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Archive for the ‘evolution’ category: Page 75

Sep 29, 2021

Self-replicating protocells created in lab may be life’s “missing link”

Posted by in categories: biological, chemistry, evolution

A possible explanation for life from nonliving material.


Exactly how life first emerged from non-living matter is one of the most enduring mysteries of science. In a new study, Japanese scientists have created self-replicating protocells in the lab, which they say could represent the “missing link” between chemistry and biology.

Primitive Earth was covered with a sludgy mix of chemicals, containing organic molecules that formed the precursors for vital biological components like proteins and amino acids. There are several different hypotheses for how and where life sprang out of this soup, but one of the first ideas was known as chemical evolution, which is what the new study investigated.

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Sep 28, 2021

The nematode C. elegans senses airborne sound

Posted by in category: evolution

Hearing is thought to exist only in vertebrates and some arthropods, but not other animal phyla. Here, Xu and colleagues report that the earless nematode C. elegans senses airborne sound and engages in phonotaxis. Thus, hearing might have evolved multiple times independently in the animal kingdom, suggesting convergent evolution.

Sep 27, 2021

Dr Brian Keating, PhD — Into The Impossible — Chancellor’s Distinguished Professor of Physics — UCSD

Posted by in categories: cosmology, evolution, physics

Multiverse Cosmology, Nobel Laureates, Theories Of Everything, And Much More! — Dr. Brian Keating Ph.D., Chancellor’s Distinguished Professor of Physics, UC San Diego.


Dr. Brian Keating, Ph.D. (https://briankeating.com/) is Chancellor’s Distinguished Professor of Physics, at the Center for Astrophysics & Space Sciences (CASS), in the Department of Physics, at the University of California, San Diego (https://bkeating.physics.ucsd.edu/).

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Sep 26, 2021

Life-like cells are made of metal

Posted by in categories: biological, evolution, particle physics

Circa 2011 o,.o Foglet bodies around the corner sooner than we think 🤔


Could living things that evolved from metals be clunking about somewhere in the universe? Perhaps. In a lab in Glasgow, UK, one man is intent on proving that metal-based life is possible.

He has managed to build cell-like bubbles from giant metal-containing molecules and has given them some life-like properties. He now hopes to induce them to evolve into fully inorganic self-replicating entities.

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Sep 25, 2021

In a gene tied to growth, scientists see glimmers of human history

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

“Our study points to sex-and environment-specific effects of a common genetic variant. In the mice, we observed that Ghrd3 leads to a ‘female-like’ expression pattern of dozens of genes in male livers under calorie restriction, which potentially leads to the observed size reduction,” Saitou says.

“Females, already smaller in size, may suffer from negative evolutionary consequences if they lose body weight. Thus, it is a reasonable and also very interesting hypothesis that a genetic variant that may affect response to nutritional stress has evolved in a sex-specific manner,” Mu says.


A new study delves into the evolution and function of the human growth hormone receptor gene, and asks what forces in humanity’s past may have driven changes to this vital piece of DNA.

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Sep 22, 2021

Do Microbes Make Us Social?

Posted by in categories: biological, evolution, genetics, neuroscience

Microbes may have influenced the evolution of the social brain and behavior as a means to propagate their own genetic material.

—Cryan, Dinan, et al., November 2,019 Science.


In an effort to extend their territory, microbes may push us to socialize.

Sep 17, 2021

Directed evolution of a family of AAV capsid variants enabling potent muscle-directed gene delivery across species

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

Progress.


Replacing or editing disease-causing mutations holds great promise for treating many human diseases. Yet, delivering therapeutic genetic modifiers to specific cells in vivo has been challenging, particularly in large, anatomically distributed tissues such as skeletal muscle. Here, we establish an in vivo strategy to evolve and stringently select capsid variants of adeno-associated viruses (AAVs) that enable potent delivery to desired tissues. Using this method, we identify a class of RGD motif-containing capsids that transduces muscle with superior efficiency and selectivity after intravenous injection in mice and non-human primates. We demonstrate substantially enhanced potency and therapeutic efficacy of these engineered vectors compared to naturally occurring AAV capsids in two mouse models of genetic muscle disease. The top capsid variants from our selection approach show conserved potency for delivery across a variety of inbred mouse strains, and in cynomolgus macaques and human primary myotubes, with transduction dependent on target cell expressed integrin heterodimers.

Sep 16, 2021

Fossils and ancient DNA paint a vibrant picture of human origins

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

That fossil wasn’t enough to confirm Africa as our homeland. Since that discovery, paleoanthropologists have amassed many thousands of fossils, and the evidence over and over again has pointed to Africa as our place of origin. Genetic studies reinforce that story. African apes are indeed our closest living relatives, with chimpanzees more closely related to us than to gorillas. In fact, many scientists now include great apes in the hominid family, using the narrower term “hominin” to refer to humans and our extinct cousins.

In a field with a reputation for bitter feuds and rivalries, the notion of humankind’s African origins unifies human evolution researchers. “I think everybody agrees and understands that Africa was very pivotal in the evolution of our species,” says Charles Musiba, a paleoanthropologist at the University of Colorado Denver.

Paleoanthropologists have sketched a rough timeline of how that evolution played out. Sometime between 9 million and 6 million years ago, the first hominins evolved. Walking upright on two legs distinguished our ancestors from other apes; our ancestors also had smaller canine teeth, perhaps a sign of less aggression and a change in social interactions. Between about 3.5 million and 3 million years ago, humankind’s forerunners ventured beyond wooded areas. Africa was growing drier, and grasslands spread across the continent. Hominins were also crafting stone tools by this time. The human genus, Homo, arrived between 2.5 million and 2 million years ago, maybe earlier, with larger brains than their predecessors. By at least 2 million years ago, Homo members started traveling from Africa to Eurasia. By about 300,000 years ago, Homo sapiens, our species, emerged.

Sep 12, 2021

Cumrun Vafa: String Theory | Lex Fridman Podcast #204

Posted by in categories: evolution, mathematics, quantum physics, space

Cumrun Vafa is a theoretical physicist at Harvard. Please support this podcast by checking out our sponsors:
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CORRECTIONS:
- I’m currently hiring folks to help me with editing and image overlays so there may be some errors in overlays (as in this episode) as we build up a team. I ask for your patience.
- At 1 hour 27 minute mark, we overlay an image of Brian Greene. We meant to overlay an image of Michael Green, an early pioneer of string theory: https://bit.ly/michael-green-physicist.
- The image overlay of the heliocentric model is incorrect.

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Sep 10, 2021

Researchers decipher genetic mechanism that makes the midge invulnerable to harsh conditions

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

Circa 2014


New collaborative research published in the journal Nature Communications by scientists from Japan, Russia and the US contains the genetic analysis on a species of African midge, which can survive a wide array of extreme conditions including large variations in temperature, extreme drought and even airless vacuums such as space. The team successfully deciphered the genetic mechanism that makes the midge invulnerable to these harsh conditions. Prof. Noriyuki Satoh and Dr. Takeshi Kawashima of Prof. Satoh’s Marine Genomics Unit, as well as Prof. Alexander Mikeyhev of the Ecology and Evolution Unit, and Mr. Manabu Fujie and Dr. Ryo Koyanagi of the DNA Sequencing Section at the Okinawa Institute of Science and Technology Graduate University have contributed to the collaboration.

The midge, Polypedilum vanderplanki, is capable of anhydrobiosis, a unique state that allows an organism to survive even after losing 97% of its body water. Anhydrobiotic organisms are also able to survive other severe conditions such as extreme temperatures ranging from 90°C to-270°C, vacuums and high doses of radiation; all of which would be lethal to most other life forms.

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