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STUBBORN RESISTANCE TO IDEAS. “Scientists had considered glaciers as a possible cause of the Great Unconformity before, but the idea had been largely abandoned. A 1973 paper on the idea by University of North Carolina geologist William White failed to garner a single citation by other researchers. Other theories include the impossible (giant tides that wiped the land clean, but would have required the moon to exist hundreds of millions of years earlier than it actually did) and the more reasonable (the uplift and subsequent weathering of a massive supercontinent).” https://lnkd.in/ds7GcBF View in LinkedIn

GLACIAL EROSION THEORY. “The ice would have had to shave only an average of 0.002 inches (0.0625 millimeters) of dirt and rock off the crust each year to accomplish this feat, Keller said. That's a breeze even for modern-day glaciers, he said. Today, erosion rates for continental ice sheets range from 0.004 to 0.19 inches (0.1 to 4.8 mm), with steep mountain glaciers moving nearly 4 inches (100 mm) of rock and dirt annually.” https://lnkd.in/ds7GcBF View in LinkedIn

GLOBALLY VARIABLE. “Keller and his team think that the glaciers of Snowball Earth wiped clean all other impact craters, scraping a bit off the top of Sudbury and Vredefort, too. By their calculations, an average of between 1.8 and 3 vertical miles (3 and 5 km) of crust were scraped away by Snowball Earth's ice sheets over 64 million years. In some spots, Keller said, the loss was greater, and in others, no crust was lost at all.” https://lnkd.in/ds7GcBF View in LinkedIn

CRATER EROSION. “Around 700 million years ago, they found, the Earth's impact craters were wiped nearly clean. Only two huge craters, the Sudbury basin in Canada and the Vredefort crater in South Africa, predate Snowball Earth — and those craters were staggeringly enormous, originally measuring 93 miles (150 km) and 185 miles (300 km) across, respectively. They've been eroded to a fraction of their original size. [Crash! 10 Biggest Impact Craters on Earth].” https://lnkd.in/ds7GcBF View in LinkedIn

UPTICK IN SEDIMENTATION. “Then there’s the huge uptick in sedimentation rates at the start of the Cambrian. All the new sediment required plenty of space to fall into, something that would have only been possible if massive levels of erosion took place beforehand.” https://lnkd.in/ds7GcBF View in LinkedIn

TRANSIENT SPECIES. "The mutation rate delivers a mean time of 18,700 time steps for the creation of new molecular species. The majority of these new mutations are not “fixed” in the population and go extinct very quickly. Occasionally a new species arises that has some advantage over the current dominant species." https://lnkd.in/dryBAUG View in LinkedIn

"NANOBACTERIA-LIKE PARTICLES obtained from human blood are able to withstand high doses of γ-irradiation up to 30 kGy, and no bacterial DNA is found by performing broad-range PCR amplifications." https://lnkd.in/dvNtRzz View in LinkedIn

MOLECULAR DOMINANCE. "More interestingly, we repeatedly observe the emergence of a molecular species that does not self-replicate but drives evolution to a state where the system is dominated for a long period by two co-dependent replicase species that are not self-maintaining. This is a catalytic hypercycle." https://lnkd.in/dryBAUG View in LinkedIn

RAIDING MUTANTS. "In an RNA-world analogue, such as the chemistry we present here, a molecule can act as both template and machine. Initially, two identical molecules come together, with one acting as the machine which makes a copy of the other. Mutants that are better templates subsequently sweep through the population, replacing the initial molecular species." https://lnkd.in/dryBAUG View in LinkedIn

EMERGENT SURPRISES. "We have developed an artificial chemistry that allows self-maintaining molecular systems to mutate and exhibit innovative behaviour. We ran 1,000 open-ended trials and observed an unexpectedly wide range of emergent phenomena, with many parallels to biological systems." https://lnkd.in/dryBAUG View in LinkedIn