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Archive for the ‘evolution’ category: Page 123

Aug 13, 2018

Biomimetic micro/nanoscale fiber reinforced composites

Posted by in categories: biological, engineering, evolution, nanotechnology

Over hundreds of millions of years of evolution, nature has produced a myriad of biological materials that serve either as skeletons or as defensive or offensive weapons. Although these natural structural materials are derived from relatively sterile natural components, such as fragile minerals and ductile biopolymers, they often exhibit extraordinary mechanical properties due to their highly ordered hierarchical structures and sophisticated interfacial design. Therefore, they are always a research subject for scientists aiming to create advanced artificial structural materials.

Through microstructural observation, researchers have determined that many biological materials, including fish scales, crab claws and bone, all have a characteristic “twisted plywood” structure that consists of a highly ordered arrangement of micro/nanoscale fiber lamellas. They are structurally sophisticated natural fiber-reinforced composites and often exhibit excellent damage tolerance that is desirable for engineering structural materials, but difficult to obtain. Therefore, researchers are seeking to mimic this kind of natural hierarchical structure and interfacial design by using artificial synthetic and abundant one-dimensional micro/nanoscale fibers as building blocks. In this way, they hope to produce high-performance artificial structural materials superior to existing materials.

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Aug 10, 2018

Scientists take a closer look at Earth’s first animals

Posted by in category: evolution

When did animals originate? In research published in the journal Palaeontology, we show that this question is answered by Cambrian period fossils of a frond-like sea creature called Stromatoveris psygmoglena.

The Ediacaran Period lasted from 635 to 542m years ago. This era is key to understanding animal origins because it occurred just before the “Cambrian explosion” of 541m years ago, when many of the animal groups living today first appeared in the fossil record.

Yet when large fossils from the Ediacaran Period were first identified during the 20th century they included unique frond-like forms, which were not quite like any living animal. This prompted one of the greatest debates still raging in evolution. What exactly were these enigmatic fossils, often called the Ediacaran biota?

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Aug 10, 2018

Risks for Life on Habitable Planets from Superflares of Their Host Stars

Posted by in categories: alien life, economics, evolution, existential risks

We explore some of the ramifications arising from superflares on the evolutionary history of Earth, other planets in the solar system, and exoplanets. We propose that the most powerful superflares can serve as plausible drivers of extinction events, and that their periodicity corresponds to certain patterns in the terrestrial fossil diversity record. On the other hand, weaker superflares may play a positive role in enabling the origin of life through the formation of key organic compounds. Superflares could also prove to be quite detrimental to the evolution of complex life on present-day Mars and exoplanets in the habitable zone of M- and K-dwarfs. We conclude that the risk posed by superflares has not been sufficiently appreciated, and that humanity might potentially witness a superflare event in the next $\sim {10}^{3}$ years, leading to devastating economic and technological losses. In light of the many uncertainties and assumptions associated with our analysis, we recommend that these results should be viewed with due caution.

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Aug 4, 2018

Scale-invariant magnetoresistance in a cuprate superconductor

Posted by in categories: evolution, law, quantum physics

Cuprate superconductors have many unusual properties even in the “normal” (nonsuperconducting) regions of their phase diagram. In the so-called “strange metal” phase, these materials have resistivity that scales linearly with temperature, in contrast to the usual quadratic dependence of ordinary metals. Giraldo-Gallo et al. now find that at very high magnetic fields—up to 80 tesla—the resistivity of the thin films of a lanthanum-based cuprate scales linearly with magnetic field as well, again in contrast to the expected quadratic law. This dual linear dependence presents a challenge for theories of the normal state of the cuprates.

Science, this issue p. 479

The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La2–xSrxCuO4 cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.

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Jul 22, 2018

An Introduction to the Future with Oxford VSI

Posted by in categories: climatology, education, evolution, existential risks, futurism, general relativity, homo sapiens, philosophy, transhumanism

“The Future: A Very Short Introduction” (OUP, 2017) by Dr. Jennifer M Gidley.


Oxford University Press has just released a wonderful little animation video centring on my book “The Future: A Very Short Introduction” published in 2017. In an entertaining way it shows how the concept of the future or futures is central to so many other concepts — many of which are the subject of other OUP Very Short Introductions. The VSI Series now has well over 500 titles, with ‘The Future’ being number 516.

To watch the video click here.

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Jul 19, 2018

Glowing bacteria on deep-sea fish shed light on evolution, ‘third type’ of symbiosis

Posted by in categories: biotech/medical, evolution

You may recognize the anglerfish from its dramatic appearance in the hit animated film Finding Nemo, as it was very nearly the demise of clownfish Marlin and blue-tang fish Dory. It lives most of its life in total darkness more than 1,000 meters below the ocean surface. Female anglerfish sport a glowing lure on top of their foreheads, basically a pole with a light bulb on its end, where bioluminescent bacteria live. The light-emitting lure attracts both prey and potential mates to the fish.

Despite its recent fame, little is known about anglerfish and their symbiotic relationship with these brilliant , because the fish are difficult to acquire and study.

For the first time, scientists have sequenced and analyzed the genomes of bacteria that live in anglerfish bulbs. The bacteria were taken from fish specimens collected in the Gulf of Mexico.

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Jul 10, 2018

Two Papers Trace The Steps Leading From Moles to Melanomas

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

Researchers isolated several mutations leading to melanoma and reproduced them in the lab using CRISPR.


Two papers authored by researchers at the University of California, San Francisco described the genetic changes that turn harmless moles into malignant melanomas and the experiment they devised to recreate the step-by-step evolution of normal skin cells into cancer cells [1], [2].

Summary ([1])

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Jul 7, 2018

What will humans look like in a million years?

Posted by in categories: biological, cyborgs, evolution

To understand our future evolution we need to look to our past.

Will our descendants be cyborgs with hi-tech machine implants, regrowable limbs and cameras for eyes like something out of a science fiction novel?

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Jul 5, 2018

Mystery of Charles Darwin’s flying spiders solved — they harness electricity

Posted by in category: evolution

You might assume that evolution gave Charles Darwin enough to ponder during his five year voyage on The Beagle.

But of all the phenomena the naturalist encountered circumnavigating the globe, it was the flight of spiders which continued to puzzle him.

Darwin noticed that hundreds of spiders would inexplicably land on the Beagle even on a calm day without any wind to blow them on board.

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Jul 4, 2018

Asia’s mysterious role in the early origins of humanity

Posted by in categories: biotech/medical, evolution

Bizarre fossils from China are revealing our species’ Asian origins and rewriting the story of human evolution.

By Kate Douglas

DECEMBER 1941. Japan has just entered the second world war. China, already fighting its neighbour, is in the firing line. At the Peking Union Medical College Hospital, Hu Chengzhi carefully packs two wooden crates with the world’s most precious anthropological artefacts. Peking Man – in reality some 200 fossilised teeth and bones, including six skulls – is to be shipped to the US for safekeeping. This is the last anyone ever sees of him.

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