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Category: Evolution

Humans are still evolving thanks to microgenes

Humans are still evolving thanks to microgenes

The Scientist reports: Humans are still evolving new genes, according to a study published in Cell Reports on December 20. As our lineage evolved, at least 155 human genes sprung up from DNA regions previously thought of as “junk,” including two human-specific genes that emerged since humans branched off from chimpanzees around 4 to 6 million years ago, the researchers report. “I thought it was a great study,” says Alan Saghatelian, a biologist at the Salk Institute who was not…

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Inside ancient asteroids, gamma rays made building blocks of life

Inside ancient asteroids, gamma rays made building blocks of life

John Rennie and Allison Parshall write: In 2021, the Hayabusa2 space mission successfully delivered a morsel of the asteroid 162173 Ryugu to Earth — five grams of the oldest, most pristine matter left over from the solar system’s formation 4.5 billion years ago. Last spring, scientists revealed that the chemical composition of the asteroid includes 10 amino acids, the building blocks of proteins. The discovery added to the evidence that the primordial soup from which life on Earth arose may…

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An ancient partnership has helped both plants and fungi thrive over much of Earth

An ancient partnership has helped both plants and fungi thrive over much of Earth

Science reports: As a motley medley of mycologists climbed the basalt slopes of the Lanín volcano earlier this year, the green foliage at lower elevations gave way to autumnal golds and reds. Chile’s famed Araucaria—commonly called monkey puzzle trees—soon appeared, their spiny branches curving jauntily upward like so many cats’ tails. Beneath the majestic trees, the scientists were focused on something far less glamorous—indeed, mostly invisible: mycorrhizal fungi, tiny organisms that intertwine with roots of the Araucaria and nearly all…

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Strange, tentacled microbe may resemble ancestor of complex life

Strange, tentacled microbe may resemble ancestor of complex life

Science reports: By growing an unusual tentacled microbe in the lab, microbiologists may have taken a big step toward resolving the earliest branches on the tree of life and unraveling one of its great mysteries: how the complex cells that make up the human body—and all plants, animals, and many single-celled organisms—first came to be. Such microbes, called Asgard archaea, have previously been cultured—once—but the advance reported today in Nature marks the first time they’ve been grown in high enough…

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World’s oldest DNA discovered, revealing ancient Arctic forest full of mastodons

World’s oldest DNA discovered, revealing ancient Arctic forest full of mastodons

Scientific American reports: The oldest DNA ever recovered has revealed a remarkable two-million-year-old ecosystem in Greenland, including the presence of an unlikely explorer: the mastodon. The DNA, found locked in sediments in a region called Peary Land at the farthest northern reaches of Greenland, shows what life was like in a much warmer period in Earth’s history. The landscape, which is now a harsh polar desert, once hosted trees, caribou and mastodons. Some of the plants and animals that thrived…

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Fossil overturns more than a century of knowledge about the origin of modern birds

Fossil overturns more than a century of knowledge about the origin of modern birds

Science Daily reports: Fossilised fragments of a skeleton, hidden within a rock the size of a grapefruit, have helped upend one of the longest-standing assumptions about the origins of modern birds. Researchers from the University of Cambridge and the Natuurhistorisch Museum Maastricht found that one of the key skull features that characterises 99% of modern birds — a mobile beak — evolved before the mass extinction event that killed all large dinosaurs, 66 million years ago. This finding also suggests…

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Early humans may have cooked fish 780,000 years ago

Early humans may have cooked fish 780,000 years ago

Smithsonian magazine reports: Cooking with fire marked an important turning point in human evolution. But based on available evidence, determining exactly when early humans learned to cook is challenging. While researchers have discovered the remains of charred animals and root vegetables, that doesn’t necessarily mean people were grilling up steaks for dinner; they may have simply tossed a dead animal into the fire for disposal. Now, researchers in Israel say they’ve come up with a clever solution to this problem—and,…

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Parasite gives wolves what it takes to be pack leaders

Parasite gives wolves what it takes to be pack leaders

Nature reports: Wolves infected with a common parasite are more likely than uninfected animals to lead a pack, according to an analysis of more than 200 North American wolves1. Infected animals are also more likely to leave their home packs and strike out on their own. The parasite, Toxoplasma gondii, makes its hosts bold — a mechanism that increases its survival. To reproduce sexually, T. gondii must reach the body of a cat, usually when its host is eaten by…

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Did humans inadvertently produce super insects?

Did humans inadvertently produce super insects?

Lina Zeldovich writes: One day, about 60 million years ago, a little leafcutter moth landed on an ancient sycamore tree to lay eggs in its leaves. The larvae grew, nestled inside a comfy enclosure akin to a sleeping bag made between the leaf’s thin layers. Once hatched, they ate their way through to the surface and left to perpetuate their kin. Most of the chewed-up leaves swirled down to the earth, decomposing shortly after. But this leaf, along with a…

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How supergenes fuel evolution despite harmful mutations

How supergenes fuel evolution despite harmful mutations

Carrie Arnold writes: Thousands of miles from home in the steamy Amazon rainforest in the mid-1800s, the British naturalist Henry Walter Bates had a problem. More than one, really; there were thumb-size biting insects, the ever-present threat of malaria, venomous snakes, and mold and mildew that threatened to overtake his precious specimens before they could be shipped back to England. But the nagging scientific problem that bothered him involved butterflies. Bates had noticed that some of the brightly colored Heliconius…

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Ancient virus may be protecting the human placenta

Ancient virus may be protecting the human placenta

Science reports: About 30 million years ago, a virus infected our primate ancestors and one of its genes got trapped in their genomes. Over time, this viral gene became “domesticated”—and territorial. It helped primates fight off other viruses by preventing them from entering cells. The invader—known as Suppressyn (SUPYN)—is still around today, and it’s still helping us out: A new study reveals that this viral turncoat might help the placenta protect embryos from viral infection. “It’s a beautiful story supported…

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Humans are 8% virus. How the ancient viral DNA in your genome plays a role in human disease and development

Humans are 8% virus. How the ancient viral DNA in your genome plays a role in human disease and development

Pandemics over the course of evolution have led to the integration of viruses into our genome. Westend61via Getty Images By Aidan Burn, Tufts University Remnants of ancient viral pandemics in the form of viral DNA sequences embedded in our genomes are still active in healthy people, according to new research my colleagues and I recently published. HERVs, or human endogenous retroviruses, make up around 8% of the human genome, left behind as a result of infections that humanity’s primate ancestors…

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How xenobots reshape our understanding of genetics

How xenobots reshape our understanding of genetics

Philip Ball writes: Where in the embryo does the person reside? Morphogenesis – the formation of the body from an embryo – once seemed so mystifying that scholars presumed the body must somehow already exist in tiny form at conception. In the 17th century, the Dutch microscopist Nicolaas Hartsoeker illustrated this ‘preformationist’ theory by drawing a foetal homunculus tucked into the head of a sperm. This idea finds modern expression in the notion that the body plan is encoded in…

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What animal intelligence reveals about human stupidity

What animal intelligence reveals about human stupidity

By Rachel Nuwer, August 26, 2022 The German philosopher Friedrich Wilhelm Nietzsche was, by all accounts, a miserable human being. He famously sought meaning through suffering, which he experienced in ample amounts throughout his life. Nietzsche struggled with depression, suicidal ideation, and hallucinations, and when he was 44 — around the height of his philosophical output — he suffered a nervous breakdown. He was committed to a mental hospital and never recovered. Although Nietzsche himself hated fascism and anti-Semitism, his…

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Revelations from 17-million-year-old ape teeth could lead to new insights on early human evolution

Revelations from 17-million-year-old ape teeth could lead to new insights on early human evolution

Fossilised jaws from the 17 million-year-old Kenyan ape Afropithecus turkanensis. Tanya M. Smith/National Museums of Kenya, Author provided By Tanya M. Smith, Griffith University and Daniel Green, Columbia University The timing and intensity of the seasons shapes life all around us, including tool use by birds, the evolutionary diversification of giraffes, and the behaviour of our close primate relatives. Some scientists suggest early humans and their ancestors also evolved due to rapid changes in their environment, but the physical evidence…

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Electric fish genomes reveal how evolution repeats itself

Electric fish genomes reveal how evolution repeats itself

Joanna Thompson writes: Along the murky bottom of the Amazon River, serpentine fish called electric eels scour the gloom for unwary frogs or other small prey. When one swims by, the fish unleash two 600-volt pulses of electricity to stun or kill it. This high-voltage hunting tactic is distinctive, but a handful of other fish species also use electricity: They generate and sense weaker voltages when navigating through muddy, slow-moving waters and when communicating with others of their species through…

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