Archive for the ‘evolution’ category: Page 86

Dec 16, 2018

Evolution Saves Species From ‘Kill the Winner’ Disasters

Posted by in categories: evolution, particle physics

‘’But they noticed an unrealistic defect in the calculations that had traditionally been used in models to validate the KTW idea: They “described populations as if individuals did not exist. It’s as if we described a liquid without acknowledging atoms,” Goldenfeld explained by email.’’

Modelers find evidence that a combination of competition, predation and evolution will push ecosystems toward species diversity anywhere in the universe.

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Dec 11, 2018

These ‘useless’ quirks of evolution are actually evidence for the theory

Posted by in category: evolution

I guess I just feel like venting for a moment… So here goes…

Why are humans the only animals with chins?

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Dec 11, 2018

Rapid genetic evolution linked to lighter skin pigmentation in a southern African population

Posted by in categories: evolution, genetics

Populations of indigenous people in southern Africa carry a gene that causes lighter skin, and scientists have now identified the rapid evolution of this gene in recent human history.

The gene that causes lighter pigmentation, SLC24A5, was introduced from eastern African to southern African populations just 2,000 years ago. Strong positive selection caused this gene to rise in frequency among some KhoeSan populations.

UC Davis anthropologist Brenna Henn and colleagues have shown that a gene for lighter skin spread rapidly among people in southern Africa in the last 2,000 years.

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Dec 6, 2018

Double the stress slows down evolution

Posted by in categories: biotech/medical, evolution, genetics

Neoliberalism slows down evolution! Just kidding…or am I? 🧐😁🤣🙈.

Like other organisms, bacteria constantly have to fight to survive in hostile living conditions. Together with colleagues in Finland, researchers at the Max Planck Institute for Evolutionary Biology in Plön have discovered that bacteria adapt to their environment more slowly and less efficiently as soon as they are exposed to two stress factors rather than one. This is due to mutations in different genes. The slower rate of evolution led to smaller population sizes. This means that evolution can take divergent paths if an organism is exposed to several stress factors.

Bacteria rarely live alone; they are usually part of a community of species that is exposed to various stress factors. They can often react to these factors by adapting to new environmental conditions with astonishing speed. Antibiotics that enter soil and water via and accumulate there in low concentrations can trigger the evolution of resistance in – even though these concentrations are so low that they inhibit only slightly or not at all. However, bacteria do not only have to fight ; they also have to deal with predators. This is why they often grow in large colonies that cannot be consumed by predatory organisms.

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Dec 5, 2018

The Transhuman Revolution: What it is and How to Prepare for its Arrival

Posted by in categories: biological, evolution, transhumanism

What would it be like to live through our own species’ evolution? The biological process of natural selection that gave rise to every species on Earth takes hundreds of generations to turn one species into another, but what if that process could be skipped entirely?

A look at the future of transhumanist technologies and what their evolution will mean for our society.

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Dec 3, 2018

Evolution sans mutation discovered in single-celled archaea

Posted by in categories: biotech/medical, evolution, genetics

I just love it when the reductionists are wrong…again. I can not help myself. bigsmile

University of Nebraska-Lincoln researchers have found revolutionary evidence that an evolutionary phenomenon at work in complex organisms is at play in their single-celled counterparts, too.

Species most often evolve through DNA mutations inherited by successive generations. A few decades ago, researchers began discovering that multicellular species can also evolve through epigenetics: traits originating from the inheritance of cellular proteins that control access to an organism’s DNA, rather than genetic changes.

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Nov 25, 2018

A Bold New Strategy for Stopping the Rise of Superbugs

Posted by in categories: biotech/medical, evolution

Over the past 90 years, scientists have discovered hundreds of antibiotics—microbe-killing drugs that have brought many pernicious diseases to heel. But every time researchers identify a new drug, bacteria inevitably evolve to resist it within a matter of years. We thrust; they parry. Now, with the flow of new antibiotics having dried up for decades, our stalemated duel with infectious bacteria threatens to end in outright defeat. Superbugs are ascendant around the world, including those that resist all commonly used drugs.

Scientists have pinpointed a molecule that accelerates the evolution of drug-resistant microbes. Now they’re trying to find a way to block it.

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Nov 22, 2018

Spotting nature’s own evolution of quantum tricks could transform quantum technology

Posted by in categories: evolution, quantum physics

A new test to spot where the ability to exploit the power of quantum mechanics has evolved in nature has been developed by physicists at the University of Warwick.

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Nov 20, 2018

Colorful Asteroids Near Neptune Reveal a Solar System Conundrum

Posted by in categories: evolution, space

Unexplained patterns in the colors of certain space rocks suggest scientists still have much to learn about the solar system’s origins and early evolution.

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Nov 19, 2018

Coming to terms with complexity: Eco-evolutionary dynamics under more than one selection pressure

Posted by in categories: biotech/medical, evolution, genetics

We found that the evolution of anti-predatory defense in the prey species stabilized predator population size but that this was delayed in the presence of the abiotic stressor. This corresponded with a lack or delay in the evolution of resistance to the abiotic stressor. Therefore, the abiotic stressor had a big effect on the eco-evolutionary dynamics, weakening the evo-to-eco link. One might expect that this is caused by competition between (asexual) bacterial lineages possessing different adaptations, decreasing the rate and directionality of evolution under multiple selection pressures. Instead, the genomic investigation showed that different targets (genes or duplicated sites) were repeatedly mutated in the individual and combined treatments. The population genetics thus revealed complex mechanistic underpinnings for a seemingly sensible difference in dynamics. Perhaps a specific type of bacterial cell clumping or another adaptation is favored in the dual-stressor environment because of conferring a degree of resistance to both types of stressors? This could then direct the mutational path away from the optimal adaptations to the individual stressors.

It took us five years to disentangle the complex interplay between ecology and evolution in an experimental system consisting of bacteria, ciliates and antibiotics.

Go to the profile of Johannes Cairns

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