Why do we act selflessly, even when it costs us? This mystery has long intrigued scientists. New work from the University of Amsterdam now reframes one of biology’s most famous ideas: Hamilton’s Rule.



Published in the journal eLife, the study provides a mathematical update that reshapes how we think about altruism and cooperation.



First proposed in the 1960s, Hamilton’s Rule suggests that altruism <a href="https://www.earth.com/news/how-customer-courtesy-kindness-transforms-service-quality-and-job-satisfaction/">evolves</a> when the benefits to others, weighted by genetic relatedness, outweigh the cost to oneself. Simply put, helping relatives can improve the survival of shared genes.



But controversy has never left this idea. Some scientists have argued that Hamilton’s rule almost never holds, while others have placed it alongside natural selection as a universal principle.



<h2 class="wp-block-heading" id="h-many-rules-of-cooperation">Many rules of cooperation</h2>



The new analysis shows that Hamilton’s Rule is not a single law but part of a family of related rules. Each version applies in different situations, depending on how traits influence <a href="https://www.earth.com/news/childhood-kindness-linked-to-healthier-teen-choices/">survival</a> and reproduction.



"For years, the debate has been about whether Hamilton’s Rule is universal," said Matthijs van Veelen, the study’s author and professor at the <a href="https://www.uva.nl/en">University of Amsterdam</a>. 



"What I show is that it’s not a single rule, but is in fact many different versions that work in different situations. That means both sides of the debate were partly right."



<h2 class="wp-block-heading" id="h-cooperation-grounded-in-equations">Cooperation grounded in equations</h2>



This insight comes from the Generalized Price equation, an updated framework that reconnects evolutionary models with statistics. 



The framework shows that for every possible model of how traits influence fitness, there is a corresponding Price-like Equation. In turn, each equation yields a version of Hamilton’s Rule.



Earlier debates focused on whether Hamilton’s Rule “holds,” but the paper explains why that question is ill-posed. The real task is to ask which version of the rule fits a given case.



<h2 class="wp-block-heading" id="h-when-cooperation-gets-complicated">When cooperation gets complicated</h2>



The study highlights that actual <a href="https://www.earth.com/news/gut-bacteria-influence-our-social-behavior-and-sense-of-fairness/">social behaviors</a> in nature are rarely as simple as early models suggested. Interactions among individuals often do not add up in straightforward ways.



Instead, they involve nonlinear effects, where the impact of one individual’s action depends heavily on what others around them are doing. For example, the benefit of helping might increase when many group members cooperate at the same time, but it could disappear or even reverse when only a few cooperate.



Because of this, Hamilton’s Rule cannot always be described with a neat equation of cost versus benefit. In situations with these nonlinear dynamics, researchers need to include higher-order terms in the formula.



These extra terms account for the fact that cooperation can change its effect depending on population size, structure, or frequency of the behavior. 



Without those additions, simple cost–benefit equations may look correct on paper but fail to capture the real biological meaning behind the interaction. In other words, they can be technically true but practically useless.



<h2 class="wp-block-heading" id="h-hamilton-s-rule-strengthened">Hamilton’s Rule strengthened</h2>



Earlier, biologist David Queller had already suggested adjustments to Hamilton’s rule by incorporating non-additive effects into the framework. His approach acknowledged that cooperation does not always scale linearly and that frequency dependence matters. 



However, the new work by Matthijs van Veelen strengthens this idea by giving it a rigorous mathematical foundation. His general version of Hamilton’s Rule ensures that these extensions are not just clever tweaks but part of a consistent, statistically sound framework.



This places the study of altruism on much firmer ground, showing how cooperation can be explained across a wide range of complex social systems.



<h2 class="wp-block-heading" id="h-ending-the-altruism-debate">Ending the altruism debate</h2>



By clarifying these theoretical foundations, the study makes the decades-old question of universality obsolete. It shows that multiple Hamilton-like rules exist, all valid, but only meaningful when tied to the correct evolutionary model.



This reframing shifts research focus toward identifying which fitness model applies in each system, whether microbes in colonies, <a href="https://www.earth.com/news/bird-competition-how-warblers-share-trees-without-fighting/">birds</a> sharing food, or humans helping strangers.



The research also draws attention to how cooperation can emerge in very different ecological and genetic contexts, encouraging scientists to investigate population structures, environmental pressures, and frequency-dependent effects that shape altruistic behavior in unique ways across the living world.



<h2 class="wp-block-heading" id="h-why-hamilton-s-rule-matters">Why Hamilton’s Rule matters</h2>



The contribution is not just theoretical. It guides empirical research, making studies of cooperation clearer and more precise. By focusing on the form of the fitness function, scientists can avoid misinterpretations and identify the exact evolutionary conditions under which altruism evolves.



This approach also forces researchers to consider population structure and frequency dependence more seriously. For example, in some cases cooperation becomes beneficial only when a trait reaches a certain frequency in the population.



This frequency dependence, ignored in Hamilton’s original additive model, plays a critical role in determining whether altruism spreads.



<h2 class="wp-block-heading" id="h-mapping-evolution-s-many-paths">Mapping evolution’s many paths</h2>



"This result doesn’t just close the debate," said van Veelen. "It gives us a more powerful framework to use in the future. Cooperation is everywhere in nature, and now we have a clearer picture of the many ways evolution can produce it."



The key message is that there is no single path to cooperation. <a href="https://www.earth.com/news/discovery-evolution-not-random-can-be-predicted-pangenome-genetic-history/">Evolution</a> offers many, and with the new general framework, scientists now have the tools to map them with greater precision.



The study reminds us that science is not just about declaring universal rules but about understanding the diversity of conditions under which life evolves.



The study is published in the journal <a href="https://elifesciences.org/reviewed-preprints/105065v2" target="_blank" rel="noreferrer noopener">eLife</a>.



-----



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Why we help: The hidden math behind cooperation

Why do we act selflessly, even when it costs us? This mystery has long intrigued scientists. New work from the University of Amsterdam now reframes one of biology’s most famous ideas: Hamilton’s Rule. Published in the journal eLife, the study provides a mathematical update that reshapes how we think about altruism and cooperation. First proposed in the 1960s, Hamilton’s Rule suggests that altruism evolves when the benefits to others, weighted by genetic relatedness, outweigh the cost to oneself. Simply put, helping relatives can improve the survival of...

A new study from researchers at <a href="https://www.bcm.edu/">Baylor College of Medicine</a> has found that the pancreatic Islets of Langerhans, which produce insulin and other hormones, link overnutrition during infancy to long-lasting health issues, like diabetes, in adulthood. 

Researchers analyzed the islets of overnourished mice during the first 21 days after birth. These mice tended to gain DNA methylation tags, which are chemical modifications that alter gene expression, whereas mice that were not overnourished showed gaining these DNA methylation tags later in life.

"It's been known for several decades that mice that are overnourished during the suckling period remain overweight and will be prone to disease for their entire lives. Particularly, they have problems regulating their blood sugar levels," said corresponding author Dr. Robert A. Waterland, professor of pediatrics - nutrition at the USDA/ARS Children's Nutrition Research Center at Baylor College of Medicine and Texas Children's Hospital and of molecular and human genetics at Baylor.

People with Type-2 diabetes have displayed altered DNA methylation in their insulin-producing islets, and these alterations are understood to be linked to islet malfunction and the onset of <a href="http://www.earth.com/news/diabetes-patients-overtreated/">diabetes</a>. However, how they occur remained a mystery.

Therefore, using mice, Waterland and his colleagues investigated whether early overnutrition in infancy could change epigenetic, referring to molecular mechanisms that determine which genes are turned on and off in different cells, development in pancreatic islets. Epigenetics works by adding or removing chemical tags on specific genes to mark which ones should be used. DNA methylation is one of the better understood tags and plays an important role in overall development.

"Adjusting litter size during the suckling period provides a natural means to overnourish mouse pups," Waterland said. "Normal size litters have about 10 mice, and served as our control group. The overnourished group came from moms whose litters were reduced to only four pups each. These pups get an 'all you can eat buffet' and become overweight by the time of weaning."

Besides weight, the researchers also applied genome-scale DNA methylation profiling to islets of both overnourished and control pups at 21 days, when they were still weaning, and 180 days, at middle-age “adulthood,” after birth.

They saw that islets from control mice usually gained DNA methylation as they aged, whereas islets of overnourished mice revealed increases in DNA methylation during weaning. Furthermore, there was an overlap between the DNA methylation profile of middle-aged controls and that of the 21-day-old overnourished mice.

"By the age of weaning, islets of overnourished mice show an epigenetic profile resembling that of much older mice," Waterland said. "Our interpretation is that postnatal overnutrition causes accelerated epigenetic aging in the islets. Since the ability to regulate blood sugar declines with age, this premature epigenetic aging may help explain how overnutrition during infancy increases the risk of diabetes later in life."

"In these days of escalating pediatric overnutrition and obesity, we urgently need to understand the adverse consequences of overnutrition in human infancy. I believe that optimizing nutrition during these critical periods of development will prove to be an effective approach to prevent adult disease," Waterland concluded.

These findings are published in <a href="https://academic.oup.com/eep">Environmental Epigenetics</a>.

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Image Credit: Shutterstock/Africa Studio

Overnutrition during infancy could lead to long-lasting health problems

A new study from researchers at Baylor College of Medicine...

Researchers at the <a href="https://www.umassmed.edu/">University of Massachusetts Medical School</a> have used nanoparticles to give mice the ability to see near-infrared light. The experts are now working to modify these nanoparticles to potentially give humans built-in <a href="http://www.earth.com/news/frogs-toads-see-color/">night vision</a>.

"When we look at the universe, we see only visible light," said Dr. Gang Han, who is the principal investigator of the project. "But if we had near-infrared vision, we could see the universe in a whole new way. We might be able to do infrared astronomy with the naked eye, or have night vision without bulky equipment."

Humans and other mammals can detect light between the wavelengths of 400 and 700 nanometers (nm), but near-infrared (NIR) light has longer wavelengths between 750 nm to 1.4 micrometers. 

Dr. Han and his team theorized that mice could be given NIR vision by injecting a special type of nanomaterial called upconversion nanoparticles (UCNPs) into their eyes. UCNPs contain the rare-earth elements erbium and ytterbium, which can convert low-energy photons from NIR light into higher-energy green light that is detectable to the mammalian eye.

In a study published earlier this year, the researchers demonstrated that their theory was correct. Experiments showed that UCNPs allowed the mice to see and mentally process NIR light for at least ten weeks without any known side effects. However, Dr. Han said that the safety of these nanomaterials must be improved before being tested in humans. 

"The UCNPs in our published paper are inorganic, and there are some drawbacks there," said Dr. Han. "The biocompatibility is not completely clear, and we need to improve the brightness of the nanoparticles for human use." 

The team is currently experimenting with UCNPs made up of two organic dyes instead of rare-earth elements. "We've shown that we can make organic UCNPs with much improved brightness compared with the inorganic ones," said Dr. Han. 

One of the next steps for the project could be applying this technology to dogs. "If we had a super dog that could see NIR light, we could project a pattern onto a lawbreaker's body from a distance, and the dog could catch them without disturbing other people."

The research will be presented by Dr. Han at the <a href="https://www.acs.org/">American Chemical Society</a> Fall 2019 National Meeting.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Gang Han

Scientists are a step closer to giving humans built-in night vision

Researchers at the University of Massachusetts Medical School have used...

Skin creams usually contain a few standard ingredients, but manufacturers know little about how these substances interact to influence the product's performance. A team of researchers has investigated the structure of a skin cream on a molecular scale, and they were surprised by what they found.

"The long-term stability and clinical properties of a cream are determined by its fundamental structure," said Delaram Ahmadi, a graduate student at <a href="https://www.kcl.ac.uk/">King's College London</a> who conducted the research. "If we can understand the chemical microstructure of the cream and relate that to the structure of the skin, then perhaps we can better repair the compromised skin barrier."

"We wanted to improve the science around cream formulation so that companies could more rationally formulate them to get exactly what they want," added Dr. David Barlow. "The most significant thing we found is that the textbook picture of the structure of a cream is very naïve."

Dr. Barlow explained that formulators have mostly inferred the structure of these emulsions based on indirect measurements. For their investigation, however, the researchers took a direct approach by analyzing creams using X-ray and neutron scattering techniques to determine how the ingredients were distributed. 

The team expected for a cream to be composed of stacks of lamellae, or membranes, that are made up of surfactants and co-surfactants. These substances reduce the surface tension of the liquid they are dissolved in.

The researchers started with an aqueous cream formulation from the British Pharmacopoeia that contains a sodium dodecyl sulfate (SDS) surfactant and two co-surfactants. The X-rays revealed that the co-surfactants were present in the lamellar layers as predicted, but the surfactant was surprisingly absent.  

"The surfactant peak profile suggested that the molecule formed micelles in the cream," explained Ahmadi. In addition, the preservative was not found in the aqueous layer, where scientists have always thought it would be. Instead, the preservative was found in the lamellae. 

Preservatives have an antimicrobial effect, which gives them a longer shelf life. Formulators assumed that the preservative had to be dissolved in the water layer in order to be an effective <a href="http://www.earth.com/news/antimicrobial-bacteria-spread-urban-wildlife/">antimicrobial</a>. Therefore, according to Ahmadi, the new finding indicates that creams are self-preserving.

"I don't think anybody else has considered that there would be these micelles in the system at all," said Dr. Barlow. "This is new, and we need to think about where they are in the structure and what they are doing."

The research will be presented at the <a href="https://www.acs.org/">American Chemical Society</a> Fall 2019 National Meeting

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Shutterstock/Maryna Pleshkun

Scientists find that skin creams have a surprising molecular structure

Skin creams usually contain a few standard ingredients, but manufacturers...

In a new study published by the <a href="https://www.srcd.org/">Society for Research in Child Development</a>, researchers have investigated the outcome of a program that was developed to improve the quality of <a href="http://www.earth.com/news/screen-time-behavioral-problems/">preschool</a> for low-income children. The focus of the research was to explore how this preschool program may have impacted the academic performance of the students when they reached high school. 

The Chicago School Readiness Project (CSRP) was an experimental teacher development and coaching intervention that was implemented in 35 Head Start classrooms in 2004 and 2005. Head Start centers are federally funded to accommodate preschool students from low-income families. Sites were selected for the study based on their location in high-crime, high-poverty neighborhoods in Chicago, and were randomly assigned to the intervention group or to a control group.

The researchers determined that the CSRP boosted the children's grades in high school years later, which can be partially explained by academic gains made in preschool. The team also found some evidence that the program improved the students' executive function skills, including impulse control and attention, which can be largely attributed to early improvements in math.

Study lead author Dana Charles McCoy is an assistant professor of Human Development and Psychology at the Harvard Graduate School of Education.

"Our results point to the sustained impacts of interventions that provide quality enhancements to existing preschool programming," said Professor McCoy. "In disadvantaged contexts, efforts to improve the well-being of preschool teachers and classroom management appeared to result in long-term benefits for children's academic outcomes, even in the absence of additional supports for instruction."

The high school grades of the CSRP participants were found to be increased by approximately one-quarter of a letter grade. According to the experts, this is primarily due to preschool gains in vocabulary and math skills. The study suggests that short-term improvements in these particular skills laid the groundwork for more advanced academic competencies over time.

"Given recent increases in state and federally funded preschool participation, it's important that we understand both the short- and the long-term impacts of early interventions, as well as the skills that may account for these effects," said study co-author Professor Stephanie Jones.

The study is published in the journal <a href="https://onlinelibrary.wiley.com/journal/14678624">Child Development</a>. 

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Shutterstock

Academic skills gained in preschool have long-term benefits for children

In a new study published by the Society for Research...

Clothing lined with graphene, an ultra-thin nanomaterial comprised of carbon atoms arranged in a lattice configuration, could help prevent mosquito bites. 

Graphene is lightweight, flexible, stronger than steel, and can be used in a single layer or stacked together. There are a wide variety of potential uses for the material including in batteries, solar cells, and even DNA sequencing. 

Researchers from <a href="https://www.brown.edu/">Brown University</a> have now discovered a new use for graphene as a mosquito deterrent. 

The team discovered that graphene layers are impenetrable for mosquitoes in search of a blood meal, and the material blocks the chemical signals a <a href="https://www.earth.com/news/mosquitoes-sense-smell-disease/">mosquito uses to find a host</a>. 

Clothing lined with layers of graphene could keep people safe from disease-carrying mosquitoes. 

The researchers detailed their findings in a new study published in the journal Proceedings of the National Academy of Sciences.

“Mosquitoes are important vectors for disease all over the world, and there’s a lot of interest in non-chemical mosquito bite protection,” said Robert Hurt, a senior author of the study. “We had been working on fabrics that incorporate graphene as a barrier against toxic chemicals, and we started thinking about what else the approach might be good for. We thought maybe graphene could provide mosquito bite protection as well.”

For the study, participants were asked to put their arm in an enclosure filled with lab-bred, disease-free mosquitoes. 

Some of the participants either had a patch of cheesecloth or a graphene oxide lined cheesecloth patch on their skin. The other participants just exposed bare skin to the mosquitoes. 

Only a small patch of skin was exposed, and the researchers recorded how many participants were bitten. 

Graphene repelled mosquitoes, and participants that had the graphene oxide patch didn’t get bit once. Mosquitoes also responded differently when presented with graphene. 

“With the graphene, the mosquitoes weren’t even landing on the skin patch -- they just didn’t seem to care,” said Cintia Castilho, the lead author of the study. “We had assumed that graphene would be a physical barrier to biting, through puncture resistance, but when we saw these experiments, we started to think that it was also a chemical barrier that prevents mosquitoes from sensing that someone is there.” 

The researchers confirmed that graphene acts as a chemical barrier, and some forms of graphene oxide can only effectively prevent mosquitoes from puncturing the material when dry. 

Reduced oxygen content (called rGO) graphene oxide works wet or dry but lacks the breathability of graphene oxide. 

“GO is breathable, meaning you can sweat through it, while rGO isn’t,” said Hurt said. “So our preferred embodiment of this technology would be to find a way to stabilize GO mechanically, so that is remains strong when wet. This next step would give us the full benefits of breathability and bite protection.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com</a> Staff Writer

Image Credit: Hurt Lab / Brown University

Clothing lined with graphene could help deter mosquitoes

Clothing lined with graphene, an ultra-thin nanomaterial comprised of carbon...

Among most human populations, the cannibalism taboo is so strong that ethics don’t matter. Even in life or death situations – such as when the Donner Party was trapped by a blizzard in the Sierra Nevada mountains – survivors often wait until near death before eating, and struggle with the guilt afterward. 

Not so in the animal kingdom, where for many species cannibalism is the norm. Many female insects – including praying mantises and black widow spiders – consume the male after mating. Hamsters and mice may <a href="https://www.earth.com/news/animals-eat-young/">eat their young</a> if they have too large of a litter or are under too much stress. 

Even some herbivores have been recorded munching on their own, such as <a href="https://www.earth.com/news/plants-turn-caterpillars-cannibals/">caterpillars that can’t find enough food</a>, or snack on the wrong leaves.

Among humans, though, the cannibalism taboo leads to an almost visceral reaction. 

“In one of our own experiments, participants were asked to consider the hypothetical case of a man who gave permission to his friend to eat parts of him once he died of natural causes,” Dr. Jared Piazza and Dr. Neil McLatchie wrote for <a href="http://theconversation.com/cannibalism-is-common-in-the-animal-kingdom-heres-why-for-humans-its-the-ultimate-taboo-121678">The Conversation</a>. “Participants read that this occurred in a culture that permitted the act, that the act was meant to honor the deceased, and that the flesh was cooked so that there was no chance of disease. Despite this careful description, about half of the participants still insisted that the act was invariably wrong.”

The pair of psychologists from <a href="https://www.lancaster.ac.uk/">Lancaster University</a> have run a series of experiments in which they question participants about their own beliefs regarding cannibalism and present hypothetical situations intended to test the strength of the cannibalism taboo. 

They pointed out that Roberto Canessa, a survivor of a plane crash in the Andes Mountains that left a soccer team stranded and forced to rely on eating the deceased, described cannibalizing his teammates as “stealing their souls.” This was despite his memory of urging his fellow survivors to eat his body if he should die, they said.

“Our capacity to represent the personalities of the living and the departed is unparalleled. This deep connection between personhood and flesh can mean that careful reasoning in certain situations over the merits of cannibalism is overridden by our feelings of repulsion and disgust,” the pair wrote.

This may also explain why most people are fine with eating some animals, but may recoil at eating those deemed pets. 

“Research shows that the more we think of animals as having human properties – that is, as being ‘like us’ – the more we tend to think they’re gross to eat,” they wrote.

—

By Kyla Cathey, <a href="https://www.earth.com/">Earth.com</a> staff writer

Cannibalism taboo separates humans from other animals

Among most human populations, the cannibalism taboo is so strong...

A large number of teens are using marijuana in its most potent form. Researchers at <a href="https://www.asu.edu/">Arizona State University</a> (ASU) are reporting that nearly 25 percent of teenagers in Arizona have tried cannabis concentrate, a highly potent form of <a href="http://www.earth.com/news/marijuana-use-increased/">marijuana</a>.

The study was focused on nearly 50,000 8th, 10th, and 12th graders who participated in the 2018 Arizona Youth Survey. Overall, 33 percent of the teens had tried marijuana in some form, while 24 percent had tried marijuana concentrate.

Marijuana concentrates have about three times more THC, the main mind-altering compound, compared to what is found in the plant naturally. Professor Madeline Meier, the study's lead researcher, said that this is concerning because higher doses of THC have been linked to increased risk of marijuana addiction, cognitive impairment, and psychosis.

Compared to adolescents who had tried only traditional marijuana, those who tried concentrates were found to have more risk factors for addiction, such as lower perceived risk of harm, peer substance use, and parental substance use.

"This is important because it shows that teens who have a diverse array of risk factors for developing marijuana addiction may be further amplifying their risk for addiction by using high-THC marijuana concentrates," explained study co-author Professor Dustin Pardini.

The study also revealed that teens who had used concentrates had much higher rates of e-cigarette use. According to Professor Meier, one explanation for this could be that teens are using e-cigarettes to vape marijuana concentrate. 

Previous studies have shown that some teenagers use e-cigarettes to conceal their marijuana use. "Vaping marijuana can be passed off as nicotine vaping," said Professor Meier.

Marijuana concentrates do not look like traditional marijuana, and some products resemble wax or oil.

"What concerns me most is that parents might have no idea that their child is using marijuana, especially if their child is using marijuana concentrate," said Professor Meier. "Marijuana is not harmless, particularly for adolescents."

Earlier work by Professor Meier identified a link between frequent marijuana use throughout adolescence and reduced intelligence scores. In addition, prior research by Professor Pardini found that teenagers who use marijuana regularly are more likely to develop persistent subclinical psychotic symptoms.

The study is published in the journal <a href="https://pediatrics.aappublications.org/">Pediatrics</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

A large number of teens are using marijuana in its most potent form

A large number of teens are using marijuana in its...

We waste more food by overeating than directly throwing it away. Researchers from the <a href="https://www.unite.it/UniTE/English">University of Teramo</a> found a way to measure the ecological impact of global food waste caused by overeating. Using global BMI and height data, they first estimated how much net excess bodyweight the overall population of a country has, and then distributed its energy content among food groups based on availability.

The results, published in <a href="https://www.frontiersin.org/articles/10.3389/fnut.2019.00126/full">Frontiers in Nutrition,</a> showed that the amount of direct <a href="http://www.earth.com/news/freshness-sensors-reduce-food-waste/">food waste</a> — that being, food that is discarded and/or lost on the way to the consumer  — is nothing compared to what is wasted on overeating.

"Excess bodyweight corresponds to roughly 140 billion tonnes of food waste globally," said group leader Prof. Mauro Serafini, of the University of Teramo. For comparison, annual direct food waste is estimated at 1.3 billion tonnes.

The impact of what Serafini calls “metabolic food waste” grows when its ecological costs are calculated using per-kilo values from thousands of food lifecycle assessments. For example, fruits, vegetables, roots, and tuebers, have the highest direct wastage rates, however, excess energy consumption is driven by denser caloric foods that usually take more land, water, and greenhouse gases to produce.

In fact, researchers estimate that to grow the world's metabolic food waste would generate about 240 billion tonnes of CO2. This number is about equal to the amount of CO2 produced by burning fossil fuels worldwide over the last seven years. But less certain are the figures that show the total amount of land and water used to produce this amount of metabolic food waste, due to the unknowns when it comes to how long land is required to grow different foods, and/or the redistribution of water. Therefore the researchers cannot make any estimates or conclusions about land usage in terms of metabolic food waste.

Furthermore, Serafini admits that his team’s calculations are based on national availability, not average intake. And the researchers assumed that BMI counts over 21.7 was all excessive fat, even though the understanding of excess bodyweight and its relationship to physical activity is changing.

Even though the estimates are wonky, they are still fairly accurate in a general sense. Therefore, overeating is harming our planet and also harming our health.

--

By <a href="mailto:oliviagharvey24@gmail.com">Olivia Harvey</a>, <a href="http://earth.com">Earth.com</a> Staff Writer

Image Credit: Shutterstock/Lightspring

We waste more food by overeating than directly throwing it away

We waste more food by overeating than directly throwing it...

To humans a whimpering puppy sounds just as sad as a crying baby. The whimpers, whines, meows, and cries of our furry, four-legged friends are just as sad to human ears as the cries from a baby, according to a new study. 

Researchers from <a href="https://international.au.dk/">Aarhus University</a> in collaboration with the <a href="http://www.ox.ac.uk/">University of Oxford</a>, the <a href="http://www.ucla.edu/">University of California, Los Angeles</a>, and <a href="https://www.kcl.ac.uk/">King’s College of London</a> found that pet owners’ devotion and <a href="https://www.earth.com/news/dogs-comfort-owners-upset/">emotional attachment</a> has increased sensitivity to specific vocalizations that signal pain or sadness. 

A whimpering dog has the same effect on pet owners as the sound of a crying baby, the results showed. 

The study was published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.181555">Royal Society Open Science</a> and was part of a larger effort to compile a database of sounds that emotionally resonate with people. 

For the study, 264 dog or cat owners and 297 people who did not own pets were asked to rate the valence of animal distress sounds, or how positive or negative the sounds were. Pet owners rated the dog and cat whines as more negative than those who didn’t own pets. To humans a whimpering puppy sounds just as sad as a crying baby

Cat meows were saddest to cat owners, but both cat and dog owners thought dog whines were more distressing than a cat meowing. 

The reason dog owners may be more attuned and sensitive to a dog whimpering is that in general, dog owners spend more time attending to their pet’s needs than cat owners. Cats are relatively independent, whereas dogs need walks, exercise, and training. 

“The result suggests that dogs, more effectively than cats, communicate distress to humans and that pet ownership is linked to greater emotional sensitivity to these sounds,” said Christine Parson, the first author of the study. 

Because dogs are so dependent on their owners for their needs, care, and attention, they may have evolved the ability to communicate distress more effectively than other pets. 

“This difference in animal dependence may explain why dog whines are rated as more negative than cat meows by all adults, including cat-owners,” said Katherine Young, a senior author of the study. “Dogs may simply have more effective distress signals than cats.”

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Image Credit: Shutterstock/gostua

To humans a whimpering puppy sounds just as sad as a crying baby

To humans a whimpering puppy sounds just as sad as...

Since <a href="https://www.earth.com/news/decriminalizing-medicinal-marijuana/">recreational marijuana</a> was first legalized in Washington and Colorado in 2012, edibles have become a huge part of the cannabis industry. 

Edibles are foods infused with cannabis, and these days you can find everything from gummy bears to cookies to chocolate bars that contain marijuana at dispensaries. 

These cannabinoid-infused treats have flooded the market, but a new study has found that components in chocolate are leading to inaccurate potency test results. 

Edible manufacturers must adhere to strict labeling and potency standards. 

That’s where testing labs come in. David Dawson, a researcher at <a href="http://www.cwanalytical.com/">CW Analytical Laboratories</a>, a cannabis testing lab in California, and his team noticed variations while testing chocolate edibles. 

“My research focuses on cannabis potency testing because of the high stakes associated with it,” said Dawson. “If an edible cannabis product tests 10% below the amount on the label, California law states that is must be relabeled, with considerable time and expense. But it’s even worse if a product tests 10% or more above the labeled amount -- then the entire batch must be destroyed.”

Chocolate edibles are extremely common, and the researchers tested the potency of differently prepared samples. 

The researchers experimented with the amounts of chocolate, the type of chocolate, and the concentrations of Δ9-tetrahydrocannabinol, the major psychoactive component of cannabis. 

“When we had less cannabis-infused chocolate in the sample vial, say 1 gram, we got higher THC potencies and more precise values than when we had 2 grams of the same infused chocolate in the vial,” said Dawson. “This goes against what I would consider basic statistical representation of samples, where one would assume that the more sample you have, the more representative it is of the whole.” 

Chocolate contains a component that is leading to inaccurate results, and the researchers say that this component is suppressing the signal for Δ9-tetrahydrocannabinol. 

“Simply changing how much sample is in the vial could determine whether a sample passes or fails, which could have a huge impact on the producer of the chocolate bars, as well as the customer who might be under- or overdosing because of this weird quirk of matrix effects,” said Dawson. 

The researchers have not pinned down exactly what is hindering the potency tests, but it likely has something to do with the fat content in chocolate as Δ9-tetrahydrocannabinol is fat-soluble. 

The findings will be presented at the <a href="https://www.acs.org/">American Chemical Society </a>(ACS) Fall 2019 National Meeting &amp; Exposition taking place this week through Thursday. 

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette</a>, <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Image Credit: Kevin Kerr

Testing for cannabis potency is problematic in chocolate edibles

Since recreational marijuana was first legalized in Washington and Colorado...

As early humans evolved from their ancient primate ancestors, a helpful genetic mutation arose that created immunity to the simian immunodeficiency virus (SIV), a virus that still plagues primate groups today. 

While this mutation stopped the virus from crossing over to infect humans, eventually the virus found a workaround and SIV evolved to give rise to the <a href="https://www.earth.com/news/drug-treatment-eliminates-hiv-transmission/">human immunodeficiency virus </a>(HIV) which began the AIDS pandemic. 

In a new study, researchers from the <a href="https://www.berkeley.edu/">University of California, Berkley</a> have unlocked the inner workings of how this mutation blocked the SIV virus and how the virus eventually came to infect humans. 

An estimated 38 million people worldwide were living with HIV as of 2018, according to the <a href="https://www.who.int/gho/hiv/en/">World Health Organization</a>, and since the start of the epidemic, 32 million people have died of HIV. 

Before the rise of HIV, early humans developed a mutation in the cells that stopped SIV from hacking the cell’s machinery and making thousands of copies of itself. 

The researchers found that the key was that the mutation disrupted SIV proteins from binding to human proteins. 

“The binding site involved is structurally very complex, so essentially it is not possible to adapt to it once the tight binding is lost. The virus had to invent a completely different way to do the same thing, which took a long time in evolution,” said James Hurley, a co-author of the study. “This conferred an advantage on our prehistoric ancestors: From chimps on down, every primate was susceptible to SIV, but humans were immune.” 

Cryo-electron microscopy was used to analyze the structure of SIV proteins. 

Both SIV and HIV are lentiviruses that take over a host cell, forcing the cell to make copies of the virus, and sending these copies (virions) to infect other cells. 

[caption id="attachment_1876942" align="aligncenter" width="650"]<a href="https://www.earth.com/wp-content/uploads/2019/08/graphic.jpg"><img class="wp-image-1876942" src="https://www.earth.com/wp-content/uploads/2019/08/graphic.jpg" alt="" width="650" height="464" /></a> Image Credit: UC Berkeley image by Cosmo Buffalo[/caption]

The virus wraps its DNA around a piece of the host cell’s membrane to make copies. The cell sheds this piece, and the virus is safely cocooned in a bubble until it finds another cell to infect. 

Typically the immune system would recognize a virus and infection and destroy the entire cell, but SIV found a way to fight these natural defenses. 

SIV virions staple themselves to the cell membrane with something called tetherin. A protein called Nef ramps up the cell’s recycling system forcing the cell to go into overdrive and shed tetherin, whether it’s connected to a virus or not. This allows copies to be safely ejected from the cell. 

Humans developed a mutation which loosened the binding between Nef and the cell proteins and kept the tetherin firmly in place, preventing copies from infecting other cells. 

Eventually, SIV found a workaround, a second protein to wedge in between the proteins and make copies once again. 

“There were probably many crossovers into humans that failed, but eventually, some hunter in Africa, perhaps in the course of butchering a chimp, was exposed to the blood, and the virus then acquired an additional mutation, a small step that turned SIV into HIV,” said Hurley.

The study provides a detailed overview of how early humans evolved a mutation against SIV and the thousands of years it took for SIV to adopt a new strategy and infect human hosts. 

“The main importance for this paper is that it tells us what was one of the last major barriers before the crossover to humans happened,” said Hurley. “The current paper is an archeological look at how this

The researchers published their findings in the journal Cell Host and Microbe.

--

By <a href="mailto:kayvandette@gmail.com">Kay Vandette,</a> <a href="https://www.earth.com/">Earth.com </a>Staff Writer 

Main Image Credit: Shutterstock/monofaction

Early humans were once immune to immunodeficiency viruses

As early humans evolved from their ancient primate ancestors, a...

Research proves that the ‘crazy cat lady’ stereotype is false. After psychoanalyzing the emotional health of individuals with and without pets, a team of researchers at <a href="http://www.ucla.edu/">UCLA</a> has determined that it is time to put the "crazy cat lady" stereotype to rest. The study revealed that <a href="http://www.earth.com/news/cat-owners-hunting-wildlife/">cat owners</a> are no more "crazy" than anyone else.

"We found no evidence to support the 'cat lady' stereotype: cat-owners did not differ from others on self-reported symptoms of depression, anxiety or their experiences in close relationships," wrote the study authors.

The study was focused on the mental health of 264 young adults with cats, dogs, or both. For comparison, the team also evaluated 297 young adults who had no pets.     

The researchers analyzed the potential link between pet ownership and mental health-related or social difficulties, and also observed how the participants reacted to distress calls from animals. 

The experts said that their findings do not support the idea that cat owners tend to be mentally unstable or lonely. In 2017, researchers at University College London came to a similar conclusion. They could not find any evidence that cat ownership is linked with the development of psychotic symptoms.

The UCLA study also demonstrated that cat and dog owners were more likely to react with empathy when they heard the distress calls of an animal. Pet owners were found to be more emotional than people without pets when they heard dog whimpers or cat meows.

"We found several subtle differences between how adults with and without pets generally rated animal vocalizations," said the study authors. 

A growing collection of research has found that caring for a cat or dog has a positive impact on mental health, helping to relieve depression, anxiety, and stress. In addition, pets provide companionship, boost physical activity, and ease loneliness.

The study is published in the journal <a href="https://royalsocietypublishing.org/journal/rsos">Royal Society Open Science</a>.

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: Shutterstock/Alena Ozerova

Research proves that the ‘crazy cat lady’ stereotype is false

Research proves that the ‘crazy cat lady’ stereotype is false....

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=2E0mn5mTvhQ
</div><figcaption class="wp-element-caption">'Death Star' moon Mimas conceals a 15-million-year-old ocean that scientists never expected.</figcaption></figure>



<h2 class="wp-block-heading" id="h-hidden-waters-beneath-ancient-craters">Hidden waters beneath ancient craters</h2>



Scientists have made a startling discovery that challenges everything we thought we knew about <a href="https://www.earth.com/news/saturn-moon-mimas-has-remarkably-young-ocean/" target="_blank" rel="noreferrer noopener">Saturn's moon Mimas</a>. Beneath the heavily cratered surface that earned it the nickname "Death Star" lies a global ocean that formed just 5 to 15 million years ago—a remarkably young age by cosmic standards.



<h2 class="wp-block-heading" id="h-cassini-data-reveals-orbital-secrets">Cassini data reveals orbital secrets</h2>



The discovery, led by Dr. Valéry Lainey of the <a href="https://observatoiredeparis.psl.eu/" target="_blank" rel="noreferrer noopener">Observatoire de Paris</a>, emerged from careful analysis of <a href="https://www.nasa.gov" target="_blank" rel="noreferrer noopener">NASA</a>'s Cassini spacecraft data. By studying subtle irregularities in Mimas's orbit around Saturn, researchers detected the gravitational signature of liquid water hidden 20 to 30 kilometers beneath the moon's icy shell.



<h2 class="wp-block-heading" id="h-an-unlikely-ocean-world">An unlikely ocean world</h2>



At only 400 kilometers in diameter, Mimas seemed like the least likely candidate to harbor a subsurface ocean. Unlike other ocean moons such as Europa and Enceladus, which show clear surface signs of internal activity, Mimas displays no obvious hints of the liquid water beneath its ancient, crater-scarred exterior.



"Mimas is a small moon, and its heavily cratered surface gave no hint of the hidden ocean beneath," explained Dr. Nick Cooper from <a href="https://www.qmul.ac.uk/" target="_blank" rel="noreferrer noopener">Queen Mary University of London</a>, a study co-author.



<h2 class="wp-block-heading" id="h-implications-for-astrobiology">Implications for astrobiology</h2>



The ocean's recent formation makes Mimas a prime target for studying how oceans develop and potentially support life. This discovery adds another member to the exclusive club of ocean worlds in our solar system, each offering unique insights into the conditions necessary for habitability.



The research, published in <a href="https://www.nature.com/" target="_blank" rel="noreferrer noopener">Nature</a> journal, demonstrates how advanced orbital analysis can reveal hidden features of celestial bodies, opening new possibilities for understanding ocean formation throughout the cosmos.



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Scientists discover unexpected young ocean on Saturn's cratered moon Mimas

https://www.youtube.com/watch?v=2E0mn5mTvhQ 'Death Star' moon Mimas conceals a 15-million-year-old ocean that...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=3Y4eLFNYrKE
</div></figure>



On the unforgiving landscape of North Greenland, temperatures drop and sunlight barely penetrates through the polar winter. It was here, however, that an international team of scientists found <a href="https://www.earth.com/news/predatory-worms-were-terror-beasts-half-a-billion-years-ago/#google_vignette" target="_blank" rel="noreferrer noopener">evidence of sea monsters</a> that would change our understanding of ocean life in the past.



This video captures the discovery of Timorebestia fossils that had been hidden for more than 500 million years in the Sirius Passet formation. The "terror beasts," as they are called, are a hidden chapter in the evolutionary history of <a href="https://www.earth.com" target="_blank" rel="noreferrer noopener">Earth</a>, showing that sophisticated predator-prey interactions occurred much earlier than previously envisioned.



Dr. Jakob Vinther and his research team at the <a href="https://www.bristol.ac.uk/" target="_blank" rel="noreferrer noopener">University of Bristol</a>, in collaboration with researchers at the <a href="https://eng.kopri.re.kr/" target="_blank" rel="noreferrer noopener">Korean Polar Research Institute</a>, braved extreme weather conditions at 82.5 north latitude to locate these giant creatures. Using sophisticated electron microprobe analysis, they revealed the detailed anatomy of the animals, including their muscle and nerve tissues.



The find upsets the traditional timeline of sea predators. Although we've long appreciated that Cambrian oceans were at one time ruled by <a href="https://www.youtube.com/watch?v=jWI3-UgA3_o&amp;list=PL1QLQMW9MWDwpkFOnvgAmu7wT6rZmYqdJ&amp;index=19" target="_blank" rel="noreferrer noopener">arthropods</a>, these discoveries indicate that relatives of arrow worms were first to dominate the seas. These worms were building sophisticated food webs several million years before other predator groups arose.



Each fossil is a story of ancient hunger, with fossil stomach contents revealing these meter-long beasts dined on heavily armored arthropods regularly, cementing their place as the ocean's first apex predators.



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Worms dominated seas before dinosaurs

https://www.youtube.com/watch?v=3Y4eLFNYrKE On the unforgiving landscape of North Greenland, temperatures drop...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=Ow3JH03PqEQ
</div><figcaption class="wp-element-caption">New York is the site of the world's oldest forest.</figcaption></figure>



<h2 class="wp-block-heading" id="h-385-million-year-old-trees-discovered">385-million-year-old trees discovered</h2>



Scientists have uncovered something extraordinary just two hours north of New York City. The <a href="https://www.earth.com/news/worlds-oldest-forest-discovered-close-to-new-york-city/" target="_blank" rel="noreferrer noopener">world's oldest forest</a>, dating back 385 million years, offers a window into how Earth's first complex forests shaped our planet's atmosphere.



Located near <a href="https://townofcairo.com/" target="_blank" rel="noreferrer noopener">Cairo, New York</a>, in Greene County, these weren't merely primitive plants struggling to survive. These were sophisticated trees with root systems remarkably similar to modern forests. This ancient woodland predates dinosaurs by 140 million years.



<h2 class="wp-block-heading" id="h-the-cairo-forest-discovery">The Cairo forest discovery</h2>



385 million years ago, upstate New York was a tropical paradise near the equator. Thanks to continental drift, this ancient forest has traveled thousands of miles to its current location.



The fossil forest sits in an abandoned quarry, roughly half the size of a football field. This represents just a slice of what was likely a massive forest system stretching from New York into Pennsylvania.



Charles Ver Straeten, curator of sedimentary rocks at the <a href="https://www.nysm.nysed.gov/" target="_blank" rel="noreferrer noopener">New York State Museum</a>, made the discovery in 2009. While scouting the former highway department property, his trained eye spotted wandering patterns in the stone that looked like marine features.



<h2 class="wp-block-heading" id="h-revolutionary-age-and-preservation">Revolutionary age and preservation</h2>



The site contains 385-million-year-old rocks with fossilized woody roots forming horizontal patterns up to 18 feet (5.5 meters) wide. As Christopher Berry, a paleobotanist at Cardiff University, explains: "You are walking through the roots of ancient trees."



This discovery pushes back advanced tree evolution by millions of years. The research, published in <a href="https://www.cell.com/current-biology/home" target="_blank" rel="noreferrer noopener">Current Biology</a> in December 2019, fundamentally changes our understanding of when complex forests first emerged.



Researchers believe a massive flood buried the forest floor, creating perfect fossilization conditions. Over millions of years, sediment hardened into rock, preserving these root patterns like nature's time capsule.



<h2 class="wp-block-heading" id="h-meet-archaeopteris-the-first-modern-tree">Meet Archaeopteris: the first modern tree</h2>



The star of this ancient forest is Archaeopteris – not to be confused with the feathered dinosaur Archaeopteryx. This tree was far older and more revolutionary.



William Stein from <a href="https://www.binghamton.edu/" target="_blank" rel="noreferrer noopener">Binghamton University</a> describes the roots as "strikingly modern, essentially what you'd see outside in my yard right now." These weren't simple root systems you'd expect from ancient plants.



Some fossilized roots are six inches (15 centimeters) in diameter, forming 36-foot-wide (11-meter) patterns. These giants grew up to 65 feet (20 meters) tall with five-foot-diameter (1.5-meter) trunks.



<h2 class="wp-block-heading" id="h-climate-changing-impact">Climate-changing impact</h2>



These trees fundamentally changed Earth's environment. Kevin Boyce, a Stanford University geoscientist, explains how their deep roots triggered "weathering," chemical reactions that pulled carbon dioxide from the atmosphere.



This process dropped atmospheric CO2 levels from 10-15 times higher than today to roughly modern concentrations. These ancient trees helped create atmospheric conditions that made complex life possible.



<h2 class="wp-block-heading" id="h-ancient-forest-ecosystem">Ancient forest ecosystem</h2>



The forest was remarkably diverse. Scientists identified Eospermatopteris, palm tree-like plants with short roots that reached 30 feet (9 meters) tall but lacked woody structure. The forest also housed cladoxylopsids and a mysterious third species still being studied.



All reproduced through spores rather than seeds – millions of years before seeds evolved. This tropical environment had no grass, flowers, or flying insects, just towering trees creating Earth's first complex forest canopy.



<h2 class="wp-block-heading" id="h-scientific-significance">Scientific significance</h2>



Before this finding, the Gilboa forest, located 25 miles (40 kilometers) away, held the "oldest forest" title. Cairo's trees are 2-3 million years older, showing that complex forest ecosystems developed much faster than scientists believed possible.



Patricia Gensel, a <a href="https://www.unc.edu/" target="_blank" rel="noreferrer noopener">University of North Carolina</a> paleobotanist, notes: "The size of those root systems is really changing the picture. Even 20 years ago, researchers assumed trees with such complex root systems didn't evolve so early."



The Cairo site presents three unique root systems, suggesting Devonian period forests were diverse ecosystems with different trees occupying different environmental niches, much like today's forests.



<h2 class="wp-block-heading" id="h-modern-preservation-efforts">Modern preservation efforts</h2>



In 2022, New York State Senator Michelle Hinchey secured a $170,000 grant for the town of Cairo to construct specialized fencing around the fossil forest site. The town plans to conduct a feasibility study exploring the possibility of creating an educational center and working lab on-site.



Joe Hasenkopf, chair of the Cairo Planning Board, hopes to partner with educational institutions to create a research facility serving scientists, students, and the public.



<h2 class="wp-block-heading" id="h-lessons-for-today-s-climate">Lessons for today's climate</h2>



Why does a 385-million-year-old forest matter today? It shows how dramatically forests can change Earth's climate. These ancient woodlands created the atmospheric conditions supporting complex life.



Understanding how prehistoric forests transformed the planet helps us appreciate modern forests' critical role in addressing climate change. Forests remain Earth's most effective carbon capture systems.



These prehistoric trees changed Earth's atmosphere by pulling massive amounts of carbon dioxide from the air. As we face modern climate challenges, this ancient forest reminds us of trees' incredible power to transform our planet's environment.



The next time you walk through a forest, remember you're experiencing an ecosystem whose blueprint was established 385 million years ago in upstate New York. These ancient pioneers didn't just survive – they thrived and changed the world forever.



The full study was published in the journal Current Biology.



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Earth's oldest forest found in the United States

https://www.youtube.com/watch?v=Ow3JH03PqEQ New York is the site of the world's oldest...

<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://www.youtube.com/watch?v=prrq8Ql81zk
</div><figcaption class="wp-element-caption">Acid rain and a crisis solved.</figcaption></figure>



<h2 class="wp-block-heading" id="h-why-don-t-we-ever-hear-about-acid-rain-anymore-the-environmental-crisis-that-was-solved">Why don't we ever hear about "acid rain" anymore? The environmental crisis that was solved</h2>



Remember the 1980s when acid rain dominated headlines? Dire warnings about rain eating buildings, killing fish, and destroying forests filled every news cycle. Then, almost like magic, acid rain vanished from public discourse. What happened? Did we actually solve one of the late 20th century's most pressing environmental challenges?



The answer might surprise you. Unlike many environmental issues that drag on indefinitely, acid rain represents one of modern history's most successful ecological recovery stories. It's a tale of science, politics, and technology working together to tackle what seemed impossible.



<h2 class="wp-block-heading">What was acid rain?</h2>



Acid rain isn't regular rain having a bad day – it's precipitation that became significantly more acidic due to air pollution. When power plants, factories, and vehicles burn fossil fuels, they release sulfur dioxide (SO2) and nitrogen oxides (NOx) into the atmosphere.



<h2 class="wp-block-heading">The science behind it</h2>



Think of acid rain as nature's chemistry experiment gone wrong. These compounds react with water, oxygen, and other chemicals to form sulfuric and nitric acids. When mixed with water vapor in clouds, they create precipitation with dangerously low pH levels.



While clean rain has a pH of about 5.6, acid rain could drop as low as 4.2 to 4.4 – roughly as acidic as tomato juice or coffee. According to US Geological Survey documentation, Scottish chemist Angus Smith first coined "acid rain" in 1872, but it didn't become a household phrase until the 1960s and 1970s when Swedish scientist Svante Odén documented its devastating effects on Scandinavian lakes and European forests.



<h2 class="wp-block-heading">The crisis at its peak</h2>



During the height of public concern, environmental damage was both widespread and visible. This wasn't some abstract future threat – people could see destruction happening in real-time.



<h2 class="wp-block-heading">Environmental devastation</h2>



The most dramatic impacts were impossible to ignore. Research documented by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation shows that in the Adirondack Mountains, more than 200 lakes became so acidic they couldn't support fish life. The Adirondack Council reports that 409 lakes once supported brook trout, but many lost their fish populations due to acid rain.



By 1976, when scientists cataloged all acidified lakes in the Adirondack Park, researchers found that half of the lakes over 2,000 feet above sea level had no fish, according to studies published in environmental journals. The acidification process worked like a slow-motion disaster. As acid rain fell into watersheds, it gradually lowered pH levels. Fish couldn't survive in acidic water, and their food sources died off too.



Trees at high elevations showed stress directly linked to acid rain. It weakened them by leaching nutrients and making them susceptible to disease. Historical records show Germany's Black Forest saw nearly half its trees damaged by the mid-1980s.



<h2 class="wp-block-heading">Economic impact</h2>



Acid rain wasn't just environmental – it was expensive. Acidic precipitation corroded infrastructure, buildings, and monuments. Historic stone structures deteriorated at accelerated rates. Tourism suffered as lakes became fishless and forests declined. EPA economic analyses from the period documented repair costs mounting into billions annually.



<h2 class="wp-block-heading">The solution: government action and technology</h2>



Transformation from crisis to success required unprecedented cooperation between governments, industries, and environmental groups.



<h2 class="wp-block-heading">The Clean Air Act of 1990</h2>



The turning point came with the Clean Air Act Amendments of 1990, signed by President George H.W. Bush. This represented a fundamentally new approach to environmental regulation, as documented in EPA historical records.



<h2 class="wp-block-heading">Cap-and-trade success</h2>



Instead of mandating specific technologies, the 1990 amendments introduced something revolutionary: a cap-and-trade system for sulfur dioxide emissions. EPA program documentation shows this market-based approach set overall limits but allowed companies to trade emission allowances.



The genius was harnessing market forces to find cost-effective pollution reduction. Companies reducing emissions cheaply could sell excess allowances to those facing higher costs. Research published in environmental economics journals and EPA progress reports shows this resulted in dramatic SO2 reduction at a fraction of projected costs.



<h2 class="wp-block-heading">Technology advances</h2>



Policy provided the framework, but technology made reductions possible. Studies in atmospheric science journals document the widespread adoption of flue gas desulfurization systems ("scrubbers") that removed sulfur dioxide before it reached the atmosphere. By the 2000s, new installations could remove over 95% of SO2 emissions, according to EPA technical reports.



The push coincided with cleaner energy development. Natural gas produces fewer sulfur compounds than coal. Wind and solar, emerging in the 1990s, captured growing market share, reducing reliance on high-sulfur coal.



<h2 class="wp-block-heading" id="h-why-we-don-t-hear-about-it-today">Why we don't hear about it today</h2>



Why did acid rain disappear from headlines? Simple: the problem was largely solved.



<h2 class="wp-block-heading">Success doesn't make news</h2>



There's an old journalism saying: "If it bleeds, it leads." Environmental success stories don't generate urgency like crisis reporting. Media attention shifted to other challenges: climate change, plastic pollution, and biodiversity loss. There's only so much environmental anxiety the public can absorb, and newer concerns replaced acid rain.



<h2 class="wp-block-heading">Mission accomplished</h2>



The primary reason is beautifully simple: interventions worked. EPA monitoring data shows sulfur dioxide emissions dropped over 90% since 1990. Academic research published in environmental science journals confirms pH levels in formerly affected areas returned closer to normal. This represents one of history's most dramatic environmental recoveries. Studies by the Adirondack Lakes Survey Corporation show fishless lakes now support healthy populations. Forests recovered, and building damage slowed dramatically.



<h2 class="wp-block-heading" id="h-is-it-really-gone">Is it really gone?</h2>



The crisis is largely resolved, but monitoring data shows the problem isn't completely eliminated – it's managed to acceptable levels. Some areas still experience occasional events during high pollution periods. International environmental research indicates that rapidly industrializing Asian countries face similar problems to what we experienced decades ago, though they're implementing successful strategies.



EPA research shows nitrogen oxide emissions proved more challenging than sulfur dioxide, coming from vehicles and mobile sources. Climate science studies suggest changing weather patterns add complexity to how acid rain forms and falls.



<h2 class="wp-block-heading">What this teaches us</h2>



The acid rain experience proves that seemingly intractable environmental problems can be solved with scientific understanding, political will, and technological innovation. Environmental monitoring data shows recovery speed was remarkable – within a decade, measurable improvements appeared in air quality and ecosystem health.



Success came from bipartisan support across party lines. Policy analysis studies show the market-based approach appealed to those preferring economic incentives while achieving environmental goals. This support created lasting policy surviving political changes.



<h2 class="wp-block-heading">Conclusion</h2>



Acid rain's disappearance from public consciousness represents environmental science's greatest success stories. Through effective regulation, technological innovation, and international cooperation, we transformed an overwhelming crisis into a manageable challenge.



Today's silence isn't because we forgot – it's because we solved it. The 1990 Clean Air Act, combined with technology and energy market changes, reduced acid rain emissions over 90%, according to comprehensive EPA data analysis.



This success offers hope for current challenges. It proves complex problems can be solved when science, policy, and technology work together. As we face climate change and plastic pollution, acid rain reminds us that dramatic positive change is possible.



Next time someone asks whether environmental regulations work, remember acid rain. It's proof that sometimes, we get it right.



<hr class="wp-block-separator has-alpha-channel-opacity"/>



Sources: This article draws from EPA official documentation and progress reports, peer-reviewed research published in environmental and atmospheric science journals, historical data from the Adirondack Lakes Survey Corporation, New York State Department of Environmental Conservation records, US Geological Survey publications, policy analysis studies, and environmental monitoring data collected over three decades.



<h2 class="wp-block-heading">Frequently Asked Questions</h2>



1. Is acid rain completely gone? No, but EPA monitoring shows it's reduced to manageable levels. US sulfur dioxide emissions dropped over 90% since 1990, making acid rain much less severe than the 1980s crisis.



2. How long did solving take? Environmental monitoring data shows significant improvements began within 5-10 years of 1990s emission controls. Full ecosystem recovery took longer – some areas need 20-30 years for complete recovery.



3. What made the solution successful? Clear scientific understanding, visible damage motivating action, bipartisan support, available technology, and innovative market-based policies like cap-and-trade.



4. Do other countries have acid rain problems? Yes, particularly rapidly industrializing Asian countries. However, international environmental research shows many implement similar successful control strategies.



5. Could acid rain return? Potentially, if regulations weaken or we return to high-sulfur coal without controls, though effects would take years to become severe according to environmental projections.



6. Can you recommend any teaching tools on the subject of "acid rain"? The United States Environmental Protection Agency produced a wonderful teacher's guide for ages 14 and under that you can find on the EPA website here: <a href="https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf" target="_blank" rel="noreferrer noopener">https://www.epa.gov/sites/default/files/2017-03/documents/teachersguide.pdf</a>



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The environmental problem we actually solved

https://www.youtube.com/watch?v=prrq8Ql81zk Acid rain and a crisis solved. Why don't we...

Fresh,Radish,Harvest,On,Soil,In,Garden.

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Mid-July is an opportune time to kick-start a thriving fall garden, and this guide lays out the best vegetables and herbs to plant now for a fruitful autumn harvest. 



Fast-growing leafy greens such as spinach, lettuce, kale, and arugula perform especially well in the waning summer heat, with harvests beginning as soon as 30 days. 



These cool-season crops relish the transition into fall, offering repeated yields with cut-and-come-again methods.



Root vegetables like radishes, carrots, and beets also excel during this period. Radishes deliver satisfaction in under a month, while carrots and beets mature in about two months. Employing succession planting ensures a continuous stream of produce deep into the cooler months. 



For a boost of fresh flavor, herbs like cilantro, basil, dill, and chervil are excellent picks. These heat-loving varieties flourish in July’s warmth and are harvest-ready in about 30 days, especially when sown continuously.



Gardeners in zones 6 through 9 can benefit from planting bush beans and snap peas, which don’t require trellising and are ideal for compact plots. 



Maturing in 50–60 days, they’re a smart choice for quick, protein-rich harvests. For those in hotter regions, heat-tolerant crops such as okra and southern peas provide reliable yields and thrive in scorching conditions.



This guide emphasizes more than crop selection—it highlights the importance of timing, soil preparation, and ongoing sowing techniques. 



With thoughtful planning and attention to regional climate needs, even late-summer gardeners can enjoy fresh salads, hearty stews, and the satisfaction of a robust, homegrown harvest well into fall.



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What to plant in your garden in mid-July

https://youtu.be/Fi2OeEwuzRM?si=vTyd2m9FMmtyWkex Mid-July is an opportune time to kick-start a thriving...

Green,Ecoduct,Over,An,Empty,Highway,During,Sunset.

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A new long-term study in Monkton, Vermont, reveals that wildlife tunnels significantly reduce amphibian road mortality during seasonal migrations. 



Frogs and salamanders often cross roads to reach breeding ponds each spring, but many are killed by vehicles. 



Researchers from the <a href="https://www.uvm.edu/" target="_blank" rel="noreferrer noopener">University of Vermont</a>, in collaboration with local citizens and the Vermont Agency of Natural Resources, installed two underpass tunnels in 2015. 



Over a 12-year monitoring period, they observed an 80.2% reduction in amphibian deaths, and up to 94% for non-climbing species like salamanders. 



The study used a before-after-control-impact design and documented more than 5,200 amphibians, highlighting the tunnels’ effectiveness even in nearby buffer zones.



Funded at $342,397 - far cheaper than wildlife crossings for large mammals - the project showcased the power of community-led conservation.



Local groups initiated the effort after observing mass amphibian deaths. Wildlife cameras later captured over 2,200 amphibians using a tunnel in just one spring, along with other species like raccoons and bobcats, indicating wider ecosystem benefits.



This marks the first peer-reviewed, long-term data set in the northeastern U.S. confirming amphibian-specific underpasses work. 



The study urges transportation departments to incorporate these designs into road planning and highlights how community action, thoughtful infrastructure, and persistence can make a real difference for biodiversity.



The full study was published in the <a href="https://linkinghub.elsevier.com/retrieve/pii/S1617138125000780" target="_blank" rel="noreferrer noopener">Journal for Nature Conservation</a>.



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Wildlife tunnels save millions of amphibians

https://youtu.be/XYgiPzmNBTU?si=eFYY7gPHU1JznLvU A new long-term study in Monkton, Vermont, reveals that...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



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https://youtu.be/Ug657J67iEo?si=w96YjGMsg939LD_3
</div></figure>



Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nushagak Bay in southwest Alaska

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lake Trasimeno in Central Italy

[sendtonews key="3upvlAaHgO-2256633-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> explores the ability of salt to transform the way that foods and beverages taste. Salt is known to cover up undesirable flavors, such as bitterness in coffee or beer, but how exactly does sodium chloride change the taste of other compounds?



One previous study showed that, not only does salt suppress bitterness, but also enhances sweetness and sourness. Another study revealed that bitterness reduction by salt seems to be happening at the tongue receptor level as well as in the brain.&nbsp;



While it is known that salt taste is mediated by the presence of sodium channels in the form of taste buds, experts believe that there is also an unknown receptor responsible for how we taste salt that has not yet been identified.&nbsp;



Video Credit: ACS Reactions



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

How does salt makes things taste better?

[sendtonews key="X0f6OHYoI4-2310561-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



'The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September)."



"The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries," says ESA.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Santiago, Chile in South America

[sendtonews key="JRaP49ISmm-2357509-12187" type="single"] Today’s Video of the Day from the...

Spiral,Galaxy,,Illustration,Of,Milky,Way

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Astronomers at <a href="https://www.jhu.edu/">Johns Hopkins University</a> have created an interactive map of the universe, including the actual position and real colors of 200,000 galaxies. The map allows the public to access data that was previously only available to scientists.



The map was developed using data collected by the Sloan Digital Sky Survey. For over two decades, a telescope in New Mexico was aimed at slightly different locations to capture the night sky.&nbsp;



"Growing up I was very inspired by astronomy pictures, stars, nebulae and galaxies, and now it's our time to create a new type of picture to inspire people," said map creator Brice Ménard, a professor at Johns Hopkins. "Astrophysicists around the world have been analyzing this data for years, leading to thousands of scientific papers and discoveries. But nobody took the time to create a map that is beautiful, scientifically accurate, and accessible to people who are not scientists. Our goal here is to show everybody what the universe really looks like."



"In this map, we are just a speck at the very bottom, just one pixel. And when I say we, I mean our galaxy, the Milky Way which has billions of stars and planets. We are used to seeing astronomical pictures showing one galaxy here, one galaxy there or perhaps a group of galaxies. But what this map shows is a very, very different scale."



"From this speck at the bottom, we are able to map out galaxies across the entire universe, and that says something about the power of science."



The <a href="https://mapoftheuniverse.net/">interactive map</a> is available online, where it can be downloaded for free.



Video Credit: Johns Hopkins&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Interactive map of the universe includes 200,000 galaxies

[sendtonews key="e4ZG0Jawp3-2374785-12187" type="single"] Astronomers at Johns Hopkins University have created...

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Lesotho: Africa's "Kingdom in the Sky" Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features northwest Lesotho in South Africa.



According to ESA, Lesotho is the only nation in the world that lies completely above 1,000 m in elevation. The country is famous for its tall mountains and narrow valleys, and is known as Africa's "Kingdom in the Sky."



Out of a population of around two million people, about 80 percent live in rural areas. More than 75 percent of these people are engaged in <a href="https://www.earth.com/news/climate-change-will-have-a-global-impact-on-agriculture/">agriculture</a>, including rainfed cereal production and animal grazing.&nbsp;



ESA reports that the country’s agricultural system faces a growing number of issues, with climate-related vulnerabilities such as drought, floods and extreme temperatures occurring more frequently. 



Diamonds are amongst the minerals found in the mountains. Indeed, Lesotho can truly be called the Kingdom in the Sky. Beautiful, culturally rich, safe, affordable, and easily accessible from Durban and Johannesburg, mountainous Lesotho is a vastly underrated travel destination. the Kingdom of Lesotho (Sotho: 'Muso oa Lesotho) is an enclaved country in southern Africa. It is just over 30,000 km2 (11,583 sq mi) in size and has a population of around 2 million.



Video Credit: ESA&nbsp;&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer 



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Lesotho: Africa's "Kingdom in the Sky"

[sendtonews key="uV9Lh2fQbV-1760058-12187" type="single"] Lesotho: Africa's "Kingdom in the Sky" Today’s...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The city of Dublin on Ireland's east coast

[sendtonews key="qjvhBOBnY8-2426650-12187" type="single"] Today's Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The province of Zaragoza in northeast Spain

[sendtonews key="oL4FnPTGCV-2384527-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

The rapid retreat of the Columbia Glacier

[sendtonews key="0879czfG3k-1785905-12187" type="single"] Today’s Video of the Day from NASA...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

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[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Two distant planets may be "water worlds"

[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"] Today's Video of the Day from NASA...

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