For many years, scientists have predicted that many of the elements that are crucial ingredients for life, like sulfur and nitrogen, first came to Earth when asteroid-type objects carrying them crashed into our planet’s surface.

But new research published by our team in Science Advances suggests that many of these elements, called volatiles, may have existed in the Earth from the beginning, while it formed into a planet.

Volatiles evaporate more readily than other elements. Common examples include carbon, hydrogen and nitrogen, though our research focused on a group called chalcogens. Sulfur, selenium and tellurium are all chalcogens.

Understanding how these volatile elements made it to Earth helps planetary scientists like us better understand Earth’s geologic history, and it could teach us more about the habitability of terrestrial planets beyond Earth.

Why it matters

The popular “late veneer” theory predicts that Earth first formed from materials that are low in volatiles. After the formation of the Earth’s core, the theory says, the planet got volatiles when volatile-rich bodies from the outer solar system hit the surface.

These objects brought around a half a percent of Earth’s mass. If the late veneer theory is right, then most elements that make up life arrived on Earth sometime after the Earth’s core had formed.

But our new research suggests that Earth had all its life-essential volatile elements from the very beginning, during the planet’s formation. These results challenge the late veneer theory and are consistent with another study tracing the origin of water on Earth.

How we did our work

To study the origin of volatiles in the Earth, we used a computational technique called first-principles calculation. This technique describes the behaviors of isotopes, which are atoms of an element that have varying numbers of neutrons. You can think of an element as a family – every atom has the same number of protons, but different isotope cousins have different numbers of neutrons.

Different isotopes behaved slightly differently during each stage of Earth’s formation. And the isotopes left behind a signature after each formation stage that scientists can use as a kind of fingerprint to track where they were throughout Earth’s formation.

First-principles calculation allowed us to calculate what isotope signatures we’d expect to see for different chalcogens, depending on how the Earth formed. We ran a few models and compared our isotope predictions for each model with the actual measurements of chalcogen isotopes on Earth.

We found that while many volatiles evaporated during Earth’s formation, when it was hot and glowing, many more are still left over today. Our findings suggest that most of the volatiles on Earth now are likely left over from the early stage of Earth’s formation.

What’s next

While chalcogens are interesting to study, future research should look at other critical-for-life volatiles, like nitrogen. And more research into how these volatiles behave under extreme conditions could help us know more about how isotopes were behaving during each of the growth stages of Earth’s formation.

We also hope to use this approach to see whether some exoplanets – planets beyond our solar system – could be habitable to life.

The Research Brief is a short take about interesting academic work.

Shichun Huang, Associate Professor of Earth and Planetary Sciences, University of Tennessee and Wenzhong Wang, Professor of Planetary Science, University of Science and Technology of China

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Every year, Americans buy somewhere between 35 million and 50 million Christmas trees, and many more pull an artificial tree out of storage for the season. In all, about three-quarters of U.S. households typically have some kind of Christmas tree, surveys show.

People often ask which is more sustainable – a real tree or an artificial one? It’s a big debate, and the answer depends on who you ask and which factors you consider.

A more useful question is: How do I find the most sustainable tree of the kind I want to get?

I’m a forestry professor who works on issues of sustainability. There are advantages and disadvantages to both cut trees and artificial trees. Here are some tips to consider for each.

If you’re buying a live Christmas tree

When Christmas trees are alive and growing, they pull carbon dioxide from the air and use it as the building blocks of their wood. That keeps the greenhouse gas out of the atmosphere, where too much carbon dioxide contributes to global warming.

This process stops once the tree is harvested. And at some point, the cut tree begins to decompose and releases that carbon again.

On the positive side, the tree’s root systems will continue to store carbon for some time, and new trees are typically planted to continue the cycle.

So, how do you find the most sustainable live tree?

Think about the tree’s origin

If you live in Mississippi, like I do, buying a noble fir (Abies procera) means your tree probably came from the Pacific Northwest. That’s a long drive, and transportation is a major source of greenhouse gas emissions. However, in a truck with several hundred trees, each individual tree’s transportation emissions are pretty minor.

The most common Christmas tree varies by region: Douglas-fir is also common throughout the Mountain West. Scotch pine and balsam fir are regularly grown in the Great Lakes states. Fraser fir is also popular there but dominant in North Carolina. Leyland cypress and Virginia pine are common in the Southeast.

There are many other wonderful species grown locally. Of course, the lowest-impact cut tree is the one you cut from your own yard.

Also, look for local nurseries that protect their soils from erosion and minimize harm to surface and groundwater from runoff that can include fertilizers or pesticides.

Disposing of your live tree

What you do with your tree after the holidays also matters.

Recycling is far better than leaving the wood to decompose in a landfill. Because of the nature of most landfills, anaerobic conditions will ultimately exist, and decomposition will result in the release of methane gas, which is many times more potent than carbon dioxide at warming the atmosphere.

Look for a community or retailer that offers to chip the tree or shred it to create mulch or for use in animal stalls. This keeps it out of landfills and serves a purpose.

Composting is another option. Trees can be used as an erosion barrier for sand or soil or as fish habitat in lakes. They can even be donated whole to zoos, where the trees provide entertainment for animals while eventually decaying outside of a landfill, or they can be tossed into a bio-burner to provide heating for buildings. Some people even feed trees to goats.

Alternatively, consider cutting the tree into smaller pieces and letting it rot in the open, placing it in an out-of-the-way place in your yard. It will provide a temporary home for many insects, birds and wildlife.

Artificial trees have different pros and cons

Artificial trees also have advantages – they can last for years and require almost no maintenance. However, they are mostly a petroleum-based product, and when you throw one out, it can take hundreds of years to decompose.

If you plan to buy an artificial Christmas tree – maybe you have allergies like I do, or you’re concerned about cost – here are some suggestions to reduce your carbon footprint.

Reuse, reuse, reuse

The No. 1 way to reduce emissions with an artificial tree is to reuse it for years. Reuse avoids the carbon impact of producing, packaging and shipping a new one. The break-even point – when your artificial tree’s emissions match the emissions of buying a live tree each year – varies from as little as four years to as many as 20 years, depending on the factors considered.

Many artificial trees are built to last 30 years or more. My family has had one for 25 years. To lengthen its life span, take care when putting it up and storing it. If the tree gets damaged, see if you can find replacement parts rather than replacing the entire tree.

Pay attention to the source

About 80% of artificial Christmas trees are manufactured in China. Shipping is pretty efficient, but the tree still needs to get to and from the ports. You can also look for one manufactured nearby instead.

Some manufacturers are making trees out of recycled materials, at least in part, which helps reduce the tree’s carbon footprint. Shorter artificial trees, or designs with less foliage, also use less plastic.

The type of plastic used also affects the amount of petroleum used. Some research has suggested that plastic foliage made from polyethylene plastic molds may have a lower impact than traditional foliage made out of polyvinyl chloride, or PVC.

Give the fake tree a second life

If you no longer like your artificial tree – maybe it’s too big for a new home – try reselling the tree or donating it to a charity, thrift store or nursing home so that others can continue to use it.

You can also get creative and repurpose the old tree limbs into decorative wreaths, garlands or toy trees for a hobby train set.

Lighting also matters

With any holiday tree, be judicious about turning off lights when no one is around and at night. Consider using fewer lights. LED lights are more energy efficient than incandescent lights.

In the grand scheme of the holidays, with people traveling and buying and returning gifts through the mail, the carbon footprint of your Christmas tree is a lesser concern. A round-trip flight from Los Angeles to Boston can produce more than 30 times the lifetime emissions of a typical artificial Christmas tree. Still, it’s fairly easy to make more sustainable choices and reduce your carbon footprint when you can.

Curtis VanderSchaaf, Assistant Professor of Forestry, Mississippi State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This winter, tens of thousands of birders will survey winter bird populations for the National Audubon Society’s Christmas Bird Count, part of an international bird census, powered by volunteers, that has taken place every year since 1900.

For many birders, participating in the count is a much-anticipated annual tradition. Tallying birds and compiling results with others connects birders to local, regional and even national birding communities. Comparing this year’s results with previous tallies links birders to past generations. And scientists use the data to assess whether bird populations are thriving or declining.

But a change is coming. On Nov. 1, 2023, the American Ornithological Society announced that it will rename 152 bird species that have names honoring historical figures.

Soon, Christmas bird counters will no longer find Cooper’s hawks hunting songbirds. They won’t scan marshes for Wilson’s snipes. And here in Colorado’s Front Range, where I’ll participate in a local count, we’ll no longer encounter one of my favorite winter visitors, Townsend’s solitaires.

New names will take the place of these eponymous ones. With those new names will come new ways of understanding these birds and their histories.

Names matter

In my time birding over the past decade, learning birds’ names helped me recognize the species I encounter every day, as well as the ones that migrate past me. So I understand that it may not be easy to persuade people to accept new names for so many familiar North American species.

But as a scholar of politics, culture and denial, I also know that language shapes our understanding of history and violence. This includes bird names, as I’ve learned through my ongoing research into one iconic species’ place in American culture: the Eastern whip-poor-will.

Eastern whip-poor-wills are nocturnal birds who nest in forests of the eastern U.S. and Canada. English colonialists named the species for their distinct, repetitive call, which sounds like a malicious command to inflict punishment: “Whip poor Will, whip poor Will, whip poor Will.”

This naming had consequences. Generations of poets and naturalists, like John Muir and Mabel Osgood Wright, associated the species with whippings. Their writings often tell us as much about 19th and early-20th century Americans’ views of morality and punishment than about this remarkable bird.

What’s wrong with eponymous names

The whip-poor-will’s name translates the species’ song, leaving room for interpretation. Eponymous names based on a specific person, like Audubon’s oriole or Townsend’s solitaire, are less descriptive. Even so, these names shape how people relate to birds and the history of ornithology.

Many of these names honor people, usually white men, who engaged in racist acts. For example, John James Audubon owned slaves, and John Kirk Townsend robbed skulls from Native American graves. Changing these names helps separate birds from this harmful, exclusionary history.

But for multiple reasons, the American Ornithological Society is changing all eponymous names, not just those linked to problematic historical figures. First, the organization decided that it did not want to make judgments about which historical figures were honor-worthy. Second, it recognized that all eponymous names imply human ownership over birds. Third, it acknowledged that eponymous names do not describe the birds they name.

Change as a constant

While birders certainly will have learning to do once these changes become official, change is a constant in how people relate to birds.

Consider the technologies birders use. In the early 20th century, binoculars became more affordable and readily available. As Texas A&M historian Thomas Dunlap has shown, this helps explains why birders now “collect” birds by spotting them, rather than by shooting them, as Audubon and others of his time did.

Field guides, too, have come a long way. Early guides often relied on dense written descriptions. Today, birders carry compact, smartly illustrated guides, or we use smartphones to check digital guides, share sightings and identify birds from audio recordings.

Names, too, have long been open to revision. When the American Ornithological Union, the predecessor of today’s American Ornithological Society, created an official list of bird names in 1886, it erased untold numbers of Indigenous names, as well as local folk names.

Since then, some names have come into use and others have fallen out of fashion, especially as ornithologists lump and split species. Consider the ongoing adventure of just one species: Wilson’s snipe, a round marsh bird whose name will be among those changed.

In the American Ornithological Union’s original checklist of North American birds, Wilson’s snipes were a distinct species from the Common snipes of Europe and Asia. Then, in the mid-1940s, the Union decided the two were one, and Wilson’s snipes became Common snipes. In 2000, the Common snipe was split back into two species, and Wilson’s snipes again became Wilson’s snipes.

Either way, many early accounts of the North American species simply call these birds “Snipes.” This is the name Alexander Wilson, for whom the bird is named, himself used in his account of them.

Names reflect new knowledge and values

Science has greatly expanded human understanding of birds in recent decades. We now recognize that birds are intelligent, with rich emotional lives. Radar, lightweight transmitters and satellite telemetry have helped scientists map the transcontinental migrations that many bird species make each year.

Trading eponymous names, which treat birds as passive objects, for richer descriptive names reflects this sea change in our understanding of avian lives.

Our thinking about race and racism has evolved dramatically as well. For instance, we no longer use folk names for birds based on racial and ethnic slurs, as Americans of the 19th and early 20th centuries did. The decision to change eponymous bird names reflects this shift.

It also reflects broader efforts to reckon with the legacies of racism and colonialism in our relationships with the natural world. There is increasing recognition that legacies of racism shape our natural landscapes. Just as public monuments can have “expiration dates,” so can names for species, geographic features and places that no longer reflect contemporary values.

Birders no longer live in Audubon’s world. We rarely consult his heavy, multi-volume folios. We celebrate that we list birds that we have seen in the wild and left unharmed, rather than collecting their bodies as specimens.

Soon, we’ll also stop using some of the names that this world gave to birds.

Jared Del Rosso, Associate Professor of Sociology and Criminology, University of Denver

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Just as the shift to shorter days and colder weather can bring with it mood swings and other emotional challenges, the holiday season can also bring about somewhat predictable changes in mood and behavior.

Around this time of year, many of us experience more stress, anxiety and frustration than usual. These stressors have been linked to higher levels of heart failure and alcohol poisoning and an increase in deaths from stroke.

Learning how to recognize what brings about stress and what parts of the brain are actively involved can help with managing the stress response.

As a neuroscientist, I am often curious about the dynamic connection between behavior and the brain. I’ve learned that, biologically speaking, there are ways to manage your responses to holiday stressors through awareness of why they happen.

Harnessing the hypothalamus

Delays in itineraries, crowded airports and congested highways can easily lead to frustrations for those traveling to spend time with family or friends.

One region of the brain involved in your response to these types of stresses is the hypothalamus, a structure deep in the brain that is involved in trying to keep the body in a stable state, known as homeostasis. The hypothalamus works to regulate the autonomic nervous system, a system that coordinates involuntary responses such as heart rate, blood pressure and respiration. It is the key component of the fight-or-flight response to real or perceived threats.

When you are under stress, such as when you learn that your flight has been delayed or even canceled, your hypothalamus stimulates the release of stress hormones such as cortisol and epinephrine. These hormones in turn trigger physiological responses like increased heart rate, perspiration and feelings of irritation and frustration.

When you experience these stressors, deep breathing exercises can help stimulate the body’s parasympathetic nervous system. This is known as the “rest and digest” system because it is responsible for helping your body relax and recover from stress. By taking slow, deep breaths, you can engage the parasympathetic nervous system, which can in turn calm your nerves and reduce frustrations.

Family dynamics and interactions

Getting together with family during the holidays can bring about complicated emotions when there are conflicting personalities, unresolved issues or awkward family dynamics.

Frustrating or aggravating conversations with relatives often trigger a region of the brain known as the anterior cingulate cortex. The anterior cingulate cortex has a unique position in the brain, establishing connections with both the “emotional” limbic system and the “cognitive” prefrontal cortex.

This brain region is involved in monitoring and regulating cognitive processes, conflict resolution and error detection. It plays a role in processing frustration by signaling when there is a conflict between expectations and outcomes. The anterior cingulate cortex is also involved in what’s known as action-outcome learning, where you evaluate the consequence of an action and adjust your behavior based on feedback.

When you are feeling overwhelmed or frustrated, taking short breaks to step away from the situation can provide a fresh perspective and allow you to return with a clearer mindset. This break will allow you to reinforce this action-outcome learning, helping you learn to associate an action – a short break – with the outcome of the action, which is more relaxed breathing and a clearer mind.

Financial worries

The holiday season can put an unnecessary burden on those who are experiencing economic or financial hardship. The cost of hosting a holiday meal, buying gifts or traveling can contribute additional financial strain during an already stressful time.

The brain region primarily associated with memory and learning is the hippocampus. When you recall past experiences, such as how much you spent last year during the holidays or remember that the credit card bill is coming soon, you activate your hippocampus. The hippocampus is critical in the interplay of memory formation and recall and retrieval of individual episodic memories.

Some ways to reduce stress may be to make gifts for friends and family instead of purchasing them. To help cut down on travel costs, perhaps take a virtual holiday visit now, followed by an in-person visit later when it is less expensive or when financial strains have eased. When reminded of stressful experiences, the hippocampus sends signals to the hypothalamus and other brain regions to help restore balance in your mind. The hippocampus also aids in your adaptation to these stressors by helping you learn how to adjust your expectations. In the end, you have to remind yourself that it truly is the thought that counts most.

Loneliness and isolation

Feelings of isolation and loneliness can arise for those of us who may not have family or friends to celebrate with, or perhaps are unable to travel to see those we love.

This is where the “default network” of the brain plays a role. This network, made up of brain regions including the amygdala, is involved in thoughts of future planning, reminiscing and imagining. The amygdala is a part of the limbic system and is associated with processing of negative emotions to stimuli, such as the irritation from not being able to travel, and how you react.

Studies have shown that you can help improve your mood and reduce feelings of frustration and irritation by having a regular exercise routine. Physical activity can be an effective outlet for releasing built-up tension and stress. Aerobic exercise can also modulate connections between and within the amygdala and help reduce feelings of depression. As an added bonus, if you work out in a gym or park, you have an opportunity to be around others, which can help you feel more connected with communities of people with similar interests.

Political discussions

Family gatherings can lead to discussions about current events or politics, which can result in heated debates and disagreements among family members. These conversations can be very frustrating and even upsetting, especially in today’s polarized world.

The prefrontal cortex is an area of the brain involved in impulse control, decision-making and emotional regulation. It plays a crucial role in assessing certain situations, such as supercharged conversations, and it helps you evaluate and consider your potential actions and temper your emotional responses. Understanding what triggers your frustration in these situations is crucial to developing proactive strategies to manage or avoid them.

For instance, this might take the form of empathizing with the opposing side or perhaps stepping away from the table when voices start to rise or you feel your emotions building. The prefrontal cortex plays a dual role in regulating the relationship of your initial emotional reaction and the shift to your empathetic emotion. Your ability to build empathetic perspectives and increase cognitive control helps to further develop your prefrontal cortex, potentially making it easier to de-escalate the next time around.

One step at a time

Reducing frustration is a gradual process, and different strategies work for different people.

It is important to identify the root cause of your stress and frustration so that you can develop your own targeted coping strategies. Some examples include engaging in a hobby, listening to music, going on a walk or run, or simply practicing relaxation techniques. It is essential to experiment with various techniques and not be afraid to move away from ones that don’t work and toward ones that do.

The most important thing to remember is that retraining your brain is more of a marathon and not a sprint. It will include trial and error and open-mindedness, but if you focus on identifying your triggers and adapting your own coping strategies, it will almost certainly get better with time.

Seena Mathew, Assistant Professor of Biology, University of Mary Hardin-Baylor

This article is republished from The Conversation under a Creative Commons license. Read the original article.