but also the formation of membrane- bound compartments that would have encapsu- lated different combinations of molecules. "We have made protocells in the lab--artifi- cial compartments containing complex systems of molecules. ... The creationists charge that it's too unlikely for the right combin- ation to have come together on its own, but combinatorial chemistry gives us a better way to think about the probability of life emerging from this process." Life began when one or a few protocells hap- pened to have a mix of components that could capture energy and nutrients from the envir- onment and use them to grow and reproduce. Efforts to replicate this process in the laboratory are still in their infancy, but Deamer said he is optimistic that scientists will eventually be able to assemble a living cell from a parts list and thereby achieve a better understanding of how life began. The first forms of life did not evolve in the usual sense, he said, but simply grew. "Evolution began when large populations of cells had variations that led to different metabolic efficiencies," Deamer said. "If the populations were in a confined environ- ment, at some point they would begin to compete for limited resources." The first evolutionary selection processes would have favored those organisms that were most efficient in capturing energy and nutrients from the local environment, he said. - - - Cosmologists Aim To Observe First Moments Of Universe http://www.sciencedaily.com/releases/2009/02/090216092722.htm ScienceDaily (Feb. 17, 2009) - During the next decade, a delicate measurement of primordial light could reveal convincing evidence for the popular cosmic inflation theory, which proposes that a random, microscopic density fluctuation in the fabric of space and time gave birth to the universe in a hot big bang approximately 13.7 billion years ago. ... - - - Draft Version of The Neanderthal Genome Completed http://www.sciencedaily.com/releases/2009/02/090212112731.htm ScienceDaily (Feb. 16, 2009) - Scientists have completed a first draft version of the Neandertal genome. ... The Neandertal genome sequence will clarify the evolutionary relationship between humans and Neandertals as well as help identify those genetic changes that enabled modern humans to leave Africa and rapidly spread around the world, starting around 100,000 years ago. Neandertals were the closest relatives of currently living humans. They lived in Europe and parts of Asia until they became extinct about 30,000 years ago. For more than a hundred years, paleontol- ogists and anthropologists have been striving to uncover their evolutionary relationship to modern humans. ... These DNA sequences can now be compared to the previously sequenced human and chimpanzee genomes in order to arrive at some initial insights into how the genome of this extinct form differed from that of modern humans. ... - - - High-tech Tests Allow Anthropologists to Track Ancient Hominids Across the Landscape http://www.sciencedaily.com/releases/2009/02/090212150838.htm ScienceDaily (Feb. 13, 2009) - Dazzling new scientific techniques are allowing archaeol- ogists to track the movements and menus of extinct hominids through the seasons and years as they ate their way across the African landscape, helping to illuminate the evolution of human diets. Piecing together relationships between the diets of hominids several million years ago to that of early and modern humans is allow- ing scientists to see how diet relates to the evolution of cognitive abilities, social struc- tures, locomotion and even disease. ... "Darwin surmised more than 150 years ago in 'The Descent of Man' that changes in the subsistence or environment of human ancestors likely led to the advent of modern humans. ... Dietary resources can be a force for evolution." ... "Textbooks treat these ancient hominids as static piles of fossil bones. ... We treat them as biological organisms moving across the landscape. It's entirely possible that many things we thought we knew about them were wrong, and pages of textbooks will have to be re-written." - - - Biologists Find Gene Network That Gave Rise To First Tooth http://www.sciencedaily.com/releases/2009/02/090209205101.htm ScienceDaily (Feb. 10, 2009) - Darwin had his finches, Morgan had his fruit flies, and scientists today have cichlid fishes to trace the biological origins of jaws and teeth. ... researchers ... report they have deduced a network of dental genes in cichlids that likely was present to build the first tooth some half a billion years ago. The researchers say their finding lays out a core evolutionary list of molecules needed to make a tooth. These original dental genes, like a four-cylinder Model T engine to the marvels of modern automotive engineering, were then gradually replaced, rewired, or left in place to produce the various shapes and sizes of teeth now found in nature, from shark to mouse to monkey to human. ... - - - Rapidly Evolving Gene Contributes to Origin Of Species http://www.sciencedaily.com/releases/2009/02/090205142134.htm ScienceDaily (Feb. 7, 2009) - A gene that helped one species split into two species shows evidence of adapting much faster than other genes in the genome, raising questions about what is driving its rapid evolution. ... the gene has connections to another pre- viously identified "speciation gene." Both genes code for key proteins that control mol- ecular traffic into and out of a cell's nucleus. The researchers believe an arms race of sorts inside the cell drives these genes to evolve rapidly-and as a consequence makes closely related species genetically incompatible with one another. "When we cross two species of fruit fly, which had split from one another 3 million years ago, some of the hybrid offspring die. ... This tells us that genes from one species are no longer compatible with genes from the other species. We've now found that a functionally related group of genes is responsible, with different versions of the genes having evolved in the two species. And just as Darwin predicted 150 years ago, they evolved by natural selection." Presgraves has some ideas why two of the genes in particular, called Nup160 and Nup96, have evolved so quickly: they act as gatekeepers of a cell's nucleus, a favorite target for viruses and even malicious genes within the fly's own genome. Presgraves says that these genes probably exper- ience constant assault and thus must constantly adapt. That these genes also prevent genetic mix- ing between closely related species is incidental -the origin of new species is just a by-product of evolutionary arms races, he says. - - - Earliest Evidence For Animal Life Discovered: Fossil Animal Steroids Date Back More Than 635 Million Years http://www.sciencedaily.com/releases/2009/02/090204135731.htm ScienceDaily (Feb. 5, 2009) - An international research team of scientists from UC Riverside, the Massachusetts Institute of Technology and other institutions has found the oldest evi- dence for animals in the fossil record. The researchers examined sedimentary rocks in south Oman, and found an anomalously high amount of steroids that date back to 635 million years ago, to around the end of the last ice age. The steroids are produced by sponges - one of the simplest forms of multicellular animals. The researchers argue that the discovery of the sponges is evidence for multicellular animal life beginning 100 million years before the Cambrian explosion, a well-studied and unique episode in Earth history that began about 530 million years ago when, as indicated by the fossil record, ani- mal life diversified rapidly. The discovery can help scientists reconstruct Earth's early ecosystems and explain how animal life may have first evolved on the planet. ... the climatic shock of the extensive glacial episodes of the Neoproterozoic era (1000-542 million years ago) likely caused a major reorg- anization of marine ecosystems, perhaps by irre- vocably altering ocean chemistry. "This paved the way for the evolution of animal feeders living on the seafloor. ... We believe we are converging on the correct date for the diver- gence of complex multicellular animal life, on the shallow ocean floor between 635 and 750 million years ago." ... Next, Love and his colleagues plan to screen other Neoproterozoic sedimentary rocks for ani- mal steroids just before and through the Sturtian and Marinoan glaciations, the greatest ice ages known to have occurred on Earth during 850 to 635 million years ago. "We aim to investigate the environmental context by which multicellular animal life became viable and flourished," he said. ... - - - At 2,500 Pounds And 43 Feet, Prehistoric Snake Is Largest On Record http://www.sciencedaily.com/releases/2009/02/090204112217.htm ScienceDaily (Feb. 4, 2009) - The largest snake the world has ever known -- as long as a school bus and as heavy as a small car -- ruled tropical ecosystems only 6 million years after the demise of the fear- some Tyrannosaurus rex, according to a new discovery published in the journal Nature. ... "The snake's body was so wide that if it were moving down the hall and decided to come into my office to eat me, it would literally have to squeeze through the door." Besides tipping the scales at an estimated 1.25 tons, the snake lived during the Pale- ocene Epoch, a 10-million-year period im- mediately following the extinction of the dinosaurs 65 million years ago, Bloch said. ... - - - How Did Life Begin? RNA That Replicates Itself Indefinitely Developed For First Time http://www.sciencedaily.com/releases/2009/01/090109173205.htm ScienceDaily (Jan. 10, 2009) - One of the most enduring questions is how life could have begun on Earth. Molecules that can make copies of themselves are thought to be crucial to understanding this process as they provide the basis for heritability, a cri- tical characteristic of living systems. New findings could inform biochemical questions about how life began. ... The scientists have synthesized for the first time RNA enzymes that can replicate them- selves without the help of any proteins or other cellular components, and the process proceeds indefinitely. ... In the modern world, DNA carries the genetic sequence for advanced organisms, while RNA is dependent on DNA for performing its roles such as building proteins. But one prominent theory about the origins of life, called the RNA World model, postulates that because RNA can function as both a gene and an enzyme, RNA might have come before DNA and pro- tein and acted as the ancestral molecule of life. ... "This is the only case outside biology where molecular information has been immortalized." ... The research shows that the system can sustain molecular information, a form of heritability, and give rise to variations of itself in a way akin to Darwinian evolution. ... "What we have is non-living, but we've been able to show that it has some life-like properties, and that was extremely interesting." ... He is quick to point out that, while the self- replicating RNA enzyme systems share certain characteristics of life, they are not themselves a form of life. The historical origin of life can never be re- created precisely, so without a reliable time machine, one must instead address the related question of whether life could ever be created in a laboratory. This could, of course, shed light on what the beginning of life might have looked like, at least in outline. "We're not trying to play back the tape ... but it might tell us how you go about starting the process of understanding the emergence of life in the lab." ... - - - Astronomers To Gaze Back In Time and Map History Of Universe http://www.sciencedaily.com/releases/2009/01/090105091528.htm ScienceDaily (Jan. 5, 2009) - UK astronomers are set to expand our knowledge of the history of our Universe with a new project to map the inception and formation of galaxies. ... The primary aim is to chart the distribution of stars and black holes from when the Universe was less than a billion years old to the present day. ... "it is fantastic to see major international astro- nomical facilities both on the ground and in space working in harmony to tackle the fund- amental questions of galaxy formation and evo- lution". - - - (expanded -- end 4 of 4) Posts in this series: Preponderance
of Evidence for Naturalistic Preponderance
of Evidence for Naturalistic Preponderance
of Evidence for Naturalistic Preponderance
of Evidence for Naturalistic
Origins
of Energy, Matter, Space, Time, and Life (2 of 2) - - -
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