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Archive for the ‘evolution’ category: Page 5

Sep 15, 2024

Decade-Long Study Challenges Traditional Views of Evolution

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

In a new study, scientists from Arizona State University and their collaborators studied genetic changes in a naturally isolated population of Daphnia pulex, a species of water flea. This tiny crustacean, nearly invisible to the naked eye, plays a vital role in freshwater ecosystems and provides a valuable insight into natural selection and evolution.

Their findings, recently published in the journal Proceedings of the National Academy of Sciences (PNAS), rely on a decade of research. Using advanced genomic techniques, the research team analyzed DNA samples from nearly 1,000 Daphnia.

They discovered that the strength of natural selection on individual genes varies significantly from year to year, maintaining variation and potentially enhancing the ability to adapt to future changing environmental conditions by providing raw material for natural selection to act on.

Sep 13, 2024

Loss of the Primal Eye, R.E.M as Phasic Transients, and the origins of Dreaming

Posted by in categories: chemistry, evolution, neuroscience

NEW PAPER — Loss of the Primal Eye in evolution, REM explained as phasic transients, and the emergence of DREAMING in E1 animals. MA dissertation Philosophy, University of Leeds 1995/1996.


There are a number of reasons why dreaming has been, and remains, an important area to philosophy. Dreams are ‘pure’ experiential phenomena not (seemingly) requiring input from the outside world via the special senses. As Aristotle puts it, “If all creatures, when the eyes are closed in sleep, are unable to see, and the analogous statement is true of the other senses, so that manifestly we perceive nothing when asleep; we may conclude that it is not by sense-perception we perceive a dream”. A major part of this dissertation is concerned with issues raised in Owen Flanagan’s (1995) article, Deconstructing Dreams: The Spandrels of Sleep. The Primal Eye/MVT account of consciousness gives p-dreaming a more central explanatory role, and I argue that p-dreams are not epiphenomena in the way Flanagan claims. An important omission from Flanagan’s account is any discussion of important dreaming-related phenomena. I look at lucid dreaming, hypnosis and other mental phenomena in relation to the evolutionary loss of the primal/ median/ parietal eye, and postulate that REM rapid eye movements are ‘phasic transients’ considering the E1 brain which includes the lateral eyes, as a consciousness-producing circuit. A brief account of Primal Eye/ Median Vision Theory is that capacity for abstract/ centrally evoked mentation is a direct result of the evolutionary loss of the primal eye. E2 (earlier hardwired brains with both primal and lateral eyes) have evolved over millions of years into E1 brain circuits analog(ous to infinite-state) types of self-regulating plastic circuits, with no primal/pineal eye, but retaining lateral eyes and the pineal gland. Loss of this ‘lockstep mechanism’ median/primal/ parietal/pineal eye not only allowed new sleeping mental phenomena such as dreaming; but also heralded in new types of waking mental abstraction freed from E2 involuntary primal eye direct (electro-chemical) responses to changes in the physical environment. These include daydreams, visualisation with both lateral eyes closed, self-volition or self-determined choices, and so on.

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Sep 12, 2024

The emerging view on the origin and early evolution of eukaryotic cells

Posted by in category: evolution

This Review summarizes key events in the emergence of cellular complexity via eukaryogenesis in the light of developments in environmental and comparative genomics during the past decade.

Sep 10, 2024

A New Look at Galaxy Boundaries: Discoveries from Deep Imaging of Cosmic Gas

Posted by in categories: evolution, space

“The circumgalactic medium plays a huge role in that cycling of that gas,” said Dr. Nikole Nielsen.


What are the exact sizes of galaxies, and are they bigger than they appear in deep space images? This is what a recent study published in Nature Astronomy hopes to address as an international team of researchers investigated the dust cloud that has long been hypothesized to orbit galaxies, indicating that galaxies are bigger than they appear. This study holds the potential to help scientists better understand the formation and evolution of galaxies, along with where the galaxy ends, and open space begins.

For the study, the researchers examined what’s known as the circumgalactic medium (CGM), which is a gas reservoir that extends far beyond a galaxy’s observable boundary, within a star-forming galaxy located 270 million light-years from Earth. Using novel imaging methods with ASTRO 3D, the researchers were able to observe this galaxy’s CGM extends as far out as 100,000 light-years beyond the galaxy’s observable boundary. Additionally, the team reports the physical aspects of the gas cloud, which is comprised of oxygen and hydrogen, changed as the gas cloud extended farther out.

Continue reading “A New Look at Galaxy Boundaries: Discoveries from Deep Imaging of Cosmic Gas” »

Sep 10, 2024

Green hydrogen: MXenes shows talent as catalyst for oxygen evolution

Posted by in categories: chemistry, evolution

The MXene class of materials has many talents. An international team led by HZB chemist Michelle Browne has now demonstrated that MXenes, properly functionalised, are excellent catalysts for the oxygen evolution reaction in electrolytic water splitting. They are more stable and efficient than the best metal oxide catalysts currently available. The team is now extensively characterising these MXene catalysts for water splitting at the Berlin X-ray source BESSY II and Soleil Synchrotron in France.

The findings have been published in Journal of Materials Chemistry A (“Enhancing the Oxygen Evolution Reaction activity of CuCo based Hydroxides with V 2 CTx MXene”).

The surface of a vanadium carbide MXene has been examined by Scanning Electron Microscopy. The beautiful structures are built by cobalt copper hydroxide molecules. (Image: B. Schmiedecke, HZB)

Sep 9, 2024

The Fate of Water on Mars: New Findings from Hubble and MAVEN Missions

Posted by in categories: evolution, particle physics, space

“In recent years scientists have found that Mars has an annual cycle that is much more dynamic than people expected 10 or 15 years ago,” said Dr. John Clarke.


What happened to all the liquid water on Mars and what can this teach us about Earth-like exoplanets? This is what a recent study published in Science Advances hopes to address as an international team of researchers investigated the atmospheric and atomic processes responsible for Mars losing its water over time. This study holds the potential to help researchers better understand the evolution of Mars, specifically regarding the loss of water, and what implications this holds for Earth-like exoplanets.

For the study, the researchers used a combination of data from NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) and Hubble Space Telescope (HST) spacecraft to measure the ratio of hydrogen and deuterium that escapes from Mars over three Martian years, with each Martian year comprising 687 Earth days. Deuterium is also called “heavy hydrogen” since it is a hydrogen atom with a neutron in its nucleus, making its mass greater than hydrogen.

Continue reading “The Fate of Water on Mars: New Findings from Hubble and MAVEN Missions” »

Sep 8, 2024

Revisiting the dynamics of interacting vector-like dark energy

Posted by in categories: cosmology, evolution, information science

We revise the dynamics of interacting vector-like dark energy, a theoretical framework proposed to explain the accelerated expansion of the universe. By investigating the interaction between vector-like dark energy and dark matter, we analyze its effects on the cosmic expansion history and the thermodynamics of the accelerating universe. Our results demonstrate that the presence of interaction significantly influences the evolution of vector-like dark energy, leading to distinct features in its equation of state and energy density. We compare our findings with observational data and highlight the importance of considering interactions in future cosmological studies.

Sep 6, 2024

Physicists capture first thickness-dependent transitions in two-dimensional magnetic material

Posted by in categories: evolution, physics

In the case of NiPS3, the researchers observed an intermediate symmetry breaking which leads to a vestigial order. Just as the term “vestigial” refers to the retention of certain traits during the process of evolution, the vestigial order here can also be viewed as the retention during the process of symmetry breaking.

This happens when the primary magnetic long-range order state melts or breaks down into a simpler form, in the NiPS3 case, a 2D vestigial order state (known as Z3 Potts-nematicity), as the material is thinned. Unlike conventional symmetry breaking, which involves the breaking of all symmetries, vestigial order only involves the breaking of some symmetries.

While there are numerous examples from a theoretical standpoint, experimental realizations of vestigial order have remained challenging. However, the investigation of this 2D magnetic material has shed the first light on this issue, demonstrating that such a phenomenon can be observed through dimension crossover.

Sep 4, 2024

Ancient Impact on Ganymede: New Evidence of a 93-Mile Asteroid’s Massive Effect

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

How did a giant impact 4 billion years ago affect Jupiter’s moon, Ganymede? This is what a recent study published in Scientific Reports hopes to address as a researcher from Kobe University investigated the geological changes known as a “furrow system” that Ganymede has exhibited since being struck by a giant asteroid in its ancient past, along with confirming previous hypotheses regarding the size of the asteroid. This study holds the potential to help scientists better understand how the very-active early solar system not only contributed to Ganymede’s but how such large impacts could have influenced the evolution of planetary bodies throughout the solar system.

“The Jupiter moons Io, Europa, Ganymede and Callisto all have interesting individual characteristics, but the one that caught my attention was these furrows on Ganymede,” said Dr. Naoyuki Hirata, who is an assistant professor in the Department of Planetology at Kobe University and sole author of the study. “We know that this feature was created by an asteroid impact about 4 billion years ago, but we were unsure how big this impact was and what effect it had on the moon.”

For the study, Dr. Hirata used a series of mathematical calculations to ascertain the size of the object that impacted Ganymede billions of years ago along with the angle of impact that produced the furrow system. In the end, Dr. Hirata determined that the impactor’s radius was approximately 93 miles (150 kilometers) and the angle of impact was potentially between 60 to 90 degrees, resulting in the furrows that overlay a significant portion Ganymede’s surface. For context, Ganymede is not only the largest moon in the solar system at a radius of 1,637 miles (2,634 kilometers), but it is also larger than the planet Mercury.

Aug 30, 2024

Newly-discovered Star could provide New Insights into the Evolution of Stars

Posted by in categories: chemistry, evolution, space

A new study published in The Astrophysical Journal, led by Assistant Professor of Astronomy Rana Ezzeddine and UF alumnus Jeremy Kowkabany, with collaborators, reports the discovery of a star that challenges astronomers’ understanding of star evolution and formation of chemical elements, and could suggest a new stage in their growth cycle.

It is widely accepted that as stars burn, they lose lighter elements like lithium in exchange for heavier elements like carbon and oxygen, but an analysis of this new star revealed that not only was its lithium content high for its age, but was higher than the normal level for any star at any age.

This star, named J0524-0336 based on its coordinates in space, was discovered recently by Ezzeddine as part of a different study that used surveying to look for older stars in the Milky Way. It is an evolved star, meaning that it is in the later stages of its “life” and is beginning to grow unstable. That also means that it is much larger and brighter than most other stars of its type, estimated to be about 30 times the size of the sun.

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