In years with ample precipitation, winter snow that accumulates in the Mogollon Mountains and Black Range provides much of the river’s spring runoff. That water helps replenish San Carlos Reservoir, which was created by the Coolidge Dam. When full, the reservoir ranks among Arizona’s largest lakes.

Snowpack Collapse Drains the Reservoir

Conditions were dramatically different in 2026. Snowfall in the Gila River watershed was exceptionally scarce, leaving mountain snowpack at just 2 percent of the 1991-2020 March median. As a result, streamflow during April reached only 39 percent of normal levels.

By June, required releases of water for downstream agricultural use had further reduced supplies. The reservoir contained less than 400 acre-feet of water.

A comparison of Landsat satellite images highlights the dramatic change. The image above (right), captured on May 22, 2026, shows San Carlos Reservoir holding only 389 acre-feet of water, making it less than 1 percent full. By contrast, the image on the left, taken in June 2023, shows the reservoir at roughly 60 percent capacity. Vegetation visible along the reservoir shoreline and river channel includes tamarisk, willow, cottonwood, sedges, and various grasses.

Massive Fish Kill Forces Closure

As water levels continued to fall, oxygen levels in the reservoir dropped sharply. The resulting hypoxia killed virtually all of the fish living there.

Officials responded by closing the reservoir indefinitely on June 5, 2026. Fish species affected included largemouth bass, black crappie, bluegill, channel catfish, flathead catfish, and stocked species such as brown trout and rainbow trout.

The San Carlos Recreation and Wildlife Department also warned that decomposing fish could create health risks for people attempting to fish or boat in the area.

A Long History of Extreme Low Water

Although the current situation is severe, it is not without precedent. News reports indicate that San Carlos Reservoir has completely run dry at least 20 times since it first filled in 1930.

Even during the original dedication of the dam and reservoir, conditions were dry enough for grass to grow across exposed lakebed. Humorist Will Rogers famously joked to President Calvin Coolidge: “If that was my lake, I’d mow it.”

Major fish kills have occurred before as well, including in 1976 and 2018. According to the Gila Herald, a fish kill in 1976 claimed more than 5 million fish, and the reservoir’s ecosystem required five years to recover.

Drought Continues but Rain Could Bring Relief

The region remains locked in a multi-year dry spell. Data from the U.S. Drought Monitor show that much of the Gila River’s headwaters in New Mexico is currently experiencing severe drought.

Still, the river’s flow can vary dramatically from year to year. Significant rainfall during the upcoming wet season could help replenish the reservoir.

A NOAA seasonal monsoon outlook issued in May 2026 estimated a 33 to 50 percent chance of above-average rainfall across the region during the summer. At the same time, El Niño conditions in the central and eastern equatorial Pacific were strengthening during late spring 2026, a pattern that can increase the likelihood of heavy rainfall across the U.S. Southwest.

The findings were published today in Environmental Research Letters by Kevin Gurney, a professor in NAU’s School of Informatics, Computing, and Cyber Systems (SICCS). The study focused on carbon dioxide (CO₂) emissions from cars and trucks reported in the recently released Climate TRACE database.

Gurney said the results, together with an earlier study that identified similar issues in Climate TRACE estimates for power plants, raise concerns about the reliability of emissions data used to guide climate policy and decision-making.

“Given the importance of vehicle CO₂ emissions in cities, we carefully examined the Climate TRACE data which relied on promising new artificial intelligence-based approaches,” Gurney said. “When combined with our previous study on Climate TRACE power plant CO₂ emissions, our results suggest that the Climate TRACE data significantly underestimate over half of U.S. fossil fuel-based CO₂ emissions in cities.”

Comparing Climate TRACE to the Vulcan Emissions Database

To evaluate the Climate TRACE estimates, Gurney and his colleagues compared them with data from Vulcan, an “onroad” emissions database developed by his laboratory. The Vulcan system is calibrated using official traffic records and energy consumption data, providing an independent benchmark for measuring vehicle emissions.

The researchers compared vehicle CO₂ emissions data from 260 U.S. cities across the two databases.

“While the Vulcan onroad data is not perfect, with uncertainty of about 14%, this is far lower than the differences found when we compared 260 city vehicle CO₂ emissions in the U.S. to the Climate TRACE database,” said Bilal Aslam, a SICCS postdoc and co-investigator on the study. “The Climate TRACE CO₂ emissions were, on average, 70% lower than those same emissions in the Vulcan onroad CO₂ emissions database.”

According to the researchers, the discrepancies were even larger in some locations.

“Individual cities such as Indianapolis and Nashville were lower by more than 90%,” added Pawlok Dass, a research associate in SICCS and contributor to the study.

The authors believe the underestimation may extend beyond the United States and could affect Climate TRACE data globally. They also expressed concerns about other aspects of the database that may warrant additional scrutiny.

Concerns About AI-Based Emissions Tracking

The researchers emphasized that artificial intelligence has enormous potential for monitoring environmental conditions and generating emissions estimates. However, they argue that strong scientific standards remain essential.

In their view, transparency, expert review, and rigorous scientific methods are necessary to ensure that emissions data are accurate and trustworthy. Reliable greenhouse gas measurements are a fundamental part of creating effective climate policies and evaluating progress toward emissions reductions.

The paper also outlines several recommendations intended to strengthen and improve Climate TRACE’s work, helping policymakers and budget planners make better-informed decisions about reducing greenhouse gas emissions.

“We will never estimate emissions with perfect accuracy, but we must ensure that the data shared with policymakers and the public is unbiased and meets best practices and the most rigorous scientific standards available,” Gurney said. “Without this, we mislead decision makers and potentially lose public trust in our ability to tackle climate change.”

Kevin Gurney’s Work on Greenhouse Gas Emissions

Gurney, whose expertise spans atmospheric science, ecology and public policy, has spent more than 20 years developing standardized approaches for measuring greenhouse gas emissions across the United States.

His Vulcan and Hestia projects, supported by multiple federal agencies, quantify and visualize greenhouse gas emissions nationwide, from individual power plants and roadways to neighborhoods. These systems help identify emissions “hotspots” and support more targeted strategies for reducing pollution. Gurney’s emissions estimates have also demonstrated strong agreement with direct atmospheric monitoring measurements.

Over the course of his career, Gurney has authored more than 180 scientific papers that have received more than 20,000 citations. His work includes contributions to a recent U.S. National Academy Report, “Greenhouse Gas Emissions for Decisionmaking.”

He has also participated in the United Nations Climate Change Framework Convention and the Kyoto Protocol process for more than 25 years and serves as a lead author for the Intergovernmental Panel on Climate Change (IPCC).

• A major study of 112,395 people tracked diets in remarkable detail, including the specific food additives participants consumed.
• Researchers identified eight commonly used food preservatives that were linked to a higher risk of high blood pressure or cardiovascular disease.
• The strongest associations were seen in people who consumed the largest amounts of preservatives, suggesting that greater exposure may carry greater health risks.

People who regularly consume foods containing common preservatives may face a greater risk of developing high blood pressure and cardiovascular disease, according to a new study published in the European Heart Journal.

The research was led by Dr. Mathilde Touvier, research director at INSERM (the French National Institute for Health and Medical Research), and Anaïs Hasenböhler, a PhD student. Both are members of the Nutritional Epidemiology Research Team at Université Sorbonne Paris Nord and Université Paris Cité in France.

Large Study Examined Food Preservatives and Heart Health

Food preservatives are widely used in industrially processed foods to extend shelf life and maintain product quality. Although previous laboratory and experimental studies have suggested that some of these additives could affect cardiovascular health, evidence from human populations has been limited.

Ms Hasenböhler said: “Food preservatives are used in hundreds of thousands of industrially processed foods. Experimental studies suggest that some preservative food additives may be harmful to cardiovascular health, but we have not had enough evidence on the impact of these ingredients in humans. As far as we know, this is the first study of its kind to investigate the links between a wide range of preservatives and cardiovascular health.”

The investigation was conducted as part of the ongoing NutriNet-Santé study and included 112,395 volunteers from across France. Participants reported everything they ate and drank over three-day periods every six months.

Researchers then performed detailed assessments of the ingredients in those foods and beverages, including preservative additives. Participants’ health was monitored for an average of seven to eight years to determine whether they developed high blood pressure or cardiovascular disease.

Nearly all participants were exposed to preservatives. Within the first two years of the study, 99.5% had consumed at least one food preservative.

Higher Preservative Intake Linked to Greater Health Risks

The analysis found that participants who consumed the highest amounts of non-antioxidant preservatives had a 29% greater risk of hypertension compared with those who consumed the least. They also had a 16% higher risk of cardiovascular disease, including heart attack, stroke, and angina.

People with the highest intake of antioxidant preservatives showed a 22% greater risk of hypertension.

Non-antioxidant preservatives are used to prevent the growth of microbes such as mold and bacteria. Antioxidant preservatives serve a different purpose, helping to prevent oxidation so foods do not become brown or rancid.

Eight Preservatives Associated With High Blood Pressure

Researchers also examined 17 of the most commonly consumed preservatives individually. Eight were specifically associated with a higher risk of high blood pressure:

• potassium sorbate (E202)
• potassium metabisulphite (E224)
• sodium nitrite (E250)
• ascorbic acid (E300)
• sodium ascorbate (E301)
• sodium erythorbate (E316)
• citric acid (E330)
• extracts of rosemary (E392)

Among these additives, ascorbic acid (E300) was also specifically linked to cardiovascular disease.

Researchers Call for Further Evaluation

Dr. Touvier added: “This study has some limitations inherent to its observational design. However, the findings are based on highly detailed data, and we have taken account of other factors that can increase or lower the risk of cardiovascular disease. Experimental research in the literature consistently suggested that preservatives may cause oxidative stress in the body or affect the way the pancreas works.

“These results suggest we need a re-evaluation of the risks and benefits of these food additives by the authorities in charge, such as the EFSA in Europe and the FDA in the USA, for better consumer protection. In the meantime, these findings support existing recommendations to favor non-processed and minimally processed foods, and avoid unnecessary additives. Doctors and other healthcare professionals play a key role in explaining these recommendations to the public.”

The research team is continuing to investigate how food additives and ultra-processed foods influence inflammation, oxidative stress, blood metabolic markers, and the composition of the gut microbiota. These studies may help explain the biological mechanisms that could connect food additives to an increased risk of disease.

New research from the Texas A&M College of Veterinary Medicine and Biomedical Sciences (VMBS), however, suggests that regenerative abilities may not be entirely absent in mammals. Instead, they could be hidden within the body’s normal healing machinery, waiting to be activated under the right conditions.

“Why some animals can regenerate and others, particularly humans, can’t is a big question that has been asked since Aristotle,” said Dr. Ken Muneoka, a professor in the VMBS’ Department of Veterinary Physiology & Pharmacology (VTPP). “I’ve spent my career trying to understand that.”

In a study published in Nature Communications, Muneoka and colleagues describe a new two-step treatment that enabled the regeneration of bone, joint structures, and ligaments. Although the regrown tissues were not perfect replicas of the originals, the researchers believe the approach could eventually help reduce scarring and improve tissue repair after amputations.

Redirecting Healing Away From Scar Formation

When mammals are injured, the body usually responds with fibrosis. During this process, fibroblast cells quickly close the wound and create scar tissue. While this response helps prevent infection and further damage, it also limits the body’s ability to rebuild what was lost.

Animals capable of regeneration follow a different path. In salamanders, for example, similar cells gather into a structure called a blastema, which serves as a foundation for new tissue growth.

“It’s as if these cells can move in two different directions,” Muneoka said. “They could either make a scar or make a blastema. Our research focused on redirecting the behavior of fibroblasts already present at the injury site.”

To explore whether mammalian healing could be pushed toward regeneration, the research team developed a treatment that uses two well-known growth factors in sequence.

The first step involved applying fibroblast growth factor 2 (FGF2) after the wound had already healed over. By waiting until the initial healing process was complete, the researchers allowed the body to respond normally before intervening.

According to Muneoka, the team then “changed what happens next.”

FGF2 encouraged the formation of a blastema-like structure, something that does not typically occur in mammals after this type of injury. Several days later, the researchers applied a second growth factor, bone morphogenetic protein 2 (BMP2), which prompted those cells to begin building new tissues.

“This is really a two-step process,” Muneoka said. “You first shift the cells away from scarring, and then you provide the signals that tell them what to build.”

Rethinking the Role of Stem Cells

One of the study’s most important findings is that regeneration may not require adding stem cells from outside the body, an approach commonly explored in regenerative medicine.

“You don’t have to actually get stem cells and put them back in,” Muneoka said. “They’re already there — you just need to learn how to get them to behave the way you want.”

Dr. Larry Suva, another VTPP professor involved in the study, said the results challenge long-standing assumptions about what mammalian cells are capable of doing.

“The cells that we thought to be unprogrammable, in fact are,” Suva said. “The capacity is not absent — it’s just obscured.”

The researchers also found evidence that cells can be redirected to create structures outside their usual location. This process, known as positional re-specification, is an important part of development.

In practical terms, cells that would normally help form one type of tissue can be instructed to rebuild a different structure following an injury.

Regrowing Bone, Tendons, Ligaments, and Joints

Although the regenerated tissues were not exact matches to the original anatomy, the researchers successfully restored all of the major structures that had been removed during amputation, including bone, tendon, ligament, and joint tissue.

The regenerated areas contained both skeletal components and connective tissues arranged in patterns resembling natural anatomy.

“We regenerated what you would expect to see at that level of injury,” Muneoka said. “The structures are there — just not in a perfect form.”

The findings also suggest that regeneration depends on multiple biological pathways working together. Rebuilding tissue appears to be far more complex than activating a single mechanism.

Potential Benefits for Wound Healing

While the research remains in its early stages, the scientists believe it could have practical applications long before complete regeneration becomes possible.

Rather than focusing solely on replacing missing structures, the approach may help improve healing outcomes by reducing scar formation and enhancing tissue repair.

“People should start thinking about using these signals during the healing process,” Muneoka said. “Even shifting the response slightly away from scarring could have real benefits.”

The path toward clinical testing may also be more straightforward than with many experimental therapies. BMP2 already has FDA approval for certain medical applications, and FGF2 is currently being evaluated in multiple clinical trials.

A New View of Mammalian Regeneration

The study adds to growing evidence that regeneration in mammals may not be a completely lost trait. Instead, it may be a dormant capability that normally remains inactive during healing.

“This changes the way we think about what’s possible,” Suva said. “Once you show that regeneration can be activated, it opens the door to asking entirely new questions.”

For Muneoka, those questions have driven decades of research and now have a promising new framework.

“Regenerative failure in mammals can be rescued,” he said. “Now we have a model to begin figuring out how.”

The spider was found in the Llanganates-Sangay Corridor, a region of the Ecuadorian Amazon known for its extraordinary biodiversity. During a nighttime field survey, researchers initially mistook the animal for a mushroom, highlighting just how convincing its disguise is.

A Spider With a Fungus-Like Appearance

Taczanowskia waska closely resembles the fruiting body of fungi in the genus Gibellula, which grow on spiders. The spider has elongated structures extending from its abdomen and a pale coloration that gives it the appearance of fungal growth.

Its behavior strengthens the illusion. The spider remains motionless on the undersides of leaves, the same location where Gibellula fungi are commonly found.

Researchers say this combination of appearance and behavior points to a highly specialized adaptation. By blending into its surroundings as something predators are likely to ignore, the spider may reduce its chances of being eaten. The disguise may also help it catch prey by allowing it to remain unnoticed until the right moment.

First Known Example of Its Kind

According to the study, this is the first documented case of a spider imitating a parasitic fungus that infects other spiders. Scientists say the finding offers valuable insight into how mimicry evolves and the ecological functions these adaptations can serve.

The genus Taczanowskia remains poorly understood and is considered rare. Much of its ecology is still a mystery because spiders in this group are seldom encountered in the wild.

Nadine Dupérré of the Museum of Nature Hamburg at LIB contributed to the research by examining reference specimens from scientific collections and helping classify the new species.

Citizen Science Helped Spark the Discovery

The story began with a post on the citizen science platform iNaturalist. What observers initially believed to be a mushroom was later recognized by users as a spider, prompting further scientific investigation.

The case highlights the growing role of citizen science in biodiversity research and species discovery.

“Finds like these demonstrate the value of scientific collections. They enable us to classify new species and compare them with historical specimens. Combined with international collaboration and citizen science, this opens up new opportunities for researching biodiversity,” explains Nadine Dupérré.

The discovery also serves as a reminder of how much remains unknown about life in tropical ecosystems. Scientists say it underscores both the immense biodiversity of rainforest regions and the importance of international cooperation and new sources of data in advancing our understanding of the natural world.

Researchers found that seniors with depression who took a daily probiotic alongside their regular antidepressant treatment experienced modest but meaningful improvements in depression and anxiety symptoms compared with those who received a placebo. A placebo is an inactive treatment designed to look identical to the real one.

The study was published in the Journal of the American Geriatrics Society.

Exploring the Gut-Brain Connection

Scientists have become increasingly interested in the relationship between the digestive system and the brain, often referred to as the gut-brain connection. The trillions of microbes that live in the human digestive tract, collectively known as the gut microbiome, may influence mood, behavior, and mental health through a variety of biological pathways.

Probiotics are live microorganisms that can help support a healthy balance of bacteria in the gut. Researchers have been investigating whether these microbes could potentially complement traditional treatments for conditions such as depression and anxiety.

Inside the Clinical Trial

The pilot study enrolled 58 adults in India who were at least 60 years old and had moderate depression. All participants continued receiving standard antidepressant treatment.

The volunteers were randomly assigned in a 1:1 ratio to receive either a daily probiotic supplement or a placebo for 12 weeks. Researchers then continued monitoring participants for another 12 weeks to track longer-term outcomes.

Importantly, both groups showed substantial improvement over the course of the study. However, the probiotic group experienced somewhat greater reductions in symptoms of depression and anxiety.

Measuring Mental Health and Biological Changes

To evaluate the effects of treatment, researchers used several different tools.

They assessed participants using established psychological rating scales designed to measure depression and anxiety symptoms. They also examined a biomarker known as (serum brain-derived neurotropic factor level). Brain-derived neurotrophic factor, often abbreviated as BDNF, is a protein involved in the growth, maintenance, and survival of nerve cells and is frequently studied in mental health research.

In addition, investigators analyzed participants’ gut bacteria through (fecal microbiota profiling), which allows scientists to examine the composition of microbes living in the digestive system.

Taken together, the findings suggested that probiotic therapy contributed to symptom improvement. However, the researchers did not find clear evidence that probiotics produced additional improvements in overall quality of life compared with placebo.

Encouraging Results, But More Research Needed

Because this was a relatively small pilot study, the findings should be viewed as preliminary. Larger studies will be needed to determine how much benefit probiotics may provide, which patients are most likely to respond, and whether the effects remain consistent across broader populations.

Even so, the results support the idea that probiotics could serve as a safe and biologically plausible addition to standard depression treatment.

“The results of our study are novel, and we are now planning a follow-up, larger-scale clinical trial due to the encouraging findings,” said co-corresponding author Dr. Saibal Das, MBBS, MD, DM, PhD, of the Indian Council of Medical Research — National Institute for Research in Bacterial Infections, Kolkata.

“My vision is to develop affordable healthcare solutions and make them available to the larger population for meaningful public health impact,” added co-corresponding author Abhinaba Ghosh, MBBS, MSc, PhD, a physician-neuroscientist from Tata Medical Center, Kolkata.