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Archive for the ‘evolution’ category: Page 113

Nov 18, 2019

The measurements of the expansion of the universe don’t add up

Posted by in categories: cosmology, evolution, physics

Physicists use two types of measurements to calculate the expansion rate of the universe, but their results do not coincide, which may make it necessary to update the cosmological model. “It’s like trying to thread a cosmic needle,” explains researcher Licia Verde of the University of Barcelona, co-author of an article on the implications of this problem.

More than a hundred scientists met this summer at the Kavli Institute for Theoretical Physics at the University of California (U.S.) to try to clarify what is happening with the discordant data on the expansion rate of the , an issue that affects the very origin, evolution and fate of our cosmos. Their conclusions have been published in Nature Astronomy journal.

“The problem lies in the Hubble constant (H0), a parameter which value—it is actually not a constant because it changes with time—indicates how fast the Universe is currently expanding,” points out cosmologist Licia Verde, an ICREA researcher at the Institute of Cosmos Sciences of the University of Barcelona (ICC-UB) and the main author of the article.

Nov 18, 2019

Life-long epigenetic programming of cortical architecture

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

The evolution of human diets led to preferences toward polyunsaturated fatty acid (PUFA) content with ‘Western’ diets enriched in ω-6 PUFAs. Mounting evidence points to ω-6 PUFA excess limiting metabolic and cognitive processes that define longevity in humans. When chosen during pregnancy, ω-6 PUFA-enriched ‘Western’ diets can reprogram maternal bodily metabolism with maternal nutrient supply precipitating the body-wide imprinting of molecular and cellular adaptations at the level of long-range intercellular signaling networks in the unborn fetus. Even though unfavorable neurological outcomes are amongst the most common complications of intrauterine ω-6 PUFA excess, cellular underpinnings of life-long modifications to brain architecture remain unknown. Here, we show that nutritional ω-6 PUFA-derived endocannabinoids desensitize CB1 cannabinoid receptors, thus inducing epigenetic repression of transcriptional regulatory networks controlling neuronal differentiation. We found that cortical neurons lose their positional identity and axonal selectivity when mouse fetuses are exposed to excess ω-6 PUFAs in utero. Conversion of ω-6 PUFAs into endocannabinoids disrupted the temporal precision of signaling at neuronal CB1 cannabinoid receptors, chiefly deregulating Stat3-dependent transcriptional cascades otherwise required to execute neuronal differentiation programs. Global proteomics identified the immunoglobulin family of cell adhesion molecules (IgCAMs) as direct substrates, with DNA methylation and chromatin accessibility profiling uncovering epigenetic reprogramming at 1400 sites in neurons after prolonged cannabinoid exposure. We found anxiety and depression-like behavioral traits to manifest in adult offspring, which is consistent with genetic models of reduced IgCAM expression, to suggest causality for cortical wiring defects. Overall, our data uncover a regulatory mechanism whose disruption by maternal food choices could limit an offspring’s brain function for life.


  • Immediate Communication
  • Published: 18 November 2019
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Nov 14, 2019

How human brain development diverged from great apes

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

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Institute of Molecular and Clinical Ophthalmology Basel, and ETH Zurich, Switzerland, have presented new insights into the development of the human brain and differences in this process compared to other great apes. The study reveals features of brain development that are unique to humans, and outlines how these processes have diverged from those in other primates.

Since humans diverged from a common ancestor shared with chimpanzees and the other great apes, the has changed dramatically. However, the genetic and developmental processes responsible for this divergence are not understood. Cerebral organoids (brain-like tissues), grown from stem cells in a dish, offer the possibility to study the evolution of early brain development in the laboratory.

Sabina Kanton, Michael James Boyle and Zhisong He, co-first authors of the study, together with Gray Camp, Barbara Treutlein and colleagues analyzed human through their development from to explore the dynamics of gene expression and regulation using methods called single-cell RNA-seq and ATAC-seq. The authors also examined chimpanzee and macaque cerebral organoids to understand how organoid development differs in humans.

Nov 14, 2019

Museums put ancient DNA to work for wildlife

Posted by in categories: biotech/medical, education, evolution, existential risks, genetics

Scientists who are trying to save species at the brink of extinction are finding help in an unexpected place.

Heather Farrington, curator of zoology for the Cincinnati Museum Center, is using DNA from specimens collected more than 100 years ago to help understand the evolution and stresses faced by today’s animals.

Farrington runs the museum’s new state-of-the-art genetics laboratory, which helps researchers study populations of animals over time.

Nov 13, 2019

Evolution can reconfigure gene networks to deal with environmental change

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

Scientists at the University of Birmingham have unravelled the genetic mechanisms behind tiny waterfleas’ ability to adapt to increased levels of phosphorus pollution in lakes.

By mapping networks of to the physiological responses of ancient and modern waterfleas (Daphnia), the researchers, based in the University’s School of Biosciences, were able to show that a cluster of over 800 genes, many of them involved in , evolved to become “plastic”, or flexible.

This allows the modern Daphnia to adjust its gene expression according to the amount of phosphorus present in the environment. This is particularly fascinating as their 700-year-old ancestors were incapable of such a plastic response.

Nov 8, 2019

Scientists further refine how quickly the universe is expanding

Posted by in categories: cosmology, evolution

Wielding state-of-the-art technologies and techniques, a team of Clemson University astrophysicists has added a novel approach to quantifying one of the most fundamental laws of the universe.

In a paper published Friday, Nov. 8, in The Astrophysical Journal, Clemson scientists Marco Ajello, Abhishek Desai, Lea Marcotulli and Dieter Hartmann have collaborated with six other scientists around the world to devise a new measurement of the Hubble Constant, the unit of measure used to describe the rate of expansion of the .

“Cosmology is about understanding the evolution of our universe—how it evolved in the past, what it is doing now and what will happen in the future,” said Ajello, an associate professor in the College of Science’s department of physics and astronomy. “Our knowledge rests on a number of parameters—including the Hubble Constant—that we strive to measure as precisely as possible. In this paper, our team analyzed data obtained from both orbiting and ground-based telescopes to come up with one of the newest measurements yet of how quickly the universe is expanding.”

Oct 31, 2019

In the long run, mutation is the key to evolution, but in the short run, it’s not exactly your health’s best friend

Posted by in categories: evolution, life extension

Here’s how genomic instability messes with your body and contributes to aging.

Oct 30, 2019

The Case Against Reality, a new book

Posted by in categories: evolution, neuroscience

After reading the new book “The Case Against Reality: Why evolution hid the truth from our eyes” by cognitive scientist Donald D. Hoffman, many academics and general readers alike may conclude that the Interface Theory of Perception well might be regarded as the most advanced theory of consciousness to date. If you dare to glance outside the paradigmatic square of neuroscience and neurophilosophy, then this book opens up a brand new perspective shedding light on the most probable future venue of scientific endeavor for the theory of everything with computational underpinnings and revolving around phenomenal consciousness.


Challenging the orthodoxy of still-predominant physicalism with undeniable logic and recent epistemological discoveries, Donald Hoffman crafts out his new Interface Theory of Perception which, for some inexplicable reason has been overlooked for so long and is but self-evident: Each conscious agent inhabits their own virtual bubble-universe while using species-specific sensory-cognitive modality in interfacing with objective reality.

In my recently-published book The Syntellect Hypothesis: Five Paradigms of the Mind’s Evolution (2019) I go a step further by submitting to you that “that something in objective reality” (in the words of Hoffman) is nothing less than non-local consciousness, or the Universal Mind if you prefer, co-creating each and every observer timeline. My ‘Experiential Realism’ is Hoffman’s Conscious Realism.

Continue reading “The Case Against Reality, a new book” »

Oct 24, 2019

Fossil Trove Offers Clues to How Life Found a Way After Asteroid That Wiped Out Dinosaurs

Posted by in categories: asteroid/comet impacts, evolution, existential risks

On the outskirts of Colorado Springs, researchers have uncovered thousands of fossils showing how life on Earth revived in the aftermath of an asteroid impact 66 million years or so ago that killed most dinosaurs and other life on land and sea.

Taken together, the fossil trove documents an era when evolution, in essence, hit the reset button. While countless species vanished forever, some plants and animals rebounded relatively quickly in the first million years after the devastation, including the mammals ancestral to humankind, the scientists said in research published Thursday in Science.

Oct 22, 2019

Humans May Be the Only Intelligent Life in the Universe, If Evolution Has Anything to Say

Posted by in categories: alien life, evolution

Could intelligence simply be unlikely to evolve? Unfortunately, we can’t study extraterrestrial life to answer this question. But we can study some 4.5 billion years of Earth’s history, looking at where evolution repeats itself, or doesn’t.

Related: from big bang to present: snapshots of our universe through time.