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From Phys.org: Rudimentary life may have existed on Earth 3.95 billion years ago, a time when our infant planet was being bombarded by comets and had hardly any oxygen, researchers said Wednesday. … A team presented what they say is the oldest-known fossil evidence for life on the Blue Planet—grains of graphite, a form of carbon, wedged into ancient sedimentary rocks in Labrador, Canada. … For the new study, Komiya and a team studied graphite, a form of carbon used in pencil lead, in rocks at Saglek Block in Labrador, Canada. They measured its isotope composition, the signature of chemical elements, and concluded the graphite was “biogenic”—meaning it was produced by living organisms. The identity of the organisms, or what Read More ›

From Monya Baker at Nature: Yukiko Yamashita thought she knew the fruit-fly testis inside out. But when she carried out a set of experiments on the organ five years ago, it ended up leaving her flummoxed. Her group had been studying how fruit flies maintain their sperm supply and had engineered certain cells involved in the process to produce specific sets of proteins. But instead of showing up in the engineered cells, some proteins seemed to have teleported to a different group of cells entirely. … But Richard Cheney, a cell biologist at the University of North Carolina in Chapel Hill, is not ready to start revising the textbooks. Cheney has followed the field and at one point collaborated with Read More ›

From Cell: A prevailing view among physiologists is that homeostasis evolves to protect organisms from damaging variation in physiological factors. Here, we propose that homeostasis also evolves to minimize noise in physiological channels. Fluctuations in physiological factors constitute inescapable noise that corrupts the transfer of information through physiological systems. We apply information theory to homeostasis to develop two related ideas. First, homeostatic regulation creates quiet physiological backgrounds for the transmission of all kinds of physiological information. Second, the performance of any homeostatic system influences information processing in other homeostatic systems. This dependence implies that multiple homeostatic systems, embedded within individual organisms, should show strongly nonadditive effects. Paper. (public access) – H. Arthur Woods, J. Keaton Wilson, An information hypothesis for Read More ›

From ScienceDaily: Our visual attention is drawn to parts of a scene that have meaning, rather than to those that are salient or “stick out,” according to new research from the Center for Mind and Brain at the University of California, Davis. The findings, published Sept. 25 in the journal Nature Human Behavior, overturn the widely-held model of visual attention. “A lot of people will have to rethink things,” said Professor John Henderson, who led the research. “The saliency hypothesis really is the dominant view.” Our eyes we perceive a wide field of view in front of us, but we only focus our attention on a small part of this field. How do we decide where to direct our attention, Read More ›

From Michael Byrne at Motherboard: According to a paper published this week in the Monthly Notices of the Royal Astronomical Society, we might just be wrong about all of this. The accelerating expansion may just be a sort of illusion driven by an incorrect assumption about the nature of the distribution of mass across the universe. As cosmological assumptions go, it’s a big one: The universe will remain, on average, smooth and uniform in all locations and from all perspectives. Maybe not? … “While the remarkable isotropy of the CMB points to an initial state with a very high degree of smoothness, the late epoch Universe encompasses a complex cosmic web of structures,” the paper notes. “It is dominated in Read More ›

From Dalmeet Singh Chawla at Nature: Researchers are at odds over when to dub a discovery ‘significant’. In July, 72 researchers took aim at the P value, calling for a lower threshold for the popular but much-maligned statistic. In a response published on 18 September1, a group of 88 researchers have responded, saying that a better solution would be to make academics justify their use of specific P values, rather than adopt another arbitrary threshold. P values have been used as measures of significance for decades, but academics have become increasingly aware of their shortcomings and the potential for abuse. In 2015, one psychology journal banned P values entirely.More. The P-value turns on the question of whether there is any Read More ›

From the Virtual Embryo Project: This $3.2 million, 11-year initiative engaged a team led by Dr. Raymond F. Gasser—one of the leading embryologists of the last half century. His team created thousands of restored, digitized, and labeled serial sections from the world’s largest collection of preserved human embryos. They used these serial sections to create animations, fly-throughs, and 3-D reconstructions. More. Think of it as our personal evolutionary history…

From Jordana Cepelewicz at Quanta: Now, however, researchers led by Alan Rogers, an anthropologist and population geneticist at the University of Utah, have proposed a new genetic model that may reconcile those differences. It concludes that Neanderthals were more numerous than previous genetic studies often supposed, perhaps finally aligning genomic findings with the larger populations extrapolated from artifacts and fossils. It also fills in more of the Neanderthals’ evolutionary history between when they first separated from our ancestors in Africa and when they began to encounter modern humans again during the latter’s own diaspora. In many respects, Neanderthals may have been much more successful as a species — and more like us — than we have usually credited. … More. Read More ›

From ScienceDaily: The sauropod group of dinosaurs included the largest animals that have ever walked the Earth — up to 40 meters long and weighing as much as 90 tons. Evolutionarily speaking, they were obviously very successful, giving rise to a diverse and widely distributed array of plant-eating species. These forms were characterized by a small head, a long and highly flexible neck that allowed them — like modern giraffes — to graze the tops of the tallest trees, and a massive body that made mature specimens invulnerable to predators. The sauropods survived for well over 100 million years before succumbing to the meteorite that snuffed out the dinosaurs at the end of the Cretaceous Era. However, the early representatives Read More ›

Abstract: The archaellum is the macromolecular machinery that Archaea use for propulsion or surface adhesion, enabling them to proliferate and invade new territories. The molecular composition of the archaellum and of the motor that drives it appears to be entirely distinct from that of the functionally equivalent bacterial flagellum and flagellar motor. Yet, the structure of the archaellum machinery is scarcely known. Using combined modes of electron cryo-microscopy (cryoEM), we have solved the structure of the Pyrococcus furiosus archaellum filament at 4.2 Å resolution and visualise the architecture and organisation of its motor complex in situ. This allows us to build a structural model combining the archaellum and its motor complex, paving the way to a molecular understanding of archaeal Read More ›

From Ferris Jabr at Scientific American: Consciousness, most scientists argue, is not a universal property of all matter in the universe. Rather, consciousness is restricted to a subset of animals with relatively complex brains. The more scientists study animal behavior and brain anatomy, however, the more universal consciousness seems to be. A brain as complex as the human brain is definitely not necessary for consciousness. On July 7 this year, a group of neuroscientists convening at Cambridge University signed a document officially declaring that non-human animals, “including all mammals and birds, and many other creatures, including octopuses” are conscious. Jabr makes a useful distinction between “conscious” and “self-aware.” Self-awareness is supposed to reside in the cerebral cortex, which is much Read More ›

From David Klinghoffer at Evolution News & Views: You never know who’s going to turn up at Q&A with Jonathan Wells and John West. The Discovery Institute biologist and political scientist, respectively, answered questions from the audience following a performance of the play Disinherit the Wind in Hollywood, California – which was a pretty interesting event in itself. But then there stands up a biologist from a local university, unidentified, who proceeds to blow everyone away with an account of his experience as a younger man in a formerly Communist country. He explains that under the totalitarian culture of his youth, “Communism was literally welded to Darwinism.” We recorded his remarks and they form a new episode of ID the Read More ›

Abstract: A key innovation for high resolution eyes is a sophisticated lens that precisely focuses light onto photoreceptors. The eyes of holometabolous larvae range from very simple eyes that merely detect light to eyes that are capable of high spatial resolution. Particularly interesting are the bifocal lenses of Thermonectus marmoratus larvae, which differentially focus light on spectrally-distinct retinas. While functional aspects of insect lenses have been relatively well studied, little work has explored their molecular makeup, especially in regard to more complex eye types. To investigate this question, we took a transcriptomic and proteomic approach to identify the major proteins contributing to the principal bifocal lenses of T. marmoratus larvae. Mass spectrometry revealed 10 major lens proteins. Six of these Read More ›

Paper. See also: The multiverse is science’s assisted suicide

J. Scott Turner’s new book, Purpose and Desire: What Makes Something “Alive” and Why Modern Darwinism Has Failed to Explain It here: 1. J. Scott Turner writes, “I have come to believe that there is something presently wrong with how we scientists think about life, its existence, its origins, and its evolution. . . . What’s worse is that being forced to make the choice actually stands in the way of our having a fully coherent theory of life, in all its aspects, most notably its evolution. In other words, this bias is now hindering scientific progress” (p. xi). How does Turner’s claim here strike you? Do you resonate with it at all? Why or why not? 2. Turner describes Read More ›