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Feb 20, 2023

Researchers propose new mechanism for early chemical evolution

Posted by in categories: chemistry, evolution, space

Scientists from The Ohio State University have a new theory about how the building blocks of life—the many proteins, carbohydrates, lipids and nucleic acids that compose every organism on Earth—may have evolved to favor a certain kind of molecular structure.

It has to do with a concept called chirality. A geometric property inherent to certain , chirality can dictate a molecule’s shape, chemical reactivity, and how it interacts with other matter. Chirality is also sometimes referred to as handedness, as it can be best described as the dichotomy between our hands: Though they are not identical, the right and the left hand are mirror images of each other, and can’t be superimposed, or exactly overlaid on one another.

In the journal ACS Earth and Space Chemistry, researchers now propose a new model of how the molecules of life may have developed their “handedness.”

Feb 18, 2023

The Genes We Lost Along the Way

Posted by in categories: biotech/medical, evolution

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Our DNA holds thousands of dead genes and we’ve only just begun to unravel their stories. But one thing is already clear: we’re not just defined by the genes that we’ve gained over the course of our evolution, but also by the genes that we’ve lost along the way.

Thanks to these illustrators for their wonderful hominin illustrations featured throughout this episode!
Julio Lacerda: https://twitter.com/JulioTheArtist.
Fabrizio de Rossi: https://www.facebook.com/ArtofFabricious/
Jack Byrley: https://twitter.com/bedupolker.

Continue reading “The Genes We Lost Along the Way” »

Feb 17, 2023

Study finds 155 tiny new genes evolving in humans

Posted by in categories: biotech/medical, evolution

This process is no less relevant to humans than any other species in nature, but since our species is such an evolutionary newcomer, the extent of its influence — and how it might work today — is still difficult to pin down.

The challenge: A team of researchers in Greece and Ireland, led by Nikolaos Vakirlis at the Alexander Fleming Biomedical Sciences Research Center in Athens, argues that a key to understanding human evolution lies with short sequences of DNA named “open reading frames” (ORFs). These structures are small sections of the genome that encode tiny protein molecules — microproteins — which can perform a diverse range of crucial biological tasks, from regulating muscle performance to alerting cells to damaging stresses.

Due to their minuscule sizes, ORFs are notoriously difficult to study. Because of this, their full relevance has gone under the radar in mainstream genomics research until recently, and even today, they still aren’t considered to be proper genes in themselves. For Vakirlis’ team, this potential oversight masks the fact that the microproteins encoded by ORFs can develop their own de novo sequences over generations, which may eventually develop into new genes.

Feb 16, 2023

7 new spider species found in the depths of Israeli caves

Posted by in categories: evolution, genetics

A new study has identified seven spider species previously unknown to science in the depths of Israeli caves, with the surprise finding that they are evolutionarily closer to arachnids found in southern Europe than to their neighbors at cave entrances in Israel.

The peer-reviewed research, published in the Molecular Phylogenetics and Evolution journal, was conducted by scientists from the Hebrew University in Jerusalem and the University of Madison-Wisconsin.

The study “has extensive scientific implications for uncovering the evolution of speciation in caves and the historical, geographic and climatic processes that occurred in Israel,” the Hebrew University said in a statement.

Feb 16, 2023

Carbonaceous Dust Grains Within Galaxies Seen In The First Billion Years Of Cosmic Time

Posted by in categories: cosmology, evolution

Interstellar dust captures a significant fraction of elements heavier than helium in the solid state and is an indispensable component both in theory and observations of galaxy evolution.

Dust emission is generally the primary coolant of the interstellar medium (ISM) and facilitates the gravitational collapse and fragmentation of gas clouds from which stars form, while altering the emission spectrum of galaxies from ultraviolet (UV) to far-infrared wavelengths through the reprocessing of starlight. However, the astrophysical origin of various types of dust grains remains an open question, especially in the early Universe.

Here we report direct evidence for the presence of carbonaceous grains from the detection of the broad UV absorption feature around 2175A˚ in deep near-infrared spectra of galaxies up to the first billion years of cosmic time, at a redshift (z) of ∼7. This dust attenuation feature has previously only been observed spectroscopically in older, more evolved galaxies at redshifts of z3. The carbonaceous grains giving rise to this feature are often thought to be produced on timescales of hundreds of millions of years by asymptotic giant branch (AGB) stars. Our results suggest a more rapid production scenario, likely in supernova (SN) ejecta.

Feb 15, 2023

RNA’s ‘joints’ play key role in our gene expression, scientists find

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

University of Chicago scientists have discovered a new wrinkle in our understanding of how our genes work. The team, led by Chuan He, the UChicago John T. Wilson Distinguished Service Professor of Chemistry, Biochemistry and Molecular Biology, shed light on a longstanding puzzle involved in a common way our genes are modified that is known as RNA methylation.

Published Jan. 27 in Science, the finding could have implications for for disease, as well as our picture of gene expression, development, and evolution.

For more than a decade, Chuan He’s laboratory has been focused on trying to unravel the puzzle of a phenomenon called RNA methylation, which we are increasingly understanding plays a key role in our bodies and lives—everything from cancer to PTSD to aging.

Feb 15, 2023

Demonstration of universal time-reversal for qubit processes

Posted by in categories: evolution, quantum physics

In quantum mechanics, the unitary nature of time evolution makes it intrinsically reversible, given control over the system in question. Remarkably, there have been several recent demonstrations of protocols for reverting unknown unitaries in scenarios where even the interactions with the target system are unknown. These protocols are limited by their probabilistic nature, raising the fundamental question of whether time-reversal could be performed deterministically. Here we show that quantum physics indeed allows for this by exploiting the non-commuting nature of quantum operators, and demonstrate a recursive protocol for two-level quantum systems with an arbitrarily high probability of success. Using a photonic platform, we achieve an average rewinding fidelity of over 95%. Our protocol, requiring no knowledge of the quantum process to be rewound, is optimal in its running time, and brings quantum rewinding into a regime of practical relevance.

Published by Optica Publishing Group under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Feb 15, 2023

Gene Expression in Neurons Solves a Brain Evolution Puzzle

Posted by in categories: biological, evolution, neuroscience

𝐓𝐡𝐞 𝐧𝐞𝐨𝐜𝐨𝐫𝐭𝐞𝐱 𝐬𝐭𝐚𝐧𝐝𝐬 𝐨𝐮𝐭 𝐚𝐬 𝐚 𝐬𝐭𝐮𝐧𝐧𝐢𝐧𝐠 𝐚𝐜𝐡𝐢𝐞𝐯𝐞𝐦𝐞𝐧𝐭 𝐨𝐟 𝐛𝐢𝐨𝐥𝐨𝐠𝐢𝐜𝐚𝐥 𝐞𝐯𝐨𝐥𝐮𝐭𝐢𝐨𝐧. 𝐀𝐥𝐥 𝐦𝐚𝐦𝐦𝐚𝐥𝐬 𝐡𝐚𝐯𝐞 𝐭𝐡𝐢𝐬 𝐬𝐰𝐚𝐭𝐡 𝐨𝐟 𝐭𝐢𝐬𝐬𝐮𝐞 𝐜𝐨𝐯𝐞𝐫𝐢𝐧𝐠 𝐭𝐡𝐞𝐢𝐫 𝐛𝐫𝐚𝐢𝐧, 𝐚𝐧𝐝 𝐭𝐡𝐞 𝐬𝐢𝐱 𝐥𝐚𝐲𝐞𝐫𝐬 𝐨𝐟 𝐝𝐞𝐧𝐬𝐞𝐥𝐲 𝐩𝐚𝐜𝐤𝐞𝐝 𝐧𝐞𝐮𝐫𝐨𝐧𝐬 𝐰𝐢𝐭𝐡𝐢𝐧 𝐢𝐭 𝐡𝐚𝐧𝐝𝐥𝐞 𝐭𝐡𝐞 𝐬𝐨𝐩𝐡𝐢𝐬𝐭𝐢𝐜𝐚𝐭𝐞𝐝 𝐜𝐨𝐦𝐩𝐮𝐭𝐚𝐭𝐢𝐨𝐧𝐬 𝐚𝐧𝐝 𝐚𝐬𝐬𝐨𝐜𝐢𝐚𝐭𝐢𝐨𝐧𝐬 𝐭𝐡𝐚𝐭 𝐩𝐫𝐨𝐝𝐮𝐜𝐞 𝐜𝐨𝐠𝐧𝐢𝐭𝐢𝐯𝐞 𝐩𝐫𝐨𝐰𝐞𝐬𝐬. 𝐒𝐢𝐧𝐜𝐞 𝐧𝐨 𝐚𝐧𝐢𝐦𝐚𝐥𝐬 𝐨𝐭𝐡𝐞𝐫 𝐭𝐡𝐚𝐧 𝐦𝐚𝐦𝐦𝐚𝐥𝐬 𝐡𝐚𝐯𝐞 𝐚 𝐧𝐞𝐨𝐜𝐨𝐫𝐭𝐞𝐱, 𝐬𝐜𝐢𝐞𝐧𝐭𝐢𝐬𝐭𝐬 𝐡𝐚𝐯𝐞 𝐰𝐨𝐧𝐝𝐞𝐫𝐞𝐝 𝐡𝐨𝐰 𝐬𝐮𝐜𝐡 𝐚 𝐜𝐨𝐦𝐩𝐥𝐞𝐱 𝐛𝐫𝐚𝐢𝐧 𝐫𝐞𝐠𝐢𝐨𝐧 𝐞𝐯𝐨𝐥𝐯𝐞𝐝.

The brains of reptiles seemed to offer a clue. Not only are reptiles the closest living relatives of mammals, but their brains have a three-layered structure called a dorsal ventricular ridge, or DVR, with functional similarities to the neocortex.


The neocortex stands out as a stunning achievement of biological evolution. All mammals have this swath of tissue covering their brain, and the six layers of densely packed neurons within it handle the sophisticated computations and associations that produce cognitive prowess. Since no animals other than mammals have a neocortex, scientists have wondered how such a complex brain region evolved.

Continue reading “Gene Expression in Neurons Solves a Brain Evolution Puzzle” »

Feb 14, 2023

What If Neanderthals Had Outlived Homo Sapiens?

Posted by in category: evolution

An anthropologist imagines a world in which Neanderthals—and their relationships with the environment and one another—survived evolution.

Feb 14, 2023

Number of fires in the Brazilian Amazon in August-September 2022 was highest since 2010

Posted by in categories: evolution, space

The number of active fires recorded in the Brazilian Amazon in August-September 2022 was the highest since 2010, according to an article published in the journal Nature Ecology & Evolution. Besides the record number of fires (74,398), the researchers found they were due not to extreme drought, as in 2010, but to recent deforestation by humans.

“The idea of publishing our findings came up when we analyzed data provided free of charge by the Queimadas program,” said Guilherme Mataveli, first author of the article. ‘Queimadas’ in Portuguese means burnings, and he was referring to the forest monitoring service run by the National Space Research Institute (INPE). Mataveli is currently a postdoctoral researcher in INPE’s Earth Observation and Geoinformatics Division.

The number of fires typically rises every year in August and September, when the weather favors fire in about half of the Amazon. “But the surge in the number of fires in 2010 was due to an extreme drought event that occurred in a large part of the region, whereas nothing similar occurred in 2022, so other factors must have been to blame,” Mataveli said.

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