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Archive for the ‘evolution’ category: Page 109

Mar 19, 2020

Astronomers determine chemical composition of a nearby stellar stream

Posted by in categories: evolution, space

Stellar streams are long, thin filaments of orbiting galaxies, produced by the stretching action of tidal forces. For astronomers, observation of these structures could be crucial to test various galaxy formation models.

Located most likely some 420 light-years away in the Milky Way’s disk, Pisces–Eridanus (or Psc–Eri for short) is a cylindrically shaped stream of almost 1,400 identified stars distributed across about 2,300 light-years. Due to its relative proximity and , it is perceived as an excellent laboratory to study and test theories of chemical and dynamical evolution of stellar systems.

Mar 18, 2020

Ancient fish fossil reveals evolutionary origin of the human hand

Posted by in categories: evolution, habitats

An ancient Elpistostege fish fossil found in Miguasha, Canada has revealed new insights into how the human hand evolved from fish fins.

An international team of palaeontologists from Flinders University in Australia and Universite du Quebec a Rimouski in Canada have revealed the specimen, as described in the journal Nature, has yielded the missing evolutionary link in the fish to tetrapod transition, as fish began to foray in habitats such as and land during the Late Devonian period millions of years ago.

This complete 1.57 metre long fish shows the complete arm (pectoral fin) skeleton for the first time in any elpistostegalian fish. Using high energy CT-scans, the skeleton of the pectoral fin revealed the presence of a humerus (arm), radius and ulna (forearm), rows of carpus (wrist) and phalanges organized in digits (fingers).

Mar 16, 2020

Scientists have discovered the origins of the building blocks of life

Posted by in categories: alien life, evolution

:oooooo.


Rutgers researchers have discovered the origins of the protein structures responsible for metabolism: simple molecules that powered early life on Earth and serve as chemical signals that NASA could use to search for life on other planets.

Their study, which predicts what the earliest proteins looked like 3.5 billion to 2.5 billion years ago, is published in the journal Proceedings of the National Academy of Sciences.

Continue reading “Scientists have discovered the origins of the building blocks of life” »

Mar 13, 2020

Slime Mold Simulations Map Dark Matter Holding Universe Together

Posted by in categories: biological, cosmology, evolution

The behavior of one of nature’s humblest creatures is helping astronomers probe the largest structures in the universe.

The single-cell organism, known as slime mold (Physarum polycephalum), builds complex filamentary networks in search of food, finding near-optimal pathways to connect different locations. In shaping the universe, gravity builds a vast cobweb structure of filaments tying galaxies and clusters of galaxies together along faint bridges hundreds of millions of light-years long. There is an uncanny resemblance between the two networks: one crafted by biological evolution, and the other by the primordial force of gravity.

The cosmic web is the large-scale backbone of the cosmos, consisting primarily of the mysterious substance known as dark matter and laced with gas, upon which galaxies are built. Dark matter cannot be seen, but it makes up the bulk of the universe’s material. The existence of a web-like structure to the universe was first hinted at in the 1985 Redshift Survey conducted at the Harvard-Smithsonian Center for Astrophysics. Since those studies, the grand scale of this filamentary structure has grown in subsequent sky surveys. The filaments form the boundaries between large voids in the universe.

Mar 9, 2020

CRISPR Pill May Be Key in Fight Against Antibiotic Resistance

Posted by in categories: biotech/medical, evolution

Even since Alexander Fleming stumbled across penicillin—the first antibiotic drug—scientists knew our fight with evolution was on.

Most antibiotics work by blocking biological processes that allow bacteria to thrive and multiply. With prolonged, low-dosage use, however, antibiotics become a source of pressure that forces bacteria to evolve—and because these microorganisms are extremely adept at swapping and sharing bits of their DNA, when one member becomes resistant, so does most of its population.

Continue reading “CRISPR Pill May Be Key in Fight Against Antibiotic Resistance” »

Mar 8, 2020

Chiral Higgs Mode in Nematic Superconductors

Posted by in categories: energy, evolution

Nematic superconductivity with spontaneously broken rotation symmetry has recently been reported in doped topological insulators, M x Bi 2 Se 3 (M = Cu, Sr, Nb). Here we show that the electromagnetic (EM) response of these compounds provides a spectroscopy for bosonic excitations that reflect the pairing channel and the broken symmetries of the ground state. Using quasiclassical Keldysh theory, we find two characteristic bosonic modes in nematic superconductors: the nematicity mode and the chiral Higgs mode. The former corresponds to the vibrations of the nematic order parameter associated with broken crystal symmetry, while the latter represents the excitation of chiral Cooper pairs. The chiral Higgs mode softens at a critical doping, signaling a dynamical instability of the nematic state towards a new chiral ground state with broken time reversal and mirror symmetry. Evolution of the bosonic spectrum is directly captured by EM power absorption spectra. We also discuss contributions to the bosonic spectrum from subdominant pairing channels to the EM response.

Mar 7, 2020

Scientists discover strong evidence of life on Mars

Posted by in categories: alien life, evolution

We’ve been expecting aliens from Mars for decades now, but what if life was vanquished on the red planet before evolution ever got the chance to take hold?

A pair of researchers recently published an analysis of 3.5 billion-years-old soil samples from Mars containing chemical compounds called “thiophenes” that could, potentially, be organic. If they are, it would be highly likely that bacteria once lived on the planet.

Terrestrial thiophenes are considered tell-tale signs of life by Earthbound biologists. The presence of these possibly-organic compounds in Martian soil represents the strongest evidence yet that life may have once existed anywhere other than Earth.

Mar 6, 2020

Rats avoid harming other rats. The finding may help us understand sociopaths

Posted by in categories: evolution, neuroscience

Humans and rodents have similar brain structures that regulate empathy, suggesting the behavior is deeply rooted in mammal evolution.

Mar 5, 2020

Our Genetic Future Is Coming… Faster Than We Think

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

If there was a public vote about human gene enhancement, would you vote YES or NO?


Our species is on the cusp of a revolution that will change every aspect of our lives but we’re hardly talking about it.

Continue reading “Our Genetic Future Is Coming… Faster Than We Think” »

Mar 4, 2020

New insights into evolution: Why genes appear to move around

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

Scientists at Uppsala University have proposed an addition to the theory of evolution that can explain how and why genes move on chromosomes. The hypothesis, called the SNAP Hypothesis, is presented in the scientific journal PLOS Genet ics.

Life originated on Earth almost 4 billion years ago and diversified into a vast array of species. How did this diversification occur? The Theory of Evolution, together with the discovery of DNA and how it replicates, provide an answer and a mechanism. Mutations in DNA occur from generation to generation, and can be selected if they help individuals to adapt better to their environment. Over time, this has led to the separation of organisms into the different species that now inhabit all ecosystems.

Current theory holds that evolution involves mistakes made when replicating a gene. This explains how genes can mutate over time and acquire new functions. However, a mystery in biology is that the relative locations of genes on also change over time. This is obvious in bacteria, as different species often have the same genes in very different relative locations. Since the , genes have apparently been changing location. The questions are, how and why do genes move their relative locations?