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‘Ingredients for life’ discovered in 3.5b-year-old rocks in Australia
Researchers have discovered organic molecules trapped in incredibly ancient rock formations in Australia, revealing what they say is the first detailed evidence of early chemical ingredients that could have underpinned Earth’s primeval microbial life-forms.
The discovery, made in the 3.5-billion-year-old Dresser Formation of Western Australia’s Pilbara Craton, adds to a significant body of research pointing to ancient life in this part of the world – which represents one of only two pristine, exposed deposits of land on Earth dating back to the Archean Eon, sciencealert.com reported.
In recent years, the hydrothermal rock of the Dresser Formation has turned up repeated signals of what looks to be the earliest known life on land, with scientists discovering “definitive evidence” of microbial biosignatures dating back to 3.5 billion years ago.
Now, in a new study, researchers in Germany have identified traces of specific chemistry that could have enabled such primordial organisms to exist, finding biologically relevant organic molecules contained inside barite deposits, a mineral formed through various processes, including hydrothermal phenomena.
“In the field, the barites are directly associated with fossilized microbial mats, and they smell like rotten eggs when freshly scratched,” explains geobiologist Helge Mißbach from the University of Cologne in Germany.
“Thus, we suspected that they contained organic material that might have served as nutrients for early microbial life.”
While scientists have long hypothesized about how organic molecules could act as substrates for primeval microbes and their metabolic processes, direct evidence has to date proven largely elusive.
To investigate, Mißbach and fellow researchers examined inclusions within barites from the Dresser Formation, with the chemically stable mineral capable of preserving fluids and gases inside the rock for billions of years.
Using a range of techniques to analyze the barite samples – including gas chromatography-mass spectrometry, microthermometry, and stable isotope analysis, the researchers found what they describe as an “intriguing diversity of organic molecules with known or inferred metabolic relevance.”
Among these were the organic compounds acetic acid and methanethiol, in addition to numerous gases, including hydrogen sulfide, that could have had biotic or abiotic origins.
While it may be impossible to be sure of the precise links, the close proximity of these inclusions within the barite rock and adjacent organic accretions called stromatolites suggests that the ancient chemicals, once carried inside hydrothermal fluids, may have influenced primeval microbial communities.
“Indeed, many compounds discovered in the barite-hosted fluid inclusions … would have provided ideal substrates for the sulfur-based and methanogenic microbes previously proposed as players in the Dresser environment,” the researchers write in their study.
In addition to chemicals that may have acted as nutrients or substrates, other compounds found within the inclusions may have served as ‘building blocks’ for various carbon-based chemical reactions – processes that could have kick-started microbial metabolism, by producing energy sources, such as lipids, that could be broken down by life-forms.
“In other words, essential ingredients of methyl thioacetate, a proposed critical agent in the emergence of life, were available in the Dresser environments,” the team explains.
“They might have conveyed the building blocks for chemoautotrophic carbon fixation and, thus, anabolic uptake of carbon into biomass.”
The findings are reported in Nature Communications.
Climate change to blame for worsening allergy seasons
If you live with seasonal allergies and feel like the pollen seasons feel longer and longer every year, you may be right. New research shows that pollen seasons start 20 days earlier, are 10 days longer, and feature 21 percent more pollen than in 1990 – meaning more days of itchy, sneezy, drippy misery.
Led by William Anderegg of the University of Utah School of Biological Sciences, the researchers found that human-caused climate change played a significant role in pollen season lengthening and a partial role in pollen amount increasing. Their research is published in Proceedings of the National Academy of Sciences, scitechdaily.com reported.
“The strong link between warmer weather and pollen seasons provides a crystal-clear example of how climate change is already affecting peoples’ health across the US,” says Anderegg.
Pollen matters
Allergies to airborne pollen can be more than just a seasonal nuisance to many. Allergies are tied to respiratory health, with implications for viral infections, emergency room visits and even children’s school performance. More pollen, hanging around for a longer season, makes those impacts worse.
Although previous studies found that increases in temperature and atmospheric carbon dioxide – hallmarks of human-caused climate change – can cause more pollen production in greenhouse experiments, and that small-scale studies show worsening of pollen seasons in some locations or in some plants correlated with temperature, scientists hadn’t yet looked at pollen trends at a continental scale or calculated the likely contribution of climate change. That’s exactly what Anderegg and his colleagues set out to do.
“A number of smaller-scale studies – usually in greenhouse settings on small plants – had indicated strong links between temperature and pollen,” Anderegg notes. “This study reveals that connection at continental scales and explicitly links pollen trends to human-caused climate change.”
The team compiled measurements between 1990 and 2018 from 60 pollen count stations across the United States and Canada, maintained by the National Allergy Bureau. These stations collect airborne pollen and mold samples, which are then hand-counted by certified counters.
Although nationwide pollen amounts in the US increased by around 21 percent over the study period, the greatest increases were recorded in Texas and the Midwestern US, and more among tree pollen than among other plants.
Pollen seasons today start around 20 days earlier than in 1990, suggesting that warming is causing the plants’ internal timing (also called its phenology) to start producing pollen earlier in the year.
What’s climate change got to do with it?
But can we say that the changes in pollen are a result of climate change? The researchers answered that question by applying statistical methods to the pollen trends in conjunction with nearly two dozen climate models.
The results showed that climate change alone could account for around half of the pollen season lengthening and around 8 percent of the pollen amount increasing. By splitting the study years into two periods, 1990-2003 and 2003-2018, the researchers found that the contribution of climate change to increasing pollen amounts is accelerating.
“Climate change isn’t something far away and in the future. It’s already here in every spring breath we take and increasing human misery,” says Anderegg. “The biggest question is – are we up to the challenge of tackling it?”
Pioneering research reveals gardens are secret powerhouse for pollinators
Home gardens are by far the biggest source of food for pollinating insects, including bees and wasps, in cities and towns, according to new research.
The study, led by the University of Bristol and published in the Journal of Ecology, measured for the first time how much nectar is produced in urban areas and discovered residential gardens accounted for the vast majority – some 85 percent on average, phys.org reported.
Results showed three gardens generated daily on average around a teaspoon of Nature’s ambrosia, the unique sugar-rich liquid found in flowers which pollinators drink for energy. While a teaspoon may not sound much to humans, it’s the equivalent to more than a ton to an adult human and enough to fuel thousands of flying bees. The more bees and fellow pollinators can fly, the greater diversity of flora and fauna will be maintained.
Ecologist Nicholas Tew, lead author of the study, said, “Although the quantity and diversity of nectar has been measured in the countryside, this wasn’t the case in urban areas, so we decided to investigate.
“We expected private gardens in towns and cities to be a plentiful source of nectar, but didn’t anticipate the scale of production would be to such an overwhelming extent. Our findings highlight the pivotal role they play in supporting pollinators and promoting biodiversity in urban areas across the country.”
The research, carried out in partnership with the universities of Edinburgh and Reading and the Royal Horticultural Society, examined the nectar production in four major UK towns and cities: Bristol, Edinburgh, Leeds, and Reading.
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Sustainable energy key to COVID recovery in Asia and the Pacific
By Armida Salsiah Alisjahbana*
The past year is one that few of us will forget. While the impacts of the COVID-19 pandemic have played out unevenly across Asia and the Pacific, the region has been spared many of the worst effects seen in other parts of the world. The pandemic has reminded us that a reliable and uninterrupted energy supply is critical to managing this crisis.
Beyond ensuring that hospitals and healthcare facilities continue to function, energy supports the systems and coping mechanisms we rely on to work remotely, undertake distance learning and communicate essential health information. Importantly, energy will also underpin cold chains and logistics to ensure that billions of vaccines make their way to the people who need them most.
The good news is our region’s energy systems have continued to function throughout the pandemic. A new report Shaping a sustainable energy future in Asia and the Pacific: A greener, more resilient and inclusive energy system released today by the United Nations Economic and Social Commission for Asia and the Pacific (ESCAP) shows the energy demand reductions have mainly impacted fossil fuels and depressed oil and gas prices. Renewable energy development in countries across the region, such as China and India, has continued at a healthy pace throughout 2020.
As the Asia-Pacific region transitions its energy system to clean, efficient and low carbon technologies, the emergence of the pandemic raises some fundamental questions. How can a transformed energy system help ensure our resilience to future crises such as COVID-19? As we recover from this pandemic, can we launch a “green recovery” that simultaneously rebuilds our economies and puts us on track to meet global climate and sustainability goals?
A clean and sustainable energy is central to a recovery from COVID-19 pandemic. By emphasizing the importance of the SDGs as a guiding framework for recovering better together, we must focus on two critical aspects:
First, by making meaningful progress on the SDGs, we can address many of the systemic issues that made societies more vulnerable to COVID-19 in the first place – health, decent work, poverty and inequalities, to name a few.
Second, by directing stimulus spending to investments that support the achievement of the SDGs, we can build back better. If countries focus their stimulus efforts on the industries of the past such as fossil fuels, we risk not creating the jobs we need, or moving in the right direction to achieve the global goals that are critical to future generations. The energy sector offers multiple opportunities to align stimulus with the clean industries of the future.
The evidence shows that renewable energy and energy efficiency projects create more jobs for the same investment as fossil fuel projects. By increasing expenditure on clean cooking and electricity access, we can enhance economic activity in rural areas and bring modern infrastructure that can make these communities more resilient and inclusive, particularly for the wellbeing of women and children.
Additionally, investing in low-carbon infrastructure and technologies can create a basis for the more ambitious climate pledges we need to reach the Paris Agreement targets of a 2-degree global warming limit. On this note, several countries have announced carbon neutrality, demonstrating a long-term vision and commitment to an accelerated transformation to sustainable energy. Phasing out the use of coal from power generation portfolios by substituting with renewables, ending fossil fuel subsidies, and implementing carbon pricing are some of the steps we can take.
The COVID-19 crisis has forced us to change many aspects of our lives to keep ourselves and our societies safe. It has shown that we are more adaptive and resilient than we may have believed. Nevertheless, we should not waste the opportunities this crisis presents for transformative change. It should not deflect us from the urgent task of making modern energy available to all and decarbonizing the region’s energy system through a transition to sustainable energy. Instead, it should provide us with a renewed sense of urgency.
We must harness the capacity of sustainable energy to rebuild our societies and economies while protecting the environment in the pursuit of the 2030 Agenda for Sustainable Development.
* Armida Salsiah Alisjahbana is undersecretary-general of the United Nations and executive secretary of the UN Economic and Social Commission for Asia and the Pacific (ESCAP).
Source: UNIC-Tehran
Lethal food for flamingos
Conservationists in Cyprus are urging authorities to expand a hunting ban throughout a coastal salt lake network, amid concerns that migrating flamingos could swallow lethal quantities of lead shotgun pellets, the Guardian reported.
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