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Archive for the ‘evolution’ category: Page 104

Jul 2, 2020

There was a crooked man: Scoliosis and the deep history of the brain’s inner sanctum

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

Lurking just beneath the surface of just about every common nursery rhyme is a complex record of times long gone. For example, the “crooked man” who “laid a crooked sixpence upon a crooked style” was none other than the great 17th-century Scot General Sir Alexander Leslie. The crooked stile was the uneasy border between Scotland and England established by the controversial covenant he signed. Quite similarly, many enigmatic structures that permanently persist or otherwise transiently appear and resorb in the development of the nervous systems of many creatures also encode a rich evolutionary past.

One such functioning relic is Reissner’s fiber, a glycoprotein sheet secreted by the subcommissural organ (SCO) that inexorably treadmills down the central canal of the spinal cord. Although the SCO was one of the first structures of the mammalian brain to differentiate, in humans, it begins regressing around age three or four and typically becomes vestigial by adulthood. The main component of Reissner’s fiber is a giant 5000-amino-acid vertebrate molecule called SCO-spondin. This protein contains axonal pathfinding domains critical to development of the posterior commissure, a transhemispheric highway that bears axons controlling the pupillary light reflex.

The other product of the SCO is a thyroid-hormone-transporting protein called transthyretin. Much like all the organified metals fixed by life, iodine has a unique story to tell in the evolution of the body plan. Recently, an intriguing connection between Reissner’s fiber and development of the spine that houses it has been discovered in the model organism, zebrafish. These fish, as recently observed for the serotonergic control of neurogenesis, have proven to be an exemplary model for studying all things neural. In the latest issue of Current Biology, author Nathalie Jurisch-Yaksi reviews a remarkable confluence of ideas that establish an indisputable role for Reissner’s membrane building a straight and strong spine.

Jun 29, 2020

Nanotechnology applied to medicine: The first liquid retina prosthesis

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

Research at IIT-Istituto Italiano di Tecnologia (Italian Institute of Technology) has led to the revolutionary development of an artificial liquid retinal prosthesis to counteract the effects of diseases such as retinitis pigmentosa and age-related macular degeneration that cause the progressive degeneration of photoreceptors of the retina, resulting in blindness. The study has been published in Nature Nanotechnology.

The study represents the state of the art in retinal prosthetics and is an evolution of the planar artificial retinal model developed by the same team in 2017 and based on organic semiconductor materials (Nature Materials 2017, 16: 681–689).

The ‘second generation’ artificial retina is biomimetic, offers and consists of an aqueous component in which photoactive polymeric nanoparticles (whose size is 350 nanometres, thus about 1/100 of the diameter of a hair) are suspended, and will replace damaged photoreceptors.

Jun 27, 2020

Mapping the Early Universe with NASA’s Webb Telescope

Posted by in categories: cosmology, evolution, mapping

Although many other observatories, including NASA’s Hubble Space Telescope, have previously created “deep fields” by staring at small areas of the sky for significant chunks of time, the Cosmic Evolution Early Release Science (CEERS) Survey, led by Steven L. Finkelstein of the University of Texas at Austin, will be one of the first for Webb. He and his research team will spend just over 60 hours pointing the telescope at a slice of the sky known as the Extended Groth Strip, which was observed as part of Hubble’s Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey or CANDELS.

“With Webb, we want to do the first reconnaissance for galaxies even closer to the big bang,” Finkelstein said. “It is absolutely not possible to do this research with any other telescope. Webb is able to do remarkable things at wavelengths that have been difficult to observe in the past, on the ground or in space.”

Mark Dickinson of the National Science Foundation’s National Optical-Infrared Astronomy Research Laboratory in Arizona, and one of the CEERS Survey co-investigators, gives a nod to Hubble while also looking forward to Webb’s observations. “Surveys like the Hubble Deep Field have allowed us to map the history of cosmic star formation in galaxies within a half a billion years of the big bang all the way to the present in surprising detail,” he said. “With CEERS, Webb will look even farther to add new data to those surveys.”

Jun 26, 2020

Podcasts to Listen To: Future Thinkers and the best futurist podcasts to listen to

Posted by in categories: evolution, neuroscience

Nobody can predict what will happen in the future, but there are a few who are trying to help make sense of what is coming. Known as futurists, these “future” experts study the future and make predictions based on current trends. Here are a few futurist podcasts to help you make sense of where we are headed.

Future Thinkers

Created by Mike Gilliland and Euvie Ivanova, this podcast is focused on the evolution of society, technology and consciousness. Episodes include interviews with company founders, psychologists and philosophers. Recent episodes include “James Ehrlich — Regenerative Villages,” “Donald Hoffman — Do We See Reality As It Is?” and “Jamie Wheal Q&A.”

Jun 26, 2020

New study reveals how metamorphosis has shaped the evolution of salamanders

Posted by in categories: education, evolution

A team of scientists, led by Natural History Museum postdoctoral researcher Dr. Anne-Claire Fabre, have conducted the first study on how metamorphosis has influenced the evolution of salamanders.

Using micro-CT scanning to study the skulls of this group of animals, the team were able to build a huge dataset of 148 species of and used cutting-edge methods to describe the shape of the with nearly 1000 reference points, known as landmarks.

Dr. Fabre said, “Most studies of this kind are limited to just a few dozen landmarks. Our study is the first large-scale investigation of this incredibly diverse group. We have captured the shape of the skull in such great detail that it has allowed us to learn more than ever before about how these creatures evolved.”

Jun 25, 2020

From Jekyll to Hyde: Genetic Mutation That Makes E. Coli Deadlier Pinpointed

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

Scientists identify an important protein that increases “bacterial virulence,” when mutated, changing harmless bacteria to harmful ones.

As far as humans are concerned, bacteria can be classified as either harmful, pathogenic bacteria and harmless or beneficial non-pathogenic bacteria. To develop better treatments for diseases caused by pathogenic bacteria, we need to have a good grasp on the mechanisms that cause some bacteria to be virulent. Scientists have identified genes that cause virulence, or capability to cause disease, but they do not fully know how bacteria evolve to become pathogenic.

To find out, Professor Chikara Kaito and his team of scientists from Okayama University, Japan, used a process called experimental evolution to identify molecular mechanisms that cells develop to gain useful traits, and published their findings in PLoS Pathogens. “We’re excited by this research because no one has ever looked at virulence evolution of bacteria in an animal; studies before us looked at the evolution in cells,” said Prof Kaito.

Jun 21, 2020

Lost 8 Billion Light Years of Universe Evolution Revealed by Gravitational Waves

Posted by in categories: cosmology, evolution, physics

Every year, 2 million black hole mergers are missed — Australian scientists work out how to detect them, revealing a lost 8 billion light-years of Universe evolution.

Last year, the Advanced LIGO –VIRGO gravitational-wave detector network recorded data from 35 merging black holes and neutron stars. A great result — but what did they miss? According to Dr. Rory Smith from the ARC Centre of Excellence in Gravitational Wave Discovery at Monash University in Australia — it’s likely there are another 2 million gravitational wave events from merging black holes, “a pair of merging black holes every 200 seconds and a pair of merging neutron stars every 15 seconds” that scientists are not picking up.

Dr. Smith and his colleagues, also at Monash University, have developed a method to detect the presence of these weak or “background” events that to date have gone unnoticed, without having to detect each one individually. The method — which is currently being test driven by the LIGO community — “means that we may be able to look more than 8 billion light-years further than we are currently observing,” Dr. Smith said.

Jun 19, 2020

Human brain size gene triggers bigger brain in monkeys

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

The expansion of the human brain during evolution, specifically of the neocortex, is linked to cognitive abilities such as reasoning and language. A certain gene called ARHGAP11B that is only found in humans triggers brain stem cells to form more stem cells, a prerequisite for a bigger brain. Past studies have shown that ARHGAP11B, when expressed in mice and ferrets to unphysiologically high levels, causes an expanded neocortex, but its relevance for primate evolution has been unclear.

Researchers at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) in Dresden, together with colleagues at the Central Institute for Experimental Animals (CIEA) in Kawasaki and the Keio University in Tokyo, both located in Japan, now show that this human-specific gene, when expressed to physiological levels, causes an enlarged in the common marmoset, a New World monkey. This suggests that the ARHGAP11B gene may have caused neocortex expansion during human evolution. The researchers published their findings in the journal Science.

The human neocortex, the evolutionarily youngest part of the cerebral cortex, is about three times bigger than that of the closest human relatives, chimpanzees, and its folding into wrinkles increased during evolution to fit inside the restricted space of the skull. A key question for scientists is how the human neocortex became so big. In a 2015 study, the research group of Wieland Huttner, a founding director of the MPI-CBG, found that under the influence of the human-specific gene ARHGAP11B, mouse embryos produced many more neural progenitor cells and could even undergo folding of their normally unfolded neocortex. The results suggested that the gene ARHGAP11B plays a key role in the evolutionary expansion of the human neocortex.

Jun 18, 2020

Scientists reveal a lost eight billion light years of universe evolution

Posted by in categories: cosmology, evolution, physics

Last year, the Advanced LIGO-VIRGO gravitational-wave detector network recorded data from 35 merging black holes and neutron stars. A great result—but what did they miss? According to Dr. Rory Smith from the ARC Centre of Excellence in Gravitational Wave Discovery at Monash University in Australia—it’s likely there are another 2 million gravitational wave events from merging black holes, “a pair of merging black holes every 200 seconds and a pair of merging neutron stars every 15 seconds” that scientists are not picking up.

Dr. Smith and his colleagues, also at Monash University, have developed a method to detect the presence of these weak or “background” events that to date have gone unnoticed, without having to detect each one individually. The method—which is currently being test driven by the LIGO community—” means that we may be able to look more than 8 billion further than we are currently observing,” Dr. Smith said.

“This will give us a snapshot of what the looked like while providing insights into the evolution of the .”

Jun 17, 2020

There Are At Least 36 Intelligent Alien Civilizations In Our Galaxy, Say Scientists

Posted by in categories: alien life, evolution

A new cosmic evolution-based calculation that say that there are likely to be more than 36 ongoing intelligent civilizations throughout our Milky Way galaxy.