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Archive for the ‘evolution’ category: Page 113

Sep 18, 2019

Guppies teach us why evolution happens

Posted by in categories: evolution, genetics

Guppies, a perennial pet store favorite, have helped a UC Riverside scientist unlock a key question about evolution:

Do animals evolve in response to the risk of being eaten, or to the environment that they create in the absence of predators? Turns out, it’s the latter.

David Reznick, a professor of biology at UC Riverside, explained that in the wild, guppies can migrate over waterfalls and rapids to places where most predators can’t follow them. Once they arrive in safer terrain, Reznick’s previous research shows they evolve rapidly, becoming genetically distinct from their ancestors.

Sep 17, 2019

Rare 10 million-year-old fossil unearths new view of human evolution

Posted by in category: evolution

Near an old mining town in Central Europe, known for its picturesque turquoise-blue quarry water, lay Rudapithecus. For 10 million years, the fossilized ape waited in Rudabánya, Hungary, to add its story to the origins of how humans evolved.

What Rudabánya yielded was a pelvis—among the most informative bones of a skeleton, but one that is rarely preserved. An international research team led by Carol Ward at the University of Missouri analyzed this new pelvis and discovered that bipedalism—or the ability for people to move on two legs—might possibly have deeper ancestral origins than previously thought.

The Rudapithecus pelvis was discovered by David Begun, a professor of anthropology at the University of Toronto who invited Ward to collaborate with him to study this fossil. Begun’s work on limb bones, jaws and teeth has shown that Rudapithecus was a relative of modern African apes and humans, a surprise given its location in Europe. But information on its posture and locomotion has been limited, so the discovery of a pelvis is important.

Sep 12, 2019

Dietary supplement may help with schizophrenia

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

A dietary supplement, sarcosine, may help with schizophrenia as part of a holistic approach complementing antipsychotic medication, according to a UCL researcher.

In an editorial published in the British Journal of Psychiatry, Professor David Curtis (UCL Genetics, Evolution & Environment and QMUL Centre for Psychiatry) suggests the readily available product could easily be incorporated into treatment plans, while calling for clinical trials to clarify the benefit and inform guidelines.

“Sarcosine represents a very logical treatment and the small number of so far do seem to show that it can be helpful. It certainly seems to be safe and some patients report feeling better on it,” he said.

Sep 10, 2019

Chicken study reveals that environmental factors, not just chance, could drive species evolution

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

In the version of evolutionary theory most of us are familiar with, randomly occurring variation in traits, caused by mutations in our DNA, can be fixed in a population through natural selection. However, writing in Epigenetics journal, a team of Swedish researchers from Linköping University suggests that mutations that can be caused by environmental changes, not just random chance, might be responsible for species diversity.

Until quite recently, it was assumed that DNA causing new gene variations occurred more or less randomly. While random mutations do occur, recent research has shown that can be altered by environmental influences too. According to a study published in Epigenetics journal, a particular type of mutation, linked to , has, over time, led to new animal breeds—and could be responsible for whole new species.

Sep 8, 2019

The skull of humanity’s oldest known ancestor is changing our understanding of evolution

Posted by in category: evolution

The recent discovery of a 3.8m-year-old cranium (skull without the lower jaw) is the hottest topic of conversation among palaeoanthropologists right now. But fossils are found all the time, so why is the cranium of this small, old man so important? It turns out the discovery is changing our view of how early hominin species evolved – and how they led to humans. To understand how, let’s start at the beginning.

In 1995, researchers found several partial jaws, isolated teeth and limb bones in Kenya, dated between 4.2m and 3.9m years old, and assigned them to a brand new species: Australopithecus anamensis. All these fossils were found in sediments associated with an ancient lake – “anam”, which means lake in the local language. A number of additional specimens were then found in Ethiopia, thought to belong to the same species.

The primitive features of A. anamensis have led to the widespread view that this species is the ancestor of Australopithecus afarensis, a younger hominin from Tanzania, Ethiopia and perhaps Kenya, dated between 3.8m and 3m years old. The most iconic fossil of A. afarensis is probably the partial skeleton known as Lucy, which was for a long time viewed as the oldest known human ancestor.

Sep 3, 2019

Undercover evolution: Our individuality is encrypted in our DNA, but it is deeper than expected

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

Providing a glimpse the hidden workings of evolution, a group of researchers at UC Santa Barbara have discovered that embryos that appear the same can start out with surprisingly different instructions.

“We found that a lot of undercover evolution occurs in ,” said Joel Rothman, a professor in the Department of Molecular, Cellular, and Developmental Biology, who led the team.

Indeed, although members of the same species are identical across the vast majority of their genomes, including all the genetic instructions used in development, Rothman and his colleagues found that key parts of the assembly instructions used when embryos first start developing can differ dramatically between individuals of the same species.

Sep 2, 2019

Quantum Darwinism spotted in diamond spins

Posted by in categories: evolution, quantum physics

A handful of spins in diamond have shone new light on one of the most enduring mysteries in physics – how the objective reality of classical physics emerges from the murky, probabilistic quantum world. Physicists in Germany and the US have used nitrogen-vacancy (NV) centres in diamond to demonstrate “quantum Darwinism”, whereby the “fittest” states of a system survive and proliferate in the transition between the quantum and classical worlds.

In the past, physicists tended to view the classical and quantum worlds as being divided by an abrupt barrier that makes a fundamental distinction between the familiar macroscopic (classical) and the unfamiliar microscopic (quantum) realms. But in recent decades that view has changed. Many experts now think that the transition is gradual, and that the definite classical states we measure come from probabilistic quantum states progressively (although very quickly) losing their coherence as they become ever more entangled with their environment.

Quantum Darwinism, put forward by Wojciech Zurek of Los Alamos National Laboratory in New Mexico, argues that the classical states we perceive are robust quantum states that can survive entanglement during decoherence. His theoretical framework posits that the information about these states will be duplicated many times and disseminated throughout the environment. Just as natural selection tells us that the fittest individuals in a species must survive to reproduce in great numbers and so go on to shape evolution, the fittest quantum states will be copied and appear classical. This redundancy means that many individual observers will measure any given state as having the same value, so ensuring objective reality.

Aug 29, 2019

Scientists See Human-Like Brain Waves in Lab-Grown Mini-Brains

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

One way that scientists can non-invasively study the human brain is by growing “mini-brains,” clusters of brain cells each about the size of a pea, in the lab. In a fascinating progression of this line of research, a team this week reports that they observed human-like brainwaves from these organoids.

Previous studies of mini-brains have demonstrated movement and nerve tract development, but the new study from researchers at the University of California San Diego, led by biologist Alysson Muotri, is the first to record human-like neural activity. In their paper, published in Cell Stem Cell on Thursday, the researchers write that they observed brain wave patterns resembling those of a developing human. This sophistication in the in vitro model is a step to enable scientists to use mini-brains to study brain development, model diseases, and learn about the evolution of brains, according to Muotri.

Aug 27, 2019

‘Antibiotic apocalypse’ New diseases and antibiotic resistance major threat to humanity

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

Dubbed ‘antibiotic apocalypse’, the antibiotic resistant superbugs have become a massive cause for concern for health professionals as their numbers continue to rise. Such is the worry around antibiotic superbugs that experts believe that they will claim 10 million lives by 2050, with 700,000 people dying a year after catching the infections, according to a recent report from the American Chemical Society’s Enviromental Science and Technology Journal. Humans, especially in the West, have become so reliant on antibiotics to help cure illnesses that many of the bacteria that they are trying to fight have become resistant to the drugs through evolution.

Aug 26, 2019

Simulation of eight million ‘mock universes’ sheds light on galaxy evolution

Posted by in categories: cosmology, evolution, physics

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