Origin Of Life

“Prebiotic” chemistry means the development and demonstration of theories about how chemicals washed together and somehow formed the immensely complex structures of life. There is no shortage of single-event scenarios. A hairpin loop is “an unpaired loop of messenger RNA (mRNA) that is created when an mRNA strand folds and forms base pairs with another section of the same strand. The resulting structure looks like a loop or a U-shape. (Suitable)” In DNA too. From ScienceDaily: The evolution of cells and organisms is thought to have been preceded by a phase in which informational molecules like DNA could be replicated selectively. New work shows that hairpin structures make particularly effective DNA replicator. In the metabolism of all living organisms there Read More ›

From Suzan Mazur at Huffington Post, a chat with molecular biologist Jeffrey Errington about L-form bacteria, which lack a strong cell wall: Jeffery Errington: I became interested in the problem because I was aware of L-forms from the scientific literature of the 1950s and 60s. Curiously, however, right around the end of the 1970s or so, publishing on L-forms just sort of petered out. I haven’t really been able to get to the bottom of exactly why that happened. … Suzan Mazur: How pervasive are L-forms in nature now and earlier in evolution? Jeffery Errington: There are a few bacteria that are naturally cell wall-deficient, like Mycoplasma, which is a pathogen, and Phytoplasma, which inhabits plants. They’re both cell-wall deficient, Read More ›

We’d heard about Craig Venter’s dissent before but you should read the whole story: From Tom Bethell in Darwin’s House of Cards: A Journalist’s Odyssey Through the Darwin Debates, This was publicized in a science forum held at Arizona State University in February 2011, a little over a year after Dawkins’s Greatest Show was published. The physicist Paul Davies and others, including two Nobel Prize winners, participated in the event, which was videotaped. Richard Dawkins himself was on the panel. The forum addressed the question, “What is life?” Most of the panelists accepted that all organisms on Earth represent a single kind of life because they believed that the genetic code is universal. The NASA scientist and panelist Chris McKay Read More ›

Finally, I’ve managed to publish my first blog article! It’s been a rocky start as I had some technical difficulties. Nevertheless, it feels good to get the ball rolling. In this first article, I’ve chosen to take a step back and reflect upon whether or not intelligent design is an important problem to consider in the first place. I outline what I consider to be five strong reasons why this is a matter of great significance.   In the foreword to the intelligent design text, The Design of Life, biochemist William S. Harris notes: The scientific community continues to wrestle with the deep and fundamental questions: Where did the universe come from? How did life originate? How did a coded language (i.e., DNA) Read More ›

At Algemeiner: Question: I’m a little confused here. You have said repeatedly in this lecture and in other lectures, and in your books, that we haven’t the slightest clue how life began. In fact, Christian de Duve himself has stated explicitly that we have no idea how life began. How, then, can he declare that “life is a cosmic imperative?” There is no scientific evidence for that declaration. Answer: Yes, you are correct. However, de Duve and many others like him feel that the odds of life’s starting by chance are so outrageously improbable that it would be irrational even to consider such a possibility. What makes the problem even more difficult is that life would be absurdly improbable even Read More ›

From Ewen Callaway at Nature: A virus that infects bacteria listens to messages from its relatives when deciding how to attack its hosts. Its relatives? These aren’t the viruses we learned about in health and safety class. The discovery — in viruses that attack Bacillus bacteria — marks the first time that any type of viral communication system has ever been found. But researchers say that many other viruses could communicate with each other through their own molecular languages — perhaps even viruses that are responsible for human diseases. If that is the case, scientists might have found a new way to disrupt viral attacks. When levels of arbitrium build up — after a large number of cells have died Read More ›

Recently, we picked up on the story that life on Earth may be datable to 4.1 billion years ago: UCLA geochemists have found evidence that life likely existed on Earth at least 4.1 billion years ago — 300 million years earlier than previous research suggested. The discovery indicates that life may have begun shortly after the planet formed 4.54 billion years ago. The estimate is based on studies of zircons. Zircons? Champagne gemstones on a beer budget? Our favourite physicist and physics colour commentator Rob Sheldon kindly writes to explain why zircons matter to origin of life studies: —- To answer your question, carbon comes in various isotopes or flavors. Giving the longest lasting of these isotopes: Isotope Half-life ——– Read More ›

In a “ so-called Lomagundi Event” when deep sea organic carbon might have suddenly increased between 2.3 and 2.1 billion years ago, ue to “biologically complex, oxygen-breathing animals.” From Colin Barras at New Scientist: “The take-home message is that the oxygen level was high enough to support eukaryotic life and, by some arguments, maybe even animal life,” says Timothy Lyons at the University of California Riverside, who collaborates with Kipp and his colleagues, but was not involved in the new study. … So far, however, it appears there was little response: although there are hints that life became more complex during the Lomagundi Event, there is no really convincing evidence. “But that doesn’t mean that those organisms didn’t exist,” says Read More ›

From ScienceDaily: As they were able to see, the catalysis of the reaction took place when the fatty acids formed compartments. As they are in an aqueous medium, and due to the hydrophobic nature of lipids, they tend to join with each other and form closed compartments; in other words, they take on the function of a membrane; “at that time the membranes obviously weren’t biological but chemical ones,” explained Ruiz-Mirazo. In their experiments they were able to see that the conditions offered by these membranes are favourable for amino acids. “The Montpellier group had the prebiotic reactions of the formation of dipeptides very well characterised, so they were able to see that this reaction took place more efficiently in Read More ›

From the Daily Galaxy: On Earth, simple life appears to have formed quickly, but it likely took many millions of years for very simple life to evolve the ability to photosynthesize. “The early Earth certainly wasn’t a hellish, dry, boiling planet; we see absolutely no evidence for that,” said Harrison [UCLA]. “The planet was probably much more like it is today than previously thought.” UCLA geochemists have found evidence that life likely existed on Earth at least 4.1 billion years ago — 300 million years earlier than previous research suggested. The discovery indicates that life may have begun shortly after the planet formed 4.54 billion years ago. The new research suggests that life existed prior to the massive bombardment of Read More ›

Yet it isn’t happening, and we have no idea how it happened even once… From science writer Michael Gross at Cell: Rapid progress in several research fields relating to the origin of life bring us closer to the point where it may become feasible to recreate coherent and plausible models of early life in the laboratory. (paywall) It’s a survey article, and it concludes: on our own planet and on many others. “One of the main new aspects of origins research is the growing effort to connect chemistry to geology,” Jack Szostak notes. “Finding reasonable geological settings for the origin of life is a critical aspect of understanding the whole pathway. We’ve moved beyond thinking that life emerged from the Read More ›

Phosphorus accumulation changed that, according to a new study. From Ben Brumfield at Georgia Tech News Center: For three billion years or more, the evolution of the first animal life on Earth was ready to happen, practically waiting in the wings. But the breathable oxygen it likely required wasn’t there, and a lack of simple nutrients may have been to blame. Then came a fierce planetary metamorphosis. Roughly 800 million years ago, in the late Proterozoic Eon, phosphorus, a chemical element essential to all life, began to accumulate in shallow ocean zones near coastlines widely considered to be the birthplace of animals and other complex organisms, according to a new study by geoscientists from the Georgia Institute of Technology and Read More ›

Are they or are they not life forms? Note that the article on giant viruses, abstracted below, is public access. Studies in History and Philosophy of Science: Special section on Understanding viruses: Philosophical investigations For example, Understanding viruses: Philosophical investigations: Viruses have been virtually absent from philosophy of biology. In this editorial introduction, we explain why we think viruses are philosophically important. We focus on six issues (the definition of viruses, the individuality and diachronic identity of a virus, the possibility to classify viruses into species, the question of whether viruses are living, the question of whether viruses are organisms, and finally the biological roles of viruses in ecology and evolution), and we show how they relate to classic questions Read More ›

From Joshua S. Weitz and Steven W. Wilhelm at The Scientist (2013, but worth revisiting): There are an estimated 1031 viruses on Earth. That is to say: there may be a hundred million times more viruses on Earth than there are stars in the universe. The majority of these viruses infect microbes, including bacteria, archaea, and microeukaryotes, all of which are vital players in the global fixation and cycling of key elements such as carbon, nitrogen, and phosphorus. These two facts combined—the sheer number of viruses and their intimate relationship with microbial life—suggest that viruses, too, play a critical role in the planet’s biosphere. Of all the Earth’s biomes, the ocean has emerged as the source for major discoveries on Read More ›

There are stories that pop science is bound to tell wrong (you pay/they sneer). Re Hoyle and Wickramasinghe, here’s the skinny: One of them is about “atheist” Fred Hoyle, who was probably more of a panentheist (God is present in everything), according to science historian Michael Flannery: Hoyle is often regarded as a panspermia atheist, and his book The Intelligent Universe (1983) is cited as evidence for this alleged “fact.” Nevertheless, a careful reading of that fascinating book suggests otherwise. While Hoyle did argue for a version of panspermia, he insisted that “The origin of the Universe…requires an intelligence,” and he devoted an entire chapter to this topic. He further stated, “Even after widening the stage for the origin of Read More ›