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POPS"The DNA Code" - Life Hardwired in the Universe The study indicates that you don't need a miracle to arrive at the chemical cocktail for early life, just a decently large asteroid with the right components. That's all. The entire universe could be stuffed with life, from the earliest prebiotic protein-a-likes to fully DNAed descendants. The path from one to the other is long, but we've had thirteen and a half billion years so far and it's happened at least once.
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POPSChemists edge closer to recreating early life Joyce's experiment was designed to test the 'RNA World' theory, which proposes that DNA-based life evolved from a stage whereby RNA acted as both an information-storage molecule, like DNA, and as a catalyst, like enzymes, and was also capable of self-replication. This work is the biggest injection of support for the RNA world hypothesis in a long time,' says Donna Blackmond, Chair in Catalysis at Imperial College London, UK. 'It's a demonstration of principle that indefinite replication, coupled with selection via mutation, is quite plausible for RNA. The fact that it goes on indefinitely is a big thing for showing that this really could have been how life started,' she adds.
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POPSEarth's Original Ancestor Was 'LUCA' The research team compared genetic information from modern organisms to characterize the ancient ancestor of all life on earth. "Our research is much like studying the etymology of modern languages so as to reveal fundamental things about their evolution," says professor Lartillot. "We identified common genetic traits between animals, plant, bacteria, and used them to create a tree of life with branches representing separate species. These all stemmed from the same trunk – LUCA, the genetic makeup that we then further characterized." The group's findings are an important step towards reconciling conflicting ideas about LUCA. In particular, they are much more compatible with the theory of an early RNA world, where early life on Earth was composed of ribonucleic acid (RNA), rather than deoxyribonucleic acid (DNA).
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POPSVolcanic lightning may have sparked life on Earth In the classic Miller-Urey experiment, a mixture of gases and water that Miller thought were present on early Earth was heated and zapped with electricity to mimic lightning. This created five identifiable amino acids. Yet Miller tested three versions of his spark flask. One of the two lesser-know setups – the volcanic apparatus – created 22 amino acids that could be positively identified. The findings could also give clues to life on other planets. The conditions found in the volcanic spark flask could conceivably have once existed on Mars or Titan, and Bada is developing instruments that could detect tiny amounts of amino acids frozen beneath the surface of the Red Planet.
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POPSMapping the Bio Cosmos Microbes are responsible for many biogeochemical cycles and are crucial to the continued function of the , Woese's efforts to clarify the evolution and diversity of microbes provided an invaluable service to ecologists and conservationists. Woese’s big idea is that primitive life existed as a community of cells that freely exchanged genes. They shared a basic translation system for making proteins, but had little else in common. These cells evolved as a community and not as distinct lineages. Before Woese, the tree of life had two main branches called prokaryotes and eukaryotes, the prokaryotes composed of cells without nuclei and the eukaryotes composed of cells with nuclei.
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POPSWill the Internet Evolve into a Lifeform? One route is the evolution of electronic intelligences in situations like the internet-arms race between spammers and shielders. It might sound silly, the idea that new life could be created in an attempt to offer you a great deal on C1@Lis!!, but have you tried registering for a forum recently? Even gaining access to the lowest level of interaction online now requires elementary Turing tests to tell the humans from the robots. Another option is the idea of the net itself becoming sentient, a vast self-modifying array of connections and information storage with limited connections to the outside world (kind of like that glob of grey goo you carry around in your skull). If that happens then Gibson help us all - remember that the net is made of about 90% spam, 9% porn, and quite a lot of whining blogs. If that mixture ever becomes self-aware we're not quite sure what it'll do, but the odds are against it being anything good.
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POPSBiologists on the Verge of Creating New Form of Life "We've made more progress on how the membrane of a protocell could grow and divide," Szostak said in a phone interview. "What we can do now is copy a limited set of simple sequences, but we need to be able to copy arbitrary sequences so that sequences could evolve that do something useful." By doing "something useful" for the cell, these genes would launch the new form of life down the Darwinian evolutionary path similar to the one that our oldest living ancestors must have traveled. Though where selective pressure will lead the new form of life is impossible to know.
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POPSScientists Develop New Computational Method To Investigate Origin Of Life "Retroelements are an ancient and highly diverse class of proteins; therefore, they provide a rigorous benchmark for us to test our approach. We are happy with the results we derived, even though our method is in an early stage," said Patterson. The team plans to make the algorithms that they used in their method available to others as open-source software that is freely available on the Web. Scientists map out the evolutionary histories of organisms by comparing their genetic and/or protein sequences. Those organisms that are closely related and share a recent common ancestor have greater degrees of similarity among their sequences.
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POPSIs our universe fine-tuned for life? Claims of fine-tuning have generally been based on what happens when you vary a single characteristic of the universe, say the strength of gravity, while holding all others constant. That, says Adams, is too artificial a scenario to tell you anything about whether there are other universes that can support life. "The right way to do the problem is to start from scratch," he says. "You have to turn all the knobs and find out what happens."
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POPSBio-Earth: Are Planets Living Super-Organisms? He believes that expanding the study of life sciences to the core of our world and the depths of outer space will help us find distant relatives of our own Earth -- planets that could also sustain life. To explain why contintental plates drift on the surface of the Earth's molten mantle, Maruyama argues that continents actually have life cycles. Old, cold plates on continental fringes sink to “plate graveyards” deep in the Earth’s mantle, and then rise again, creating volcanoes fueled by three-dimensional convection movements deep below the surface.
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POPSUnintelligent Design At this point, 30 years after the Nobel Laureate Daniel Kahneman and his late collaborator Amos Tversky started documenting a rash of fallacies in human reasoning, the idea that the human mind would be "perfect in His image" is as outdated (and narcissistic) as the idea that the solar system would revolve around the planet earth. The only theory that can really make sense of these needless imperfections is Darwin's theory of natural selection, which holds that humans (and all other life forms) evolve through a blind process known as descent-with-modification, in which new life forms represent random modifications of earlier life forms -- with no central overseer to guide the process. Such a random process can, over time, lead populations of creatures to become more adapted to their environment, but it is also vulnerable to getting stuck, in the sort of good-enough-but-not-perfect solutions that mathematicians call local maxima.
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POPSParalysed man takes a walk in virtual world It is the first time a paralysis patient has succeeded in meeting a person and having a conversation in an Internet virtual world, they added. Researchers are now studying a system that would let patients create text messages by mentally selecting certain letters, said Junichi Ushiba, associate professor at the biosciences and informatics department of Keio Universty's Faculty of Science and Technology. "In the near future, they would be able to stroll through Second Life shopping malls with their brain waves... and click to make a purchase," Ushiba said.
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POPSHuge hidden biomass lives deep beneath the oceans They found simple organisms known as prokaryotes in every sample. Prokaryotes are organisms that often have just one cell. Their peculiarity is that, unlike any other form of life, their DNA is not neatly packed into a nucleus.
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