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Category: Evolution

At the dawn of life, heat may have driven cell division

At the dawn of life, heat may have driven cell division

Carrie Arnold writes: An elegant ballet of proteins enables modern cells to replicate themselves. During cell division, structural proteins and enzymes coordinate the duplication of DNA, the division of a cell’s cytoplasmic contents, and the cinching of the membrane that cleaves the cell. Getting these processes right is crucial because errors can lead to daughter cells that are abnormal or unviable. Billions of years ago, the same challenge must have faced the first self-organizing membranous bundles of chemicals arising spontaneously…

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How the Western diet has derailed our evolution

How the Western diet has derailed our evolution

Moises Velesquez-Manoff writes: 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…

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Mass extinctions don’t drive evolutionary change — life does

Mass extinctions don’t drive evolutionary change — life does

Riley Black writes: Of all the species that have ever lived on our planet, more than 99 per cent are extinct. Most of these organisms disappeared through the constant shuffle of ecological and evolutionary change. But not all. Many species have vanished in a geological snap during mass extinctions – truly catastrophic events where the rate of extinction vastly outpaces the origin of new species. For a time, these ecological disasters were thought to drive a great flourish of new…

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Imagination: It might be the core of what human brains evolved to do

Imagination: It might be the core of what human brains evolved to do

Philip Ball writes: ‘To me,’ wrote William Blake in 1799, ‘this world is all one continued vision of fancy or imagination.’ The imagination, he later added, ‘is not a state: it is the human existence itself.’ Blake, a painter as well as a poet, created images that acquire their power not only from a certain naive artistic technique, but because they are striving to transcend it – to convey a vision of the world beyond superficial appearances, which only imagination…

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Why I still believe Covid-19 could not have originated in a lab

Why I still believe Covid-19 could not have originated in a lab

By Wendy Orent Where did the Covid-19 pandemic come from? Almost since the beginning of the outbreak, a bitter and explosive controversy has raged over the origins of the novel coronavirus known as SARS-CoV-2. The rapid shut-down of the Huanan Seafood Wholesale Market in Wuhan immediately suggested to Western observers that the Chinese government itself thought that the market was the source, especially since 26 out of 47 of the original cases could be linked to it. An article published…

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The study of the mind needs a Copernican shift in perspective

The study of the mind needs a Copernican shift in perspective

Pamela Lyon writes: In On the Origin of Species (1859), Charles Darwin draws a picture of the long sweep of evolution, from the beginning of life, playing out along two fundamental axes: physical and mental. Body and mind. All living beings, not just some, evolve by natural selection in both ‘corporeal and mental endowments’, he writes. When psychology has accepted this view of nature, Darwin predicts, the science of mind ‘will be based on a new foundation’, the necessarily gradual…

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Ants could help explain why human brains mysteriously shrank thousands of years ago

Ants could help explain why human brains mysteriously shrank thousands of years ago

Science Alert reports: In the 6 million years since our ancestors first branched off from our ancient primate relatives, the volume of the human brain has nearly quadrupled. What many people don’t realize, however, is that sometime after the last ice age, that very brain actually began to shrink. The result is that today, our brains are slightly smaller than those of early humans living 100,000 years ago, and yet no one really knows when or why this happened. Now,…

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Flatworms can reproduce ripping themselves in half

Flatworms can reproduce ripping themselves in half

Ed Yong writes: When planarian flatworms want to reproduce, some have sex. Others, more straightforwardly, tear themselves in two. The latter option is fast and violent. The planarian begins as a small, flattened, sluglike creature with a spade-shaped head and two googly eyes. After a few minutes of stretching and ripping, it separates into two halves—a head and a tail. Within days, the head piece grows a tail. And even more miraculously, the tail regrows its head. “It’s just mind-blowing,”…

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The complex truth about ‘junk DNA’

The complex truth about ‘junk DNA’

Jake Buehler writes: Imagine the human genome as a string stretching out for the length of a football field, with all the genes that encode proteins clustered at the end near your feet. Take two big steps forward; all the protein information is now behind you. The human genome has three billion base pairs in its DNA, but only about 2% of them encode proteins. The rest seems like pointless bloat, a profusion of sequence duplications and genomic dead ends…

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Why the coronavirus has changed as it has, and what it means going forward

Why the coronavirus has changed as it has, and what it means going forward

STAT reports: It’s impossible to say how the coronavirus will continue to evolve. Those changes, after all, are a result of random mutations. But there are some fundamental principles that explain why the virus has morphed as it has, principles that could guide our understanding of its ongoing evolution — and what that means for our future with the pathogen. The great fear is that nature could spit out some new variant that completely saps the power of vaccines and…

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How will the coronavirus evolve?

How will the coronavirus evolve?

Dhruv Khullar writes: In 1988, Richard Lenski, a thirty-one-year-old biologist at UC Irvine, started an experiment. He divided a population of a common bacterium, E. coli, into twelve flasks. Each flask was kept at thirty-seven degrees Celsius, and contained an identical cocktail of water, glucose, and other nutrients. Each day, as the bacteria replicated, Lenski transferred several drops of each cocktail to a new flask, and every so often he stored samples away in a freezer. His goal was to…

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Animals count and use zero. How far does their number sense go?

Animals count and use zero. How far does their number sense go?

Jordana Cepelewicz writes: An understanding of numbers is often viewed as a distinctly human faculty — a hallmark of our intelligence that, along with language, sets us apart from all other animals. But that couldn’t be further from the truth. Honeybees count landmarks when navigating toward sources of nectar. Lionesses tally the number of roars they hear from an intruding pride before deciding whether to attack or retreat. Some ants keep track of their steps; some spiders keep track of…

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Do wild animals get PTSD? Scientists probe its evolutionary roots

Do wild animals get PTSD? Scientists probe its evolutionary roots

By Sharon Levy, Knowable Magazine Every few years, snowshoe hare numbers in the Canadian Yukon climb to a peak. As hare populations increase, so do those of their predators: lynx and coyotes. Then the hare population plummets and predators start to die off. The cycle is a famous phenomenon among ecologists and has been studied since the 1920s. In recent years, though, researchers have come to a startling conclusion: Hare numbers fall from their peak not just because predators eat…

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Great ape interactions indicate that bonobos and chimps follow certain social customs, much like humans

Great ape interactions indicate that bonobos and chimps follow certain social customs, much like humans

Gizmodo reports: You don’t walk up to a coworker without some sort of greeting, and you don’t end conversations simply by turning heel. There are rules to the game of social behavior, and now a research team studying chimpanzees and bonobos say those great apes have social habits that look a lot like what we humans call “hello” and “goodbye.” The research team observed over 2,000 interactions between chimpanzees as well as bonobos, another ape species closely related to humans….

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What misspellings reveal about cultural evolution

What misspellings reveal about cultural evolution

Helena Miton writes: Something about me must remind people of a blind 17th-century poet. My last name, Miton, is French, yet people outside of France invariably misspell it as “Milton”—as in the famed English author, John Milton, of the epic poem Paradise Lost. It is not uncommon for people to misspell an unfamiliar name—yet 99 times out of 100 people misspell mine as “Milton.” That is the name that shows up on everything from my university gym card to emails…

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When did humans start experimenting with psychoactive drugs?

When did humans start experimenting with psychoactive drugs?

Nicholas Longrich, Author provided By Nicholas R. Longrich, University of Bath Humans constantly alter the world. We fire fields, turn forests into farms, and breed plants and animals. But humans don’t just reshape our external world – we engineer our internal worlds, and reshape our minds. One way we do this is by upgrading our mental “software”, so to speak, with myths, religion, philosophy and psychology. The other is to change our mental hardware – our brains. And we do…

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