Life on Mars Likely

The mystery of life’s origins on Earth has long puzzled scientists, but a recent discovery on Mars might be shedding new light on this profound question, while also inching closer to finding life on Mars.

NASA’s Curiosity Mars rover has uncovered a patchwork of well-preserved ancient mud cracks, forming a distinctive hexagonal pattern, signaling the presence of wet-dry cycles on early Mars. These cycles could be key to the assembly of complex chemical building blocks necessary for microbial life.

A study published in Nature elaborates on the importance of this discovery. The lead author, William Rapin of France’s Institut de Recherche en Astrophysique et Planétologie, expressed his excitement, stating, “These particular mud cracks form when wet-dry conditions occur repeatedly – perhaps seasonally.”

Mud cracks named “Pontours”
Curiosity’s ongoing exploration of Mount Sharp, which stands 5 kilometers high in Gale Crater, has brought about this groundbreaking revelation. 

In 2021, after drilling a sample from a rock target nicknamed “Pontours,” located in a transitional zone between a clay-rich layer and a layer enriched with salty minerals called sulfates, the rover spotted these telling mud cracks.  READ MORE...

New Twist in Human Origins

A study published in the journal Nature has proposed a new model for human evolution, asserting that modern Homo sapiens stemmed from multiple genetically diverse populations across Africa rather than a single ancestral population. This conclusion was reached after researchers analyzed genetic data from present-day African populations, including 44 newly sequenced genomes from the Nama group of southern Africa.

Contemporary DNA evidence suggests that humans emerged from the interaction of multiple populations living across the continent.

A new study in Nature challenges prevailing theories, suggesting that Homo sapiens evolved from multiple diverse populations across Africa, with the earliest detectable split occurring 120,000-135,000 years ago, after prolonged periods of genetic intermixing.

There is broad agreement that Homo sapiens originated in Africa. But there remain many uncertainties and competing theories about where, when, and how.


In a paper published on May 17, 2023, in Nature, an international research team led by McGill University and the University of California-Davis suggest that, based on contemporary genomic evidence from across the continent, there were humans living in different regions of Africa, migrating from one region to another and mixing with one another over a period of hundreds of thousands of years. 

This view runs counter to some of the dominant theories about human origins in Africa.

Competing theories about human origins in Africa
One theory holds that, about 150,000 years ago, there was a single central ancestral population in Africa from which other populations diverged. 

Another suggests that this central ancestral population was the result of the mixing of modern humans with a Neanderthal-like hominins (human-like beings), resulting in a leap forward in human evolution, as has been suggested took place in Eurasia.  READ MORE...

Setting Aside ONE THIRD of our Planet for Nature

It's being called a last chance for nature - 100 countries backing calls to protect 30% of the planet.  The aim is to reach this goal by 2030 and conserve forests and other vital ecosystems in order to restore the natural world.  The "30x30" target is the key ambition of the UN biodiversity summit, COP 15

But as the talks in Montreal, Canada, move into their final days, there is division over this and many other targets.  Biodiversity refers to all living things, from polar bears to plankton, and the way they fit together to sustain life on Earth.

Scientists have warned that with forests and grasslands being lost at unprecedented rates and oceans under pressure from pollution and over-fishing, humans are pushing the Earth beyond safe limits. This includes increasing the risk of diseases, like SARs CoV-2, Ebola and HIV, spilling over from wild animals into human populations.

Under the proposed agreement, countries would sign up to targets to expand protected areas, such as nature reserves. It draws inspiration from the so-called "father of biodiversity", the biologist Edward O Wilson, who called for half of Earth to be protected.

But there is debate over how much land and sea to include, and some scientists fear the targets may be diluted.  READ MORE...

Ancient Pyramids in the Amazon

Secret pyramids and small cities dating back to the Middle Ages have been discovered in one of the densest parts of the Amazon.


According to a journal published in Nature, a new type of advanced laser-mapping technology was used to penetrate the dense Bolivian rainforest of the region.


By deploying this new research tool, archaeologists have now made the landmark discovery of town-like civilisations in the area.


The discovery is particularly exciting for researchers as this now proves that Amazonians lived together in township-like structures before the Spanish set foot on South American soil.


Colorado State University archaeologist Chris Fisher said the new technology will usher in a new age of research in the Amazon, as per The Wall Street Journal.


"This is the first of what I hope will be a huge series of studies that will blow the lid off of preconceptions about what pre-Hispanic polities looked like in the Amazon in terms of their complexity, size and density," he said.


Dr Fisher said that before Hispanic occupation in the 16th century it was believed Amazonians lived in small groups with limited social development and agricultural systems.


However, this landmark discovery indicates that may not have been the case.


Dr Fisher added: "These sites are pushing the boundaries of what we would call cities."


Scientists from Germany and the UK searched six regions of the Amazon in Bolivia using a helicopter equipped with light detection and ranging equipment.


The new type of research has paid them back in spades, with 26 settlements revealed to them in unprecedented new detail.  READ MORE...

The Width of an Atom

There’s been no greater act of magic in technology than the sleight of hand performed by Moore’s Law. Electronic components that once fit in your palm have long gone atomic, vanishing from our world to take up residence in the quantum realm.

But we’re now brushing the bitter limits of this trend. In a paper published in Nature this week, scientists at Tsinghua University in Shanghai wrote that they’ve built a graphene transistor gate with a length of 0.34 nanometers (nm)—or roughly the size of a single carbon atom.

The gate, a chip component that switches transistors on and off, is a critical measure of transistor size. Previous research had already pushed gate lengths to one nanometer and below. By scaling gate lengths down to the size of single atoms, the latest work sets a new mark that’ll be hard to beat. “In the future, it will be almost impossible for people to make a gate length smaller than 0.34 nm,” the paper’s senior author Tian-Ling Ren told IEEE Spectrum. “This could be the last node for Moore’s Law.”

Etching a 2D Sandwich
Transistors have a few core components: the source, the drain, the channel, and the gate. Electrical current flows from the source, through the channel, past the gate, and into the drain. The gate switches this current on or off depending on the voltage applied to it.

Recent advances in extreme transistor gate miniaturization rely on some fascinating materials. In 2016, for example, researchers used carbon nanotubes—which are single-atom-thick sheets of carbon rolled into cylinders—and a 2D material called molybdenum disulfide to achieve a gate length of one nanometer. Silicon is a better semiconductor, as electrical currents encounter more resistance in molybdenum disulfide, but when gate lengths dip below five nanometers, electrons leak across the gates in silicon transistors. Molybdenum disulfide’s natural resistance prevents this leakage at the tiniest scales.

Building on this prior work, the researchers in the most recent study also chose molybdenum disulfide for their channel material and a carbon-based gate. But instead of carbon nanotubes, which are a nanometer across, they looked to go smaller. Unroll a nanotube and you get a sheet made of carbon atoms called graphene. Graphene has all kinds of interesting properties, one of which is excellent conductivity. The width and length of a graphene sheet are, of course, bigger than a nanotube—but the edge is a single carbon atom thick. The team cleverly exploited this property.  READ MORE...

Culture 40,000 Years Old

The migration of homo sapiens from Africa to the rest of the globe is an enduring point of fascination for archaeologists, who have been piecing together human movements across history since the dawn of the discipline. A new study published in Nature last week has helped unlock another piece of the puzzle.

That study, conducted by a research team led by Fa-Gang Wang, is an examination of Xiamabei, a 40,000-year-old archaeological site in northern China. At this site, researchers discovered evidence of a culture that processed ochre, which is used to make pigments. The discovery may seem like a small one, but it led the researchers to rethink how modern humanity evolved.

Ochre is a pigment found in clay, and its presence at archaeological sites suggests the people who lived in Xiamabei had advanced cognitive skills, partly because its points to creativity. However, the pigment can also be used to more practical ends, such as tanning hides.

At Xiamabei, researchers discovered that the humans at the site brought different deposits of ochre there and processed it through pounding and abrasion. This resulted pigments of varying color and consistency. Evidence of the pounding was found on a limestone slab where this processing took place. These humans produced such large quantities of ochre that the slab was stained with pigment.

The unique nature of the tools and processing method found at Xiamabei suggest that instead of one continuous wave of migration across Asia, colonization of this territory happened in distinct phases, the researchers said. “Our findings show that current evolutionary scenarios are too simple,” Michael Petraglia of the Max Planck Institute said in an interview with Science Daily. “Modern humans, and our culture, emerged through repeated but differing episodes of genetic and social exchanges over large geographic areas, rather than as a single, rapid dispersal wave across Asia.”

Another clue as to this disjointedness is what the researchers didn’t find: formal bone tools and ornaments, which were available at the time, but which evidently were not used by some of Xiamabei’s oldest inhabitants.

Swiss Cheese Bubble Created by Supernovas

 

Artist's illustration of the Local Bubble with the sun's location in the center and star formation occurring on the bubble's surface. (Image credit: Leah Hustak (STScI))

In the new study, published online Jan. 12 in the journal Nature, researchers accurately mapped the star-forming regions surrounding the Local Bubble and, in doing so, calculated how fast the superbubble is expanding. 

This allowed the team to work out exactly how many supernovas were needed to carve out the gigantic cosmic void and better understand how star-forming regions are created across the Milky Way.Earth is slap bang in the middle of a 1,000 light-year-wide bubble with a dense surface birthing thousands of baby stars. Researchers have long wondered what created this "superbubble." Now, a new study suggests that at least 15 powerful star explosions inflated this cosmic bubble.

Astronomers in the 1970s first discovered the gigantic void, known as the Local Bubble, after realizing that no stars had formed inside the blob for around 14 million years. The only stars inside the bubble either existed before the bubble emerged or formed outside the void and are now passing through; the sun is one such trespasser. 

This setup had suggested that several supernovas were responsible for this void. Those stellar explosions, the researchers said, would have blasted the materials needed to make new stars, such as hydrogen gas, to the edge of a huge area in space, leaving behind the Local Bubble that's surrounded by a frenzy of star births.  READ MORE...

Human Neurons and Mammels

Human neurons have fewer ion channels, which might have allowed the human brain to divert energy 

to other neural processes.

Neurons communicate with each other via electrical impulses, which are produced by ion channels that control the flow of ions such as potassium and sodium. In a surprising new finding, MIT neuroscientists have shown that human neurons have a much smaller number of these channels than expected, compared to the neurons of other mammals.


The researchers hypothesize that this reduction in channel density may have helped the human brain evolve to operate more efficiently, allowing it to divert resources to other energy-intensive processes that are required to perform complex cognitive tasks.


“If the brain can save energy by reducing the density of ion channels, it can spend that energy on other neuronal or circuit processes,” says Mark Harnett, an associate professor of brain and cognitive sciences, a member of MIT’s McGovern Institute for Brain Research, and the senior author of the study.

MIT neuroscientists analyzed pyramidal neurons from several different mammalian species, including,

from left to right, ferret, guinea pig, rabbit, marmoset, macaque, and human. 

Credit: Courtesy of the researchers

Harnett and his colleagues analyzed neurons from 10 different mammals, the most extensive electrophysiological study of its kind, and identified a “building plan” that holds true for every species they looked at — except for humans. They found that as the size of neurons increases, the density of channels found in the neurons also increases.

However, human neurons proved to be a striking exception to this rule.

“Previous comparative studies established that the human brain is built like other mammalian brains, so we were surprised to find strong evidence that human neurons are special,” says former MIT graduate student Lou Beaulieu-Laroche.

Beaulieu-Laroche is the lead author of the study, which was published on November 10, 2021, in Nature.  READ MORE...

Gut Bacteria

People who live to age 100 and beyond may have special gut bacteria that help ward off infections, according to a new study from Japan.

The results suggest that these bacteria, and the specific compounds they produce — known as "secondary bile acids" — could contribute to a healthy gut and, in turn, healthy aging.

Still, much more research is needed to know whether these bacteria promote exceptionally long life spans. The current findings, published Thursday (July 29) in the journal Nature, only show an association between these gut bacteria and living past 100; they don't prove that these bacteria caused people to live longer, said study senior author Dr. Kenya Honda, a professor in the Department of Microbiology and Immunology at the Keio University School of Medicine in Tokyo.

"Although it might suggest that these bile-acid-producing bacteria may contribute to longer life spans, we do not have any data showing the cause-and-effect relationship between them," Honda told Live Science.

The community of bacteria and other microorganisms that live in the gut, known as the gut microbiome, is known to play a role in our health and changes as we age. For example, having less diversity in the types of gut bacteria has been linked with frailty in older adults. But researchers suspected that people who reach age 100 may have special gut bacteria that contribute to good health. 

Indeed, centenarians tend to be at lower risk of chronic diseases and infections compared with older adults who don't reach this milestone.  READ MORE

Do We Need Religious Institutions?

 TEN COMMANDMENTS

1. You shall have no other Gods before me
2. You shall not make for yourselves an idol
3. You shall not misuse the name of the LORD your God
4. Remember the Sabbath day by keeping it holy
5. Honor your father and your mother
6. You shall not murder
7. You shall not commit adultery
8. You shall not steal
9. You shall not give false testimony
10. You shall not covet

Religious institutions put the ten commandment in their sermons that the clergy deliver to congregations over and over again in a variety of lessons and proverbs, etc. in the hopes that their congregations will finally follow Jesus' teachings...

But, why do we make the assumption that our congregations are intellectual void and cannot manage their own feelings and follow the ten commandments on their own without constant reminders?

I am an adult.

I am an educated adult.

I am a well educated adult.

I am a retired adult after working for 45 years.

I have read the Bible cover to cover.

Do I need to be constantly reminded by clergy that I should follow the Ten Commandments or do I think that I can remind myself and use my own personality to make sure that I adhere to the Ten Commandments?

If I can do this on my own...  why do I need to attend Church on Sundays?

It is said that there is fellowship going on in Church with like minded people...  and, while that may be true to some extent, my experience is that most of these people in Church that I saw behave in a completely different manner Monday through Saturday when not in Church...  consequently, I have no desire to fellowship with hypocrites...

My fellowship is completed with NATURE...  animals, the environment, rain showers, snow falls, spring flowers, birds of all shapes and sizes, sunsets and sunrises...  and all the fresh air that I can breathe into my lungs by living in the country.

I fellowship with God and His creations everyday...

It don't no better than that...

Fall Morning Breakfast

Most people, I am assuming, if they eat breakfast at all, it is either at home before they leave for work or they drop by a fast food restaurant and get something on the go or they stop at a sit down restaurant and order a working man's breakfast of eggs, grits, sausage or bacon, and pancakes...  of course, this hearty breakfast is likely to last them throughout the day until they return home, typically after dark for a cold or heated in the microwave dinner.

Unlike most of these people, I am retired and my breakfast is late in the morning usually more brunch than breakfast and only after I have been awake for 2-3 hours do I feel like eating anything more than just drinking coffee.

Usually, I will get a package of grits and add water, toss it in the microwave along with a vege sausage while I am scrambling up an egg that I will mix all together with some grated cheese.  If I am tired of scrambled eggs, I will toast an English Muffin and fry an egg along with a vege sausage and a slice of American Cheese.

Once my breakfast is cooked, I will sit on the back screened in porch and watch the bluebirds fly in and out of the house I built for them using old decking.

My breakfast is usually only 300 calories but sometimes I add a little something extra and my intake grows to 500 or so.  My plan is to eat no more than 500 calories at each meal along with snack(s) that do not exceed 500 calories so that my total daily intake is less than 2,000 calories each day.  I would like to reduce that intake to 1,500 making sure that protein, dairy, grain, veges, and fruit is most of the time included.

I like Fall Morning Breakfasts because I can sit outside and watch nature while I eat...  this usually consists of a variety of birds, rabbits, butterflies, and squirrels...  but, if I decide to sit on my front porch, I am just about guaranteed to see a family of deer in the field across the street.

It is a simple but rewarding life.