Luca is the progenitor of all life on Earth. But its genesis has implications far beyond our planet.  New research into the single-celled organism is providing clues about what the early planet looked like – and raising the prospect that we may not be alone in the universe Guardian Philip Ball  Sun 19 Jan 2025 For scientists, our earliest ancestor wasn’t Adam or Eve but Luca. Luca didn’t look anything like us – it was a single-celled bacterium-like organism. A recent study by a team of scientists based in the UK has delivered rather shocking news about this illustrious forebear. Despite having lived almost as far back as seems possible, Luca was surprisingly similar to modern bacteria – and what’s more, it apparently lived in a thriving community of other organisms that have left no trace on Earth today.

Luca – short for the last universal common ancestor, the progenitor of all known life on Earth – seems to have been born 4.2bn years ago. Back then our planet was no Eden but something of a hell on Earth: a seething mass of volcanoes pummeled by giant meteorites, and having recovered from a cosmic collision that blasted the world apart and created the moon from some of the fragments. There is a good reason why the geological aeon before 4bn years ago is called the Hadean, after the Greek god of the underworld Hades. If Luca really was so ancient, yet already so sophisticated and embedded in a whole ecosystem, there’s a startling implication that goes far beyond an understanding of our own origins. It suggests that life must have got started on Earth pretty much as soon as it possibly could have done. Which in turn implies that, given the right conditions and ingredients, life might not be an extremely rare and unlikely accident, as some scientists have believed, but rather, almost an inevitability, and therefore likely to be abundant in the universe. Earth was spinning faster on its axis, so the days were 12 hours long. The moon was closer than it is now, so the tides were stronger Rika Anderson, microbiologist Luca’s existence is a corollary of Darwinian evolutionary theory, whereby all living organisms from microbes to whales descended from earlier ones in one vast tree of life. We humans share a common ancestor with chimpanzees and bonobos that lived about 6-8m years ago. All monkeys and apes are thought to have branched from a common ancestor about 25m years ago. Keep going back down the tree far enough and you will find a common ancestor of all mammals, then all vertebrate organisms, and so on. Luca represents the point where the three domains of all life – eukarya (including animals, plants and fungi), bacteria, and archaea (another kind of microbe) – converge to a single stem. When this happened has been the subject of debate for decades. Luca was once thought to have lived about 3.5-3.8bn years ago, comfortably outside the Hadean. But recent studies have pushed it ever further back in timeIt might seem unlikely that we could know anything at all about Luca. 

There are no fossil records of life that old, and very few rocks remain unchanged from that time to hold clues about what the Earth was like. But scientists can make deductions about such early organisms using the technique of molecular phylogenetics. By comparing the genetic sequences of organisms alive today, they can figure out from their similarities and differences the order in which the various species split off as separate branches of the evolutionary tree, as well as what genes their common ancestors might have possessed. And if they know the rate at which mutations in genes create such differences, this provides a “molecular clock” that can furnish estimates of when the branching happened. Stretching such analyses all the way back to Luca on the very early Earth, based only on genetic information about organisms alive today, is a tall order. The reconstructed genomes of such ancient ancestral organisms are simply best guesses, and patchy even then. That’s why the age and the nature of Luca have been contentious. But the task becomes more reliable as we gather ever more genetic information about modern organisms. ast July, a team led by researchers at Bristol University reported on a state-of-the-art molecular phylogenetic study that pointed to the conclusion that Luca lived 4.2bn years ago, give or take 100m years. That’s within the range, but towards the most ancient end, of some earlier estimates.

This Hadean Earth had no breathable air: oxygen today is produced by photosynthesis by plants and bacteria, which began much later. The atmosphere contained lots of carbon dioxide, says Earth system scientist Tim Lenton of Exeter University, a co-author of the new study – and as a result, “the sky may have been less blue than it is today”. It might even have had an orange hint from a haze of methane. Earth was then a water world, covered entirely in ocean with just a few volcanic islands poking above the waves. What’s more, says marine microbiologist Rika Anderson of Carleton College in Northfield, Minnesota, “the Earth was spinning faster on its axis, so days were 12 hours long. And the moon was closer than it is now, so tides were stronger.”

How did Luca sustain itself? The phylogenetic analysis shows that it had all the molecular machinery – the protein enzymes – it needed to feed itself from simple molecules in its surroundings, specifically carbon dioxide and hydrogen. Living at the sea surface, it could have got both of those from the atmosphere. Alternatively, Luca could have gleaned them from so-called hydrothermal vents in the deep sea, where volcanic heat sends hot water within fissures in the rock streaming out of chimney-like geological formations, enriched in minerals and dissolved gases. Some researchers think that life itself began at such deep vents, protected from the scourge of meteorite bombardment.That would make Luca a chemoautotroph: an organism able to make the chemicals it needs from simple ones formed in geological processes. But it could also have been a heterotroph, dependent on chemicals made in metabolic reactions by other organisms in the ecosystem. At any rate, the new study shows that Luca had quite a complex set of metabolic enzyme machinery: it wasn’t a rough first draft of life, but already a pretty sophisticated and refined piece of work, suggesting that it had already been evolving for ages. Luca’s ecosystem might have induced more diversity than could have arisen by conventional Darwinian evolution

Luca probably “did not live alone”, says Lenton. By making complex organic molecules, it would have created an environment where other heterotrophic organisms could thrive, perhaps some by gobbling up Luca itself. “It would have created niches for other bugs to make a living based on its waste products,” says palaeobiologist Philip Donoghue, one of the leaders of the Bristol team. The researchers think Luca’s neighbours might have included organisms that, like many microbes today (including those in the gut), generated methane (CH4), thereby returning carbon and hydrogen into the atmosphere. “That creates a recycling loop that makes everyone more productive,” says Lenton. If Luca did indeed live at a vent, says Anderson, some members of its community might have used sulphur or iron in the vent fluids as their fuel. A recent study by researchers at the University of Arizona in Tucson supports that idea, finding that sulphur-containing and metal-binding amino acids were among the first to be used by Luca and its ancestors for making proteins.     Some bacteria today have a defence system called CRISPR-Cas, which can stitch pieces of viral genomes into the DNA of the host, creating a molecular memory of past infection to accelerate a defensive response, much as our own immune systems do.

Luca’s reconstructed genome seems to include instructions for a CRISPR-Cas-like apparatus, suggesting that viruses were rife – and a potential problem – in its ecosystem. This is perhaps no surprise, for some researchers now believe that viruses – parasites that hijack the machinery of their host cells to replicate themselves – are an inevitable outcome of how life works by DNA replication. “I tend to think of viruses as being universal to life,” says Anderson. But she adds that she does not imagine viruses back then looked like viruses today, “so I was a little surprised to see that a CRISPR system existed in Luca”. It’s a sophisticated bit of kit for such an ancient organism......fascinating stuff- read on         

https://www.theguardian.com/science/2025/jan/19/luca-is-the-progenitor-of-all-life-on-earth-but-its-genesis-has-implications-far-beyond-our-planet

• Squid-bone sponge found to soak up 99.8 percent of microplastics. Dezeen Rima Sabina Aouf 12-18-204

   A sponge made from a fusion of cotton fibre and squid bone could help to clear some of the world's microplastic pollution after a team of Chinese researchers found it can soak up as much as 99.8 per cent of the particles from water samples. Researchers from the University of Wuhan and Guangxi University produced the fibrous foam by combining cellulose fibres from cotton and the tough biopolymer chitin, which forms a squid's skeleton.When deployed in water, the sponge was found to remove between 98 and 99.8 per cent of microplastics, and the researchers believe the material's low cost and simple production could allow it to be scaled up for widespread use.                                                                                             
• "Few practical technologies" for removal of microplastics - Cellulose and chitin are two very abundant molecules in nature and are already often used to help cleanse pollutants from wastewater. The researchers' innovation involved combining the two in a way that offers unprecedented efficacy at cleaning up microplastics – the tiny plastic particles that have pervaded the environment, posing a significant risk to ecosystems and human health. "The planet is under great threat from microplastics," the researchers wrote in their paper in the journal Science Advances. "And aquatic ecosystems are the first to suffer as they provide convenient places for microplastics, which can combine with other contaminants and be ingested by multiple levels of organisms.
• "Currently, there are few practical technologies for efficient and extensive removal of microplastics, especially for those smaller than 10 [micrometres]." Although the cellulose and chitin are fused on a molecular level to make the "Ct-Cel biomass foam", the production process was completed using readily available equipment. The researchers say that this – combined with the low cost of the abundant materials and their non-toxic, biocompatible nature – means that the foam could avoid the problems that have hampered other solutions from gaining traction outside of the lab."These works generally involved complex fabrication procedures or expensive raw materials, and the investment might be unaffordable for large-scale remediation of microplastics," they wrote. Biomass sponge is made simply and cheaply....read on
• https://www.dezeen.com/2024/12/18/squid-bone-sponge-microplastics-university-wuhan-technology/?utm_medium=email&utm_campaign=Daily%20Dezeen&utm_content=Daily%20Dezeen+CID_cced781ad54b3b7fcb96478f0c1a1c1d&utm_source=Dezeen%20Mail&utm_term=Squid-bone%20sponge%20found%20to%20soak%20up%20998%20per%20cent%20of%20microplastics

The innovation turning desert sand into farmland BBC News  Aamir Rafiq Peerzada 16-5-2018 Faisal Mohammed Al Shimmari Farms are in some of the most extreme conditions in the world, at Al Ain, an oasis in the United Arab Emirates desert, where temperatures can reach 50C. "It's expensive as we have to buy water regularly to irrigate these plants," he says. Farmers have to use tankers to bring in water, and in the desert farms use almost three times as much water as those in temperate climates. This makes farming in the desert impractical so the UAE imports about 80% of its food. Yet for many, this might be the future of farming. Increased drought, deforestation and intensive farming methods are turning an area half the si ze of Britain into desert each year. According to the United Nations, by 2030, 135 million people could lose their homes and livelihoods to desertification. That raises the challenge of how to grow food in increasingly hostile conditions, but one scientist has come up with an innovation that could turn those deserts green again.

This Platform Could Change Carbon Capture Forever: PrISMa Overcomes the “Valley of Death”

Pioneering Solutions.....Now, a team of scientists from Heriot-Watt University is behind a pioneering platform named PrISMa (Process-Informed design of tailor-made Sorbent Materials) which uses advanced simulations and machine learning to find the most cost-effective and sustainable material-capture process combinations prior to implementation. The platform and its associated research were published recently in the internationally renowned journal, Nature. Professor Susana Garcia led the study and is the project coordinator for PrISMa. She is also the Associate Director of Carbon Capture, Utilisation and Storage (CCUS) at the Research Centre for Carbon Solutions (RCCS) at Heriot-Watt University in Edinburgh, Scotland. She explains: “Over the past decade, there has been a huge amount of effort devoted to identifying promising materials capable of capturing CO₂.

“Chemists have proposed thousands of novel porous materials, but we did not have the tools to quickly evaluate if any materials are promising for a carbon capture process. Evaluating such materials requires a lot of experimental data and detailed knowledge of the capture process. And a careful evaluation of the economics and life-cycle assessment of the process. “We cannot expect chemists to have all that knowledge. Here is where PrISMa can make a huge difference. The PrISMa platform is a modeling tool that integrates different aspects of carbon capture, including materials, process design, economic analysis, and life cycle assessment. We use quantum chemistry, molecular simulation, and Machine Learning to predict, for new materials, all the data that is needed to design a process. Alternatively, we can use the experimental data from materials synthesized in a lab. The platform then evaluated their performance in over 60 different case studies from around the world.” Professor Garcia continues: “This innovative approach accelerates the discovery of top-performing materials for carbon capture, surpassing traditional trial-and-error methods. The platform can also inform the different stakeholders by providing engineers with options to identify economically and environmentally challenging factors in the design phase of optimal capture technologies, molecular design targets for chemists and environmental hotspots for materials, local integration benefits for CO₂ producers, and the best locations for investors.”..........read on    https://scitechdaily.com/this-platform-could-change-carbon-capture-forever-prisma-overcomes-the-valley-of-death/