If you’re looking to improve your brain’s health, Korean university research is showing after dinner you should pass on chewing gum and start gnawing on your toothpick. Researchers at Kyungpook National University have found in a published study that the act of chewing increases blood flow and influences brain activity, along with finding that chewing wood could specifically improve your memory.
Previous studies concluded that chewing helped the brain given that it increases blood flow, allowing the brain to get more oxygen and nutrients quicker to help it function. However, the brain over time suffers through oxidative stress from reactive oxygen species, harmful molecules that damage brain cells. One way the brain protects itself from this stress is releasing antioxidants, which includes glutathione. Glutathione neutralizes these reactive oxygen species.
Chewing helps blood flow to the brain. Photo credit: Canva
The purpose of the research was to see if there was any difference in glutathione release levels during chewing and, if so, if there was any difference in what was being chewed. After various tests of cognitive function and glutathione measurement in 52 university students, half of which chewed gum for five minute spans and half of which chewed popsicle sticks for the same amount of time, the results were astonishing.
When it came to gum chewers, there didn’t seem to be any changes in glutathione levels and memory performance. However, those who chomped on popsicle sticks saw an increase in brain antioxidant levels, especially glutathione, and got higher scores on immediate memory and story memory tests.
While that’s some promising evidence, that doesn’t mean you should break out a 2×4 to nibble on for your next study session. Further research is needed since the testing group was limited to healthy 20-somethings and not a wide range of ages and certain health conditions. There would also need to be monitoring and testing of other sections of the brain, and testing with longer and shorter periods of chewing to confirm these findings.
But what are some proven ways to improve your memory while further tests on wood-chewing are done? Well, according to the Mayo Clinic and Harvard, the typical solutions are the standards: healthy diet, regular exercise, and quality sleep each night. Foods that happen to be good for the heart such as oily fish, leafy green vegetables, and nuts happen to be good for the memory, given that they promote more blood flow throughout the body including the brain. Same with cardiovascular exercise.
However, other methods to help keep your brain’s memory exercised include playing board games, doing puzzles, and playing word games, too. Go out of your way to play with or against other people, as being socially active further helps a person’s memory. There are also benefits to the memory if a person manages their stress levels and participates in regular meditation.While chewing gum doesn’t help improve your memory, there can be some other benefits. Chewing sugar-free gum is recommended by some dentists to strengthen your jaw muscles and teeth, along with cleaning your mouth. However, chewing gum as a TikTok fitness trend to get a squarer jawline has been frequently debunked, so there is no benefit to chewing extra-hard gum. In fact, you could injure your jaw and your teeth if you’re not careful.
Squinting through my binoculars, I scanned the dense branches of a black spruce, trying my best to catch a glimpse of the thin legs of a small black, white and yellow songbird. I was on the hunt for a yellow-rumped warbler – a bird affectionately called “butter-butt” by bird-watchers after the distinctive buttery yellow patch of feathers above its tail.
Stephanie Szarmach holds a yellow-rumped warbler that was banded as part of a study.Johanna Beam
Once I spotted a flash of red on one of the bird’s legs, I knew that this individual was special – in fact, it was one that I already knew well. That’s because I had placed identifying bands on it the previous year as part of my Ph.D. research, and it was carrying a very important piece of new technology.
I played the high pitched “warble” of its song through a speaker placed below a mist net of fine, nearly invisible mesh. Thinking another male had intruded on his territory, the bird quickly descended. My tactic worked – he got caught in the net. As I gently removed him, I breathed a sigh of relief as I saw the Tic Tac-size device sitting on his back.
A yellow-rumped warbler wears a multisensor geolocator backpack.Stephanie Szarmach
Over the past year, this warbler carried a multisensor geolocator backpack throughout his migratory journey, recording the long trek from his breeding grounds in Anchorage, Alaska, to a yet unknown winter refuge and back again. Working with my Ph.D. adviser, evolutionary biologist David Toews, I deployed dozens of these cutting-edge tags to illuminate the migratory journeys of these high-latitude breeding warblers at a scale not previously possible for small birds.
Now, after a year of waiting, I finally had the data in hand.
How can scientists track small birds?
Researchers began tracking the movements of migrating birds in the late 1960s using radio telemetry, a technique that requires tagged birds to be physically followed with receiver equipment, sometimes aided by a small aircraft.
Then, as GPS became more widely available in the early 2000s, satellite tags let researchers accurately track birds remotely. However, GPS transmitters are hefty – even just the battery that powers them is too heavy to be carried by the majority of small migratory songbirds, which often weigh less than a spoonful of sugar.
To address this problem, researchers developed ingenious little light-level geolocators. These miniature tags minimize weight by containing only a tiny battery, clock, computer chip and light sensor. They store data internally rather than transmitting it – hence my need to recapture tagged birds a year later. Researchers infer a bird’s locations from the timing of sunrise and sunset, which vary predictably across the globe and throughout the year.
Light-level geolocators have openednew windows into themigrations of small birds, but they also have limitations: Their estimated locations can err by hundreds of miles, and this uncertainty becomes impractically high around the equinoxes, when day length is the same worldwide.
Each harness loop of the multisensor geolocator goes around one of the bird’s legs and the tag sits on the bird’s lower back.Stephanie Szarmach
More recently, researchers developed a newer method of geolocation that uses atmospheric pressure to circumvent these limitations. When a bird ascends during a migratory flight, a barometric geolocator records a steep drop in air pressure, capturing the timing of departure and arrival for every stop along a bird’s migration route. In between flights, the pressure the tag records reflects the elevation at the bird’s position.
Knowing the bird’s elevation helps to narrow down possible locations, which researchers can then refine further by comparing the change in pressure over time recorded by the tag to global weather data using the computer program GeoPressureR. The unique pattern of rises and falls in pressure acts as a kind of pressure fingerprint for a specific location. Including light and wind data in the model of the bird’s movements can increase precision even more.
Atmospheric pressure data collected from a multisensor geolocator carried by a yellow-rumped warbler over five days in spring. When the bird is stationary, such as when resting at a stopover site, the measured pressure remains steady. During migratory flights, when the bird ascends into the sky, the pressure drops and fluctuates dramatically.Stephanie Szarmach
New tech answers an old question
We used these new multisensor backpacks to study the migration patterns of myrtle warblers, the northern subspecies of yellow-rumped warbler, which breed across North America’s boreal forest. Myrtle warblers in the northeast are known to winter along the Atlantic and Gulf coasts, but where northwestern populations migrate has been more of a mystery. In 1899, ornithologist Richard McGregor observed myrtle warblers wintering in coastal California, and hypothesized that these birds might breed in Alaska and British Columbia.
Using these new tags allowed us to test whether warblers breeding in Anchorage, Alaska, actually followed the shortest migration route to winter in California. To our surprise – and probably to McGregor’s as well, if he were still alive – we found that all the birds we tracked traveled east across the boreal forest of Canada before shifting south to the Gulf Coast – certainly not the Pacific Coast route we expected.
All told, this 6,800-mile (10,900-kilometer) round-trip journey was much longer than we anticipated for a species commonly considered a short- or medium-distance migrant.
Researchers tracked the routes six myrtle warblers flew on their fall migration southeast from Anchorage, Alaska.Figure by Stephanie Szarmach. Warbler illustration by Emily Griffith
Why take such a circuitous route?
The long, seemingly suboptimal route taken by our Alaskan myrtle warblers is actually mirrored by some other songbird species tracked from northwestern North America, including blackpoll warblers and Swainson’sthrushes.
Part of this pattern may relate back to the glaciations that isolated ancient populations of birds millions of years ago. The thinking goes that as these glaciers spread, they squashed the ranges of formerly northern species into the south. Then, as the glaciers slowly receded, the forests gradually reexpanded.
As more land opened up, birds moved farther north and west into that habitat. Each season some birds went a little farther as the forest available in their northern breeding grounds expanded. For migratory species such as myrtle warblers, the farther north and west their breeding range expanded, the longer the migration to their southern wintering ground became.
Scientists think migration routes are genetically encoded. The birds’ genes may have traced this expansion front, like Hansel and Gretel putting down breadcrumbs as they journeyed deeper and deeper into the forest. Today’s migration routes still trace that incrementally expanded path, even though the glaciers that shaped the original boundaries are long gone.
We’re still not sure exactly where the California-wintering myrtle warblers spotted in the 1800s are breeding. We suspect that a small proportion of the Anchorage-breeding birds may migrate to California, but that most of them travel from more distant, unstudied regions of Alaska or Yukon. Future research, potentially tagging myrtle warblers directly on the California wintering grounds, will shed more light on this population and why certain individuals follow a different migration route.
Barometric geolocation provides new data
Today, this new geolocation approach improves scientists’ ability to study the migrations of small birds and supports more effective conservation actions across the course of the entire year. More precise location estimates help researchers identify key stopover and wintering sites in need of protection and better understand the threats birds face throughout their journeys. These geolocators also reveal the altitude of migratory flights, which is important for understanding the risk of birds colliding with buildings or wind turbines.
Because these new tags capture pressure data for every migratory flight, they’re especially valuable for studying migration timing. Researchers have combined data from over 50 bird species to understand at what time of day or night different birds migrate. Now, as a postdoctoral researcher at the Smithsonian Migratory Bird Center, I am integrating multisensor geolocator data with satellite imagery to investigate how arrival and departure decisions throughout a bird’s migratory journey relate to seasonal changes in plant growth.
Scientists have now tracked dozens of bird species with multisensor geolocators, and that number increases every year. Each mapped migratory journey improves our understanding of how small birds migrate, what factors shape their movements and how best to protect them.
Fallen leaves shelter next spring’s pollinators and feed the soil. A horticulture specialist explains how to make room for both nature and a tidy yard.
Assistant Extension Professor of Horticulture and Ornamental Horticulture Specialist, University of Maine
Every autumn, homeowners and gardeners tend to engage in a familiar ritual. As trees shed their leaves, people drag out rakes, leaf blowers and lawn bags to strip their yards bare before winter arrives.
It is a tidy habit rooted in aesthetics, but ecologically, clearing away fallen leaves strips the very foundation of local ecosystems. Far from dead debris requiring disposal, this fallen foliage forms a dynamic layer and a biological interface that drives nutrient cycling and is essential for soil health and the environment, including biodiversity.
Here is the science behind why the first step of fall yard care could simply be doing less – along with practical ways to keep your yard looking neat while nourishing the ecosystem underneath.
A winter sanctuary for native pollinators
To understand why leaf litter matters, it helps to look closely at what happens beneath the surface as temperatures drop. While honeybees pass the winter in sheltered hives, the vast majority of North America’s native pollinators do not.
Raking, bagging and blowing leaves away destroys this crucial winter nursery.
Many other insects depend on the shelter of fallen foliage:
Moths and butterflies: Species such as the luna moth (Actias luna) and the Isabella tiger moth, whose caterpillar form is the woolly bear, spin cocoons or roll themselves directly inside fallen leaves. Raking or shredding those leaves destroys the next generation.
Fireflies: Adult fireflies lay eggs in moist soil, and their larvae spend up to two years hunting for their food, soft-bodied invertebrates under damp leaf litter. Raking deprives them of moisture and habitat.
In addition to being a shelter, fallen leaves are an evolved biological mechanism for nutrient cycling. Trees actively pump vital elements, including calcium, magnesium, potassium and nitrogen from deep subsoils, into their foliage. When autumn comes and leaves drop, these stored nutrients are deposited back into the soil.
Leaving leaves in place triggers fundamental ecological benefits.
A thick blanket of intact leaves acts as a natural insulator for the ground. Air pockets trapped between overlapping leaves moderate the soil temperature and slow heat transfer, buffering against the freeze-thaw cycles that heave soil, fracture plant roots and expose beneficial soil microbes to lethal cold. The intact leaf blanket also conserves moisture and prevents soil from drying out over the winter.
Adopting a softer approach to fall cleanup does not mean your yard has to look completely untamed or that you have to risk killing your lawn. Here is how to balance suburban expectations with sound ecological science:
Move, don’t remove: Move the leaves from lawns and sidewalks, rake them into garden beds, around ornamental plants or into vegetable plots, using manual rakes or electric leaf blowers. Aim for a layer 2 to 3 inches deep. Leaving leaves in grassy areas can help ticks hide there too, but if you move the leaves to garden beds or spots that are used less, the ticks will be less likely to nest in the grass. Establishing pollinator zones on the property can also help reduce tick populations.
Skip the leaf shredder: Mowing over leaves with a mulching mower is better than sending them to landfills, but high-velocity mower blades still kill overwintering insect eggs, chrysalises and larvae. Leave leaves intact wherever possible in plant beds.
Wait for spring to clean up: Do not cut back hollow-stemmed perennials or clear leaf beds during early, warm spring days. Wait until temperatures consistently stay above 50 degrees Fahrenheit (10 degrees Celsius) so overwintering bees and butterflies have time to safely emerge.
When you bag leaves for disposal and then buy commercial wood mulch or synthetic fertilizers in the spring, you are effectively paying a price for what your trees provided for free. By rethinking the cultural expectation of pristine autumn lawns, it’s possible to transform silent landscapes into vibrant habitat sanctuaries, simply by stepping back and allowing natural processes to take over.
The UN has passed a non-binding resolution to endorse the Equal Earth Projection, a map which more fairly represents the true size of the Earth’s landmasses. The current commonly used projection, called the Mercator Projection, greatly exaggerates land towards the north and south poles, which makes Africa look much smaller. In the Mercator projection, countries near the north and south pole can be anywhere from two to 14 times their true size. In the Equal Earth projection these distortions are minimised, making Africa look larger in comparison.
We asked Jack Swab and Derek Alderman, cartographers and geographers who study the social and communicative power of maps, to explain what’s going on.
What is a map projection?
A map projection is a technique that cartographers (map-makers) use to transform the round, three-dimensional Earth into a flat, two-dimensional map that we see on the wall or on our computer screen. As cartographers flatten the globe, the map becomes distorted, changing shapes and areas. There is no map projection that does not distort the Earth, but some projections are better suited for some uses than others.
A cartographer’s job is to choose from the hundreds of different map projections, and consider where the map is focused and how it is going to be used. No single projection is best for every use. This new Equal Earth projection is better suited than Mercator for producing global scale world maps for educational, public communication and policy purposes.
The Equal Earth supports a more accurate geographic understanding of the relative sizes of countries and continents. It provides a fairer perspective for the public to compare regions in terms of population, environment, development, politics and other global patterns.
Is the Mercator projection still useful?
While the Mercator projection isn’t good for showing the size of the Earth’s landmasses, we won’t see it totally disappear. For example, it’s very useful for navigational purposes as it maintains the accuracy of a compass bearing between two points without having to recalculate it.
This is why most online mapping platforms like Google Maps or Apple Maps rely on a variation of the Mercator projection to provide directions. Using the Equal Earth projection for navigation would not be as effective as the Mercator projection.
How will the Equal Earth projection be used?
Map-making is decentralised and there is no single authority regulating which map projection is used. What the UN did was endorse the broader message that Equal Earth is a fairer projection that more equitably displays the true size of the Earth’s land. And although this action is happening at a global level, there are movements underway in cartographic communities to make the Equal Earth projection the default world map projection.
The UN resolution by itself will not make Equal Earth a globally adopted projection. That requires intentional revision of maps used in textbooks, databases, media productions and diplomatic discussions, which requires labour and financial investment.
The Equal Earth projection was developed by cartographers and is a popular choice among map-makers since it was unveiled in 2018. It’s now possible to buy wall maps with the Equal Earth projection on them, and the projection has already been used in a wide variety of media. That said, individuals will need to opt in to using the Equal Earth projection over other types.
Why has the Equal Earth projection sparked resistance?
Resistance to the Equal Earth projection has been quite limited. There were several abstentions from the United Nations General Assembly vote, but most of this was for other reasons. Ukraine, for example, raised concerns over the depiction of the contested Crimean Peninsula on the map, which the Equal Earth Projection website depicts as contested territory.
This spurred a Russian response, along with points from other nations about contested territory. Given the UN resolution was a vote on how the world is portrayed and not about any specific political boundaries (a point that both Russia and Ukraine agreed on), these discussions amounted to geopolitical posturing about non-map issues.
The lone outlier, and only “no” vote against the Equal Earth projection, came from the United States. It claimed that the proposal was part of a “radical and ideological project” that was not appropriate for the United Nations to be debating. American delegates took issue with language linking Mercator’s distortions to colonial legacies and the marginalisation of Africa. This is not surprising since the current administration denies the existence of structural systems of inequality.
It is hard to miss the hypocrisy at play. The US wants other countries not to discuss the political implications of cartography even as President Trump engages in his own nationalist branding of the map. He has unilaterally renamed the Gulf of Mexico to the Gulf of America and Lake Ontario to Lake America for clear ideological reasons and without international consultation.
How does the new map matter when it comes to changing global views of the world?
The argument that African nations put forward was that the Equal Earth projection is a form of “cognitive justice”. Cognitive justice recognises that people often equate power and value of places with their apparent size on maps. Traditional views of Africa as a smaller continent compared to Europe or North America typically reflect the perceived importance of these parts of the world.
Equal Earth may make it easier to teach, broadcast and discuss a different view of Africa and its prominence in the world. Today, African countries are among the world’s fastest growing economies and fastest growing populations. Map projections alone cannot change people’s attitudes. Yet, as African nations seek to have more influence in international affairs, correcting the mental map of global leaders is an important step in amplifying the continent’s relevance and rights.
