No, Evolution Is Not Always Dog-Eat-Dog. Violence has been the sire of all the world’s values,” wrote poet Robinson Jeffers in 1940.
“What but the wolf’s tooth whittled so fine the fleet limbs of the antelope? What but fear winged the birds, and hunger jeweled with such eyes the great goshawk’s head?” We’ve taken these metaphors for evolution to heart, reading them to mean that life is a race to kill or be killed. “Darwinian” stands in for “cutthroat,” “survival of the fittest” signifies survival of the ruthless. We see selective pressures that hone each organism for success and drive genetic innovation as the natural order of things. But we know now that that picture is incomplete. One of the best ways to relax selective forces is to work together, something that mathematical biologist Martin Nowak has called the “snuggle for survival.” Evolution Runs Faster on Short Timescales. In the 1950s, the Finnish biologist Björn Kurtén noticed something unusual in the fossilized horses he was studying.
When he compared the shapes of the bones of species separated by only a few generations, he could detect lots of small but significant changes. Horse species separated by millions of years, however, showed far fewer differences in their morphology. Subsequent studies over the next half century found similar effects — organisms appeared to evolve more quickly when biologists tracked them over shorter timescales. Dividing Droplets Could Explain Origin of Life. A Break in the Search for the Origin of Complex Life - The Atlantic. In Norse mythology, humans and our world were created by a pantheon of gods who lived in the realm of Asgard.
As it turns out, these stories have a grain of truth to them. Thanks to a team of scientists led by Thijs Ettema, Asgard is now also the name of a large clan of microbes. Its members, which are named after Norse gods like Odin, Thor, Loki, and Heimdall, are found all over the world. Many of them are rare and no one has actually seen them under a microscope.
But thanks to their DNA, we know they exist. If Ettema is right, then around two billion years ago, an Asgardian microbe (or an incredibly close relative) took part in a unique event that gave rise to the eukaryotes. To understand this story, we have to go back to the very beginning. How Old Is the Modern Human Mind? When I started learning about the Ice Age, the oldest known cave art dated to about 35,000 years ago—now it’s closer to 41,000 years.
And while they seemed like a fairly intelligent species, Neanderthals weren’t thought to have been capable of creating art (the first confirmed Neanderthal cave art—an engraved crosshatch—was announced in 2014). Most researchers didn’t think our ancestors interbred with Neanderthals (but a number of them actually did around 60,000 years ago), and we definitely didn’t know that there was a third separate humanlike species called the Denisovans living in Ice Age Europe—and that some of us carry their genes, too. Without a library of Platonic forms, evolution couldn’t work. When it slithers through the grass, the legless glass lizard is indistinguishable from a snake.
But harass it and it will perform a very un-snakelike feat. It will leave its tail behind – still wriggling – and slide away. That isn’t the only surprise the glass lizard has in store. A careful look also reveals inflexible jaws, movable eyelids, and ear openings. Under Pressure, Does Evolution Evolve? In 1996, Susan Rosenberg, then a young professor at the University of Alberta, undertook a risky and laborious experiment.
Her team painstakingly screened hundreds of thousands of bacterial colonies grown under different conditions, filling the halls outside her lab with tens of thousands of plates of bacteria. “It stank,” Rosenberg recalled with a laugh. “My colleagues hated me.” The biologist, now at Baylor College of Medicine in Houston, hoped to resolve a major debate that had rocked biology in different incarnations for more than 100 years. Meet Luca, the Ancestor of All Living Things. Genes are adapted to an organism’s environment.
So Dr. Martin hoped that by pinpointing the genes likely to have been present in Luca, he would also get a glimpse of where and how Luca lived. “I was flabbergasted at the result, I couldn’t believe it,” he said. The 355 genes pointed quite precisely to an organism that lived in the conditions found in deep sea vents, the gassy, metal-laden, intensely hot plumes caused by seawater interacting with magma erupting through the ocean floor. Deep sea vents are surrounded by exotic life-forms and, with their extreme chemistry, have long seemed places where life might have originated.
How Burgers and Fries Are Killing Your Microbial Balance. For the microbiologist Justin Sonnenburg, that career-defining moment—the discovery that changed the trajectory of his research, inspiring him to study how diet and native microbes shape our risk for disease—came from a village in the African hinterlands.
A group of Italian microbiologists had compared the intestinal microbes of young villagers in Burkina Faso with those of children in Florence, Italy. The villagers, who subsisted on a diet of mostly millet and sorghum, harbored far more microbial diversity than the Florentines, who ate a variant of the refined, Western diet. Where the Florentine microbial community was adapted to protein, fats, and simple sugars, the Burkina Faso microbiome was oriented toward degrading the complex plant carbohydrates we call fiber. “It was the most different human microbiota composition we’d ever seen,” Sonnenburg told me. The Surprising Origins of Life’s Complexity. Charles Darwin was not yet 30 when he got the basic idea for the theory of evolution.
But it wasn’t until he turned 50 that he presented his argument to the world. He spent those two decades methodically compiling evidence for his theory and coming up with responses to every skeptical counterargument he could think of. And the counterargument he anticipated most of all was that the gradual evolutionary process he envisioned could not produce certain complex structures. Do Organisms Become More Evolvable in Times of Stress? Updated on November 18, 2015 Imagine that you wake up in a pit, surrounded by people who are all wounded and bleeding.
Something had clearly gone horribly wrong. Maybe you panic. Maybe you tend to the wounded. Maybe you team up to plan an escape. When Joachim Kurtz from the University of Münster placed healthy beetles among wounded peers, he found that they can unveil mutations that are present in their genomes but whose effects are usually masked. Here’s how it works. Under Pressure, Does Evolution Evolve? The TimeTree of Life Book. Gordon's Introduction to The Earthlife Web. Evogeneao - - Tree of Life. Return to "Download Files" Page You are welcome to download the following graphic image of the Tree of Life for non-commercial, educational purposes: Tree of Life (~3,000 species, based on rRNA sequences) (pdf, 368 KB) (see Science, 2003, 300:1692-1697) This file can be printed as a wall poster. Printing at least 54" wide is recommended. Trees of Life: A Visual History of Evolution.
By Maria Popova. Grand tree of life study shows a clock-like trend in new species emergence and diversity. Temple University researchers have assembled the largest and most accurate tree of life calibrated to time, and surprisingly, it reveals that life has been expanding at a constant rate. "The constant rate of diversification that we have found indicates that the ecological niches of life are not being filled up and saturated," said Temple professor S. Blair Hedges, a member of the research team's study, published in the early online edition of the journal Molecular Biology and Evolution. "This is contrary to the popular alternative model which predicts a slowing down of diversification as niches fill up with species.
" The tree of life compiled by the Temple team is depicted in a new way —- a cosmologically-inspired galaxy of life view —- and contains more than 50,000 species in a tapestry spiraling out from the origin of life. For the massive meta-study effort, researchers painstakingly assembled data from 2,274 molecular studies, with 96 percent published in the last decade. Unintelligent Design.
With the aid of advanced gene sequencing, comparative DNA analysis,and endless cross-referencing of the genomes of organisms from the three—or perhaps four—domains of life, a fuller concept of viruses and their role in evolution has begun to coalesce. In the mere year and a half since Bradfordcoccus's true identity was revealed, more genetically distinct and extremely ancient viruses have been found.
All of them lead scientists to the same conclusion: Evolution's archvillain looks more and more like its vital and formative force. Evolution and the Unintelligent Design of Life: Inherited Traits, Genetic Dysfunction and Artificial Life. Evolution is directionless and blind. Features that evolve at one point can become a hindrance later on. Mutations and inefficiencies leads to dysfunctions and disease. Yeast Study Suggests Genetics Are Random but Evolution Is Not. In his fourth-floor lab at Harvard University, Michael Desai has created hundreds of identical worlds in order to watch evolution at work.
A New Thermodynamics Theory of the Origin of Life. Why does life exist? Evolution: Change: Deep Time. A Brief History of Life. The Evolution of Life on Earth. Atlas of the Human Journey - The Genographic Project. When humans first ventured out of Africa some 60,000 years ago, they left genetic footprints still visible today. The father of all men is 340,000 years old - life - 06 March 2013. Human origins: Are we hybrids? How Many People Have Ever Lived on Earth? "How Many People Have Ever Lived on Earth? " is one of PRB's most popular articles.
The Human Story. Survey of Earliest Human Settlements Undermines Claim That War Has Deep Evolutionary Roots. My last two posts discuss two new studies that contradict the Deep Roots Theory of War, which holds that war is ancient and innate. One study concludes that modern-day mobile foragers (also called nomadic hunter gatherers) are far less warlike than Deep Rooters contend. Early Primate Evolution: Time Scale of the Earth. Chris Stringer on the Origins and Rise of Modern Humans.
By John Noble Wilford, Krishnan Vasudevan and Thomas Lin. Baffling 400,000-Year-Old Clue to Human Origins. Skull of Homo erectus throws story of human evolution into disarray. Tiny, insect-eating animal becomes earliest known primate. A tiny, insect-eating animal with slender limbs, a long tail and weighing in at no more than 30 grams, has become the earliest known primate in the fossil record. Archicebus achilles lived on a humid, tropical lake shore 55m years ago in what is now China and is the ancestor of all modern tarsiers, monkeys, apes and humans.
WATCH: The Surprising Reason We Find Babies Cute. Ecosystems still feel the pain of ancient extinctions - life - 11 August 2013. The Botany of Desire - Full Length High Definition. Bird Study Questions a Driving Force in Evolution. Who’s in Charge Inside Your Head? Sci-Tech / Science : Scientists decode how life emerged from Earth’s abiotics. Extraterresterial Life Exists, Scientist Chandra Wickramasinghe Claims. What Are The Odds Of Finding Extraterrestrial Intelligent Life? 'Radiation-eating' Fungi Finding Could Trigger Recalculation Of Earth's Energy Balance And Help Feed Astronauts. Researchers use Moore's Law to calculate that life began before Earth existed. Astrobiologists discover fossils in meteorite fragments, confirming extraterrestrial life. The truth IS out there: British scientists claim to have found proof of alien life - Science - News. The Single Theory That Could Explain Emergence, Organisation And The Origin of Life.
Chiral Key Found to Origin of Life. Earth's first life may have sprung up in ice - life - 01 November 2013. In Search of Life’s Smoking Gun - Issue 17: Big Bangs. Family trees of ancient bacteria reveal evolutionary moves. Bacteria make major evolutionary shift in the lab - life - 09 June 2008. A New Approach to Building the Tree of Life.