Exploring How Gas Fuels Diverse Microbial Life in Caves – Sciworthy

Here’s an SEO-optimized version of the given content, maintaining the original HTML structure:

Caves are often dark, damp, and remote. While they lack the nutrients and energy sources that sustain life in other ecosystems, they still host a diverse array of bacteria and archaea. But how do these microorganisms acquire enough energy to thrive? A team of researchers from Australia and Europe investigated this intriguing question by examining Australian caves.

Previous studies identified that microorganisms in nutrient-poor soils can harness energy from the atmosphere through trace gases, including hydrogen, carbon monoxide, and methane. These gases are present in minute quantities, classified as trace gases. Microbes possess specific proteins that can accept electrons from these gas molecules, enabling them to utilize these gases as energy sources, such as hydrogenase, dehydrogenase, or monooxygenase, fueling their metabolic processes.

The Australian research team hypothesized that cave-dwelling microbes may be using trace gases for survival. To test this, they studied four ventilated caves in southeastern Australia. The researchers collected sediment samples at four points along a horizontal line that extended from the cave entrance to 25 meters (approximately 80 feet) deep inside the cave, resulting in a total of 94 sediment samples.

The team treated the sediment samples with specific chemicals to extract microbial DNA, using it to identify both the abundance and diversity of microorganisms present. They found multiple groups of microorganisms throughout the cave, including Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexota, and Thermoproteota. Notably, the density and diversity of microbes were significantly higher near the cave entrance, with three times more microorganisms in those regions compared to further inside.

The team utilized gene sequencing to analyze the microbial DNA for genes linked to trace gas consumption. Results revealed that 54% of cave microorganisms carried genes coding for proteins involved in utilizing trace gases like hydrogenases, dehydrogenases, and monooxygenases.

To assess the generality of their findings, the researchers searched existing data on microbial populations from 12 other ventilated caves worldwide. They discovered that genes for trace gas consumption were similarly prevalent among other cave microorganisms, concluding that trace gases might significantly support microbial life and activity in caves.

Next, the researchers measured gas concentrations within the caves. They deployed static magnetic flux chambers to collect atmospheric gas samples at four points along the sampling line, capturing 25 milliliters (about 1 ounce) of gas each time. Using a gas chromatograph, they analyzed the samples and found that the concentrations of hydrogen, carbon monoxide, and methane were approximately four times higher near the cave entrance compared to deeper areas. This suggests that microorganisms might be metabolizing these trace gases for energy.

To validate their findings further, they constructed a static magnetic flux chamber in the lab, incubating cave sediment with hydrogen, carbon monoxide, and methane at natural concentration levels. They confirmed that microbes also consumed trace gases in controlled conditions.

Finally, the researchers explored how these cave microbes obtained organic carbon. They conducted carbon isotope analysis, focusing on carbon-12 and carbon-13 ratios, which can vary based on microbial metabolic processes. Using an isotope ratio mass spectrometer, they determined that cave bacteria had a lower percentage of carbon-13, indicating their reliance on trace gases to generate carbon within the cave ecosystem.

The researchers concluded that atmospheric trace gases serve as a crucial energy source for microbial communities in caves, fostering a diverse array of microorganisms. They recommended that future studies examine how climatic changes, such as fluctuations in temperature and precipitation, might influence the use of atmospheric trace gases by cave-dwelling microorganisms.

Post views: 318

This version enhances the original content with relevant keywords while retaining the structure and integrity of the HTML tags.

Source: sciworthy.com

Water-formed Caves on Mars Might Harbor Evidence of Ancient Life

Caves in the Hebrus Valley of Mars may have been sculpted by ancient water flows

NASA Mars Earth Surveyor

Subsurface caves shaped by flowing water on Mars may have provided ideal conditions for life, with potential remnants still present today.

Throughout Mars, numerous openings resembling cave entrances are found, primarily near volcanic regions. This implies these features were likely formed by processes related to volcanic activity rather than water.

Earth is home to numerous karst caves, created by the dissolution of soluble rock by water. However, scientists have yet to find equivalent caves on Mars, despite evidence indicating the planet was once covered in water billions of years ago.

Currently, Ding Vermicelli, a professor at Shenzhen University in China, has identified eight caves that seem to have been formed by ancient water flows instead of volcanic activity. These caves are situated in the Hebrus Gorge, a northwestern region characterized by extensive valleys and depressions likely shaped by ancient floods.

Previous Mars missions, including NASA’s Mars Global Surveyor (which orbited Mars from 1997 to 2006), have mapped these caves. Ding and his team analyzed material near one cave entrance using spectroscopic data from that mission, revealing a notable presence of carbonate and sulfate minerals typically associated with water.

They also detected signs of an ancient stream ending near the cave entrance, similar to patterns seen near karst caves on Earth. James Baldini from Durham University, UK, noted, “On a map, you’d expect a river to emerge to the surface only to disappear suddenly, as the cave system absorbs its water.”

Daniel Le Corret from the University of Kent in the UK mentioned that while the mineralogical and geological data implies these may be water caves, they appear quite similar to other Martian caves of volcanic origin. “I’ve spent countless hours evaluating the global catalog of Martian caves and these resemble known volcanic formations,” he said.

If these caves are indeed formed by water, they might be excellent locations for searching for life. “For life to exist, water and a protective environment from Mars’ intense surface radiation are essential,” Baldini remarked. “Volcanic caves and lava tubes also present good avenues for potential life, though they don’t necessarily involve water.”

Mars’ water caves may contain stalagmites—bulbous rock formations generally found in Earth’s karst caves—and could act as time capsules of Mars’ ancient climate conditions, such as temperature.

However, stalagmites require thousands of years of sustained water flow to develop, and determining their formation timing could be challenging, even if rovers or drones succeed in collecting samples, according to Baldini.

Mysteries of the Universe: Cheshire, England

Join a weekend with some of science’s leading minds as you delve into the enigmas of the universe, featuring a tour of the renowned Lovell Telescope.

Topic:

Source: www.newscientist.com

Ancient Cannibalism Evidence Discovered in Human Bones from Spanish Caves

Cut marks on the foot bone from El Mirador cave, Spain

iphes-cerca

The discovery of human remains in caves in northern Spain indicates that Neolithic people may have resorted to cannibalism after battles.

Francesc Marginedas from the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) in Tarragona, along with his team, examined fragments from 650 human remains found in El Mirador cave on Mount Atapuerca. These remains date back approximately 5,700 years and belong to 11 individuals.

All examined bones displayed evidence that these individuals had been consumed by other humans. Some exhibited chop markings made by a stone tool, while others showed translucent portions with gently rounded edges. Some of the long bones were fractured open with stones to access the bone marrow, and smaller bones like metatarsals and ribs had clear human bite marks.

This research supports the notion that cannibalistic practices were more prevalent in human history than previously believed.

El Mirador marks at least the fifth significant site in Spain with notable evidence of cannibalism during the Neolithic era, a shift period from foraging to agriculture, according to Margida. “There’s a growing understanding that such behavior was more frequent than we anticipated.”

The motives behind these cannibalistic acts remain unclear. Some archaeological sites show skull cups indicating a ritualistic aspect to cannibalism, while others hint at survival strategies during dire circumstances.

However, Marsidas and his team propose that the findings at El Mirador suggest these acts were linked to warfare. There was a significant amount of animal remains, and no signs of nutritional stress among the humans involved, indicating this early agricultural community was not struggling with food scarcity. Their findings offer no indication of ritualistic behavior, as human bones were found alongside animal remains.

The ages of the individuals ranged from under seven to over fifty, implying that an entire family unit may have been lost to conflict. Radiocarbon dating indicated that all 11 individuals were killed and consumed within a few days.

This evidence reflects patterns of conflict and cannibalism, which have also been noted at two other Neolithic sites: the Von Bregore Caves in France and Helxheim in Germany. This period appears marked by instability and violence due to community clashes with neighboring groups and newcomers.

While Margida and his colleagues are uncertain about the reasons behind these cannibalistic practices, historical ethnographic studies suggest that such acts during warfare can serve as a method of “ultimate exclusion.” “We believe that one group attacking and consuming another serves as a humiliating statement,” states Merseydus.

“The thoroughness of the body’s treatment and consumption is remarkable.” Paul Pettitt from Durham University, UK, comments, “The aggressive nature shown in these artifacts, regardless of whether the consumed were relatives or adversaries, mirrors a dehumanization process during consumption.”

Sylvia Bello from the Museum of Natural History in London concurs that this evidence of death likely ties back to conflicts but remains skeptical about the notion of consumption as humiliation. She suggests that cannibalism may stem from aggression and animosity rather than ritualized farewell practices, implying a more complex interpretation. “It could carry ritual significance, even amid warfare,” she asserts.

Neanderthals, Ancient Humans, and Cave Art in France

Join new scientist Kate Douglas on an enthralling exploration of the key Neanderthal and Upper Paleolithic sites in southern France, spanning from Bordeaux to Montpellier.

Topic:

Source: www.newscientist.com

Pharmacological potential discovered in toxins found in crustacean venom from Mayan underwater caves

Xibalbanus turmensisThe poisonous remipede, found in the caves of Antiarin on the Yucatan Peninsula, is the only crustacean for which a venom system has been described.

Xibalbanus turmensis. Image credit: Pinheiro-Junior others., doi: 10.1186/s12915-024-01955-5.

“Poisonous animals inject toxic compounds into other organisms primarily for self-defense or predation,” said Dr. Björn von Roymont, a researcher at Goethe University Frankfurt, and his colleagues.

“Many venoms are composed of proteins that have evolved to modulate various physiological functions in the target organism.”

“Studying these biological activities could lead to pharmacological or agrochemical applications.”

“The majority of thoroughly studied venoms and venomous proteins originate from iconic terrestrial groups, primarily snakes, spiders, scorpions, and insects,” the researchers said.

“Research attention to marine life has been limited, with only a few fish and invertebrates being better studied, such as sea anemones, jellyfish, cone snails, cephalopods, polychaetes, and more recently nemertes.”

“Venoms and their toxic proteins have evolved independently in different animal lineages, so the study of new lineages provides an opportunity to identify novel toxic compounds with interesting biological activities, on the one hand, and generally convergent proteins on the other hand. It provides an opportunity to improve our understanding of the evolution of functional traits.”

In their study, the researchers investigated the biological activity of peptides found in crustacean venom. Xibalbanus turmensis.

This underwater cave-dwelling crustacean belongs to the following classes: Remipediafirst described in the 1980s and currently consists of 28 extant species.

Xibalbanus turmensis They live in cenotes, underwater caves in Mexico's Yucatan Peninsula,” the scientists said.

“Cave dwellers directly inject the venom produced by their venom glands into their prey.”

“This toxin contains a variety of components, including a new type of peptide named cibalbin after the crustacean producer.”

“Some of these sibalbins contain characteristic structural elements that are well known to other toxins, especially those produced by spiders. Some amino acids (cysteine) in the peptide are tied together like a knot. are connected to each other in such a way that they form a structure.

“This makes the peptide more resistant to enzymes, heat, and extreme pH values.”

“Such knots often act as neurotoxins, interacting with ion channels to paralyze prey. This effect has also been proposed for some cibalbins.”

This study shows that all sibalbin peptides tested by the team, particularly Xib1, Xib2, and Xib13, effectively inhibit potassium channels in mammalian systems.

“This inhibition is very important when developing drugs to treat a variety of neurological diseases, including epilepsy,” Dr. von Roymont said.

“Xib1 and Xib13 also exhibit the ability to inhibit voltage-gated sodium channels, such as those found in neurons and cardiomyocytes.”

“Furthermore, in higher mammalian sensory neurons, the two peptides can activate two proteins involved in signal transduction: the kinases PKA-II and ERK1/2.”

“The latter suggests that they are involved in pain sensitization, opening the door to new approaches in pain treatment.”

of the team findings Published in a magazine BMC biology.

_____

EL Pinheiro – Junior others. 2024. Xibalbin mutants divergently evolved from remipede toxin inhibit potassium channels and activate PKA-II and Erk1/2 signaling. BMC biol 22, 164; doi: 10.1186/s12915-024-01955-5

Source: www.sci.news

There are caves on the moon that scientists believe could be used as shelters

Caves on the moon have been identified by scientists not too far from where Neil Armstrong and Buzz Aldrin landed 55 years ago. They speculate that there could be hundreds more caves that could be suitable for future astronauts to inhabit.

A team of researchers led by Italians reported on Monday that they have evidence of a large cavern accessible through the deepest hole on the moon’s surface. This cavern is situated in Mare Tranquility, just 250 miles (400 kilometers) from the Apollo 11 landing site.

The hole, like over 200 others found in that area, was created by the collapse of a lava tube.

The researchers examined radar measurements from NASA’s lunar rover and compared their findings to lava tubes on Earth. Their findings were published in the journal Nature Astronomy.

Scientists state that the radar data has only uncovered the initial section of the underground chamber, which they estimate to be at least 130 feet (40 meters) wide and potentially even longer.

Leonardo Carrell and Lorenzo Bruzzone from the University of Trento expressed their excitement in an email saying, “The lunar caves have remained a mystery for more than 50 years, so it’s exciting to finally be able to prove their existence.”

Most of the holes on the moon seem to be situated in the ancient lava plains, and there might also be caves at the moon’s south pole, where NASA intends to send astronauts in 10 years. A crater in perpetual shadow there is believed to contain frozen water that could be used for drinking or as rocket fuel.

NASA’s Apollo program successfully landed 12 astronauts on the moon, starting with Armstrong and Aldrin on July 20, 1969.

These findings suggest that the Moon could have numerous caves and lava tubes, providing natural shelter for astronauts and shielding them from cosmic rays, solar radiation, and micrometeorite impacts. Constructing habitats from scratch would be more time-consuming and challenging, even if cave walls need reinforcement to prevent collapse.

The rocks and other materials in these caves, unaffected by the harsh surface conditions for hundreds of millions of years, could also help scientists gain a better understanding of how the Moon evolved, especially in terms of its volcanic activity.

Source: www.nbcnews.com

Archaeologists uncover ancient human occupation of Saudi Arabia’s lava tube caves spanning 7,000 years

New archaeological excavations show that the Umm Jirsan lava tubes in Halat Khyber, northwestern Saudi Arabia, have been repeatedly visited by humans from at least the Neolithic period to the Chalcolithic/Bronze Age (10,000 to 3,500 years ago). The stage of residence has become clear.

Photos of Umm Jilsan Cave and its interior.Image credit: Stewart other., doi: 10.1371/journal.pone.0299292.

Intensified field research in northern Arabia over the past decade has highlighted the richness and diversity of the region's archaeological and paleontological record.

Human settlement in northern Arabia during the Pleistocene appeared to be sporadic and associated with periods of improved climate, but by the Holocene people had settled in the area more consistently through dry periods. I was able to.

“Our discoveries at Umm Jilsan provide a rare glimpse into the lives of the ancient peoples of Arabia, revealing repeated stages of human occupation and the pastoralism that once flourished here. It sheds light on people's activities,” said Griffith archaeologist Dr Matthew Stewart. University and the Max Planck Institute for Geoanthropology.

“This site probably served as an important transit point along pastoral routes, linking major oases and facilitating cultural exchange and trade.”

Rock art and animal records attest to the pastoral use of Umm Jilsan and the surrounding area, providing a vivid picture of an ancient way of life.

Depictions of cows, sheep, goats, and dogs confirm prehistoric livestock practices and herd composition in the area.

Isotope analysis of animal remains collected from lava tubes shows that livestock primarily grazed wildflowers and shrubs, while humans maintained a protein-rich diet and increased their consumption of C3 plants over time. has increased significantly, suggesting the emergence of oasis agriculture.

Professor Michael Petraglia, an archaeologist from Griffith University, the University of Queensland, and the Smithsonian Institution, said: “Subterranean localities are of global importance in archeology and Quaternary science, but our research is the first of its kind in Saudi Arabia. “This is the first comprehensive study.”

This discovery highlights the immense potential of interdisciplinary research in caves and lava tubes, providing a unique window into Arabia's ancient past.

“Umm Jilsan was probably not a permanent settlement, but a valuable transit point for people traveling between oasis settlements,” the authors said.

“Lava tubes and other natural shelters are valuable resources for communities surviving in difficult environments, and further research shows that they are important archaeological sources of information about the history of human occupation in Arabia. ”

“Our research into Arabia's hidden past uncovers thousands of years of human habitation in and around the Umm Jirsan lava tubes, revealing ancient lifestyles and environmental changes in this harsh desert environment. shed light on the adaptation of

team's paper Published in an online journal PLoS ONE.

_____

M. Stewart other. 2024. First evidence of human occupation of Arabia's lava tubes: Archeology of Umm Jirsan Cave and Surroundings, Northern Saudi Arabia. PLoS ONE 19 (4): e0299292; doi: 10.1371/journal.pone.0299292

Source: www.sci.news