Historically, it hasn't always been possible to grow fresh vegetables throughout the year.
Therefore, people developed methods of food preservation, such as pickling and fermentation — a process that uses enzymes to create chemical changes in food.
Kimchi is a traditional Korean dish made with salted, fermented vegetables. It typically contains cabbage and seasonings like sugar, salt, onions, garlic, ginger, and chili peppers.
It may also boast other vegetables, including radish, celery, carrot, cucumber, eggplant, spinach, scallions, beets, and bamboo shoots.
Though usually fermented for a few days to a few weeks before serving, it can also be eaten fresh, or unfermented, immediately after preparation.
Not only is this dish delectable, but it also offers many health benefits.
Here are 9 unique benefits of kimchi.
1. Nutrient Dense
Kimchi is packed with nutrients while being low in calories.
On its own, Chinese cabbage — one of the main ingredients in kimchi — boasts vitamins A and C, at least 10 different minerals, and over 34 amino acids.
Since kimchi varies widely in ingredients, its exact nutritional profile differs between batches and brands. All the same, a 1-cup (150-gram) serving contains approximately.
- Calories: 23
- Carbs: 4 grams
- Protein: 2 grams
- Fat: less than 1 gram
- Fiber: 2 grams
- Sodium: 747 mg
- Vitamin B6: 19% of the Daily Value (DV)
- Vitamin C: 22% of the DV
- Vitamin K: 55% of the DV
- Folate: 20% of the DV
- Iron: 21% of the DV
- Niacin: 10% of the DV
- Riboflavin: 24% of the DV
Many green vegetables are good sources of nutrients like vitamin K and riboflavin. Because kimchi often comprises several green veggies, such as cabbage, celery, and spinach, it's typically a great source of these nutrients.
Vitamin K plays an important role in many bodily functions, including bone metabolism and blood clotting, while riboflavin helps regulate energy production, cellular growth, and metabolism.
What's more, the fermentation process may develop additional nutrients that are more easily absorbed by your body.
Kimchi has an excellent nutritional profile. The dish is low in calories but packed with nutrients like iron, folate, and vitamins B6 and K.
2. Contains Probiotics
The lacto-fermentation process that kimchi undergoes makes it particularly unique. Fermented foods not only have an extended shelf life but also an enhanced taste and aroma.
Fermentation occurs when a starch or sugar is converted into an alcohol or acid by organisms like yeast, mold, or bacteria.
Lacto-fermentation uses the bacterium Lactobacillus to break sugars down into lactic acid, which gives kimchi its characteristic sourness.
When taken as a supplement, This bacterium itself may have several benefits, including treating conditions like hayfever and certain types of diarrhea.
Fermentation also creates an environment that allows other friendly bacteria to thrive and multiply. These include probiotics, which are live microorganisms that offer health benefits when consumed in large amounts.
In fact, they're linked to protection from or improvements in several conditions, including:
- certain types of cancer
- the common cold
- gastrointestinal health
- heart health
- mental health
- skin conditions
Keep in mind that many of these findings are related to high-dose probiotic supplements and not the amounts found in a normal serving of kimchi.
The probiotics in kimchi are believed to be responsible for many of its benefits. Nonetheless, more research is needed on the specific effects of probiotics from fermented foods.
Fermented foods like kimchi offer probiotics, which may help prevent and treat several conditions.
3. May Strengthen Your Immune System
The Lactobacillus bacterium in kimchi may boost your immune health.
In a study in mice, those injected with Lactobacillus plantarum — a specific strain that's common in kimchi and other fermented foods — had lower levels of TNF alpha, an inflammatory marker, than the control group.
Because TNF alpha levels are often elevated during infection and disease, a decrease indicates that the immune system is working efficiently.
A test-tube study that isolated Lactobacillus plantarum from kimchi likewise demonstrated that this bacterium has immune-enhancing effects.
Though these results are promising, human research is needed.
A specific strain of Lactobacillus found in kimchi may boost your immune system, though further research is necessary.
4. May Reduce Inflammation
Probiotics and active compounds in kimchi and other fermented foods may help fight inflammation.
For example, a mouse study revealed that HDMPPA, one of the principal compounds in kimchi, improved blood vessel health by suppressing inflammation.
In another mouse study, a kimchi extract of 91 mg per pound of body weight (200 mg per kg) given daily for 2 weeks lowered levels of inflammation-related enzymes.
Meanwhile, a test-tube study confirmed that HDMPPA displays anti-inflammatory properties by blocking and suppressing the release of inflammatory compounds.
However, human studies are lacking.
HDMPPA, an active compound in kimchi, may play a large role in reducing inflammation.
5. May Slow Aging
Chronic inflammation is not only associated with numerous illnesses, but it also accelerates the aging process.
Yet, kimchi possibly prolongs cell life by slowing this process.
In a test-tube study, human cells treated with kimchi demonstrated an increase in viability, which measures overall cell health — and showed an extended lifespan regardless of their age.
Still, overall research is lacking. Many more studies are needed before kimchi can be recommended as an anti-aging treatment.
A test-tube study indicates that kimchi may slow the aging process, though more research is necessary.
6. May Prevent Yeast Infections
Kimchi's probiotics and healthy bacteria may help prevent yeast infections.
Vaginal yeast infections occur when the Candida fungus, which is normally harmless, multiplies rapidly inside the vagina. Over 1.4 million women in the United States are treated for this condition each year.
As this fungus may be developing resistance to antibiotics, many researchers are looking for natural treatments.
Test-tube and animal studies suggest that certain strains of Lactobacillus fight Candida. One test-tube study even found that multiple strains isolated from kimchi displayed antimicrobial activity against this fungus.
Regardless, further research is necessary.
Probiotic-rich foods like kimchi may help prevent yeast infections, though research is in the early stages.
7. May Aid Weight Loss
Fresh and fermented kimchi are both low in calories and may boost weight loss.
A 4-week study in 22 people with excess weight found that eating fresh or fermented kimchi helped reduce body weight, body mass index (BMI), and body fat. Additionally, the fermented variety decreased blood sugar levels.
Keep in mind that those who ate fermented kimchi displayed significantly greater improvements in blood pressure and body fat percentage than those who ate the fresh dish.
It's unclear which properties of kimchi are responsible for its weight loss effects — though its low calorie count, high fiber content, and probiotics could all play a role.
Though the specific mechanism isn't known, kimchi may help reduce body weight, body fat, and even blood pressure and blood sugar levels.
8. May Support Heart Health
Research indicates that kimchi may reduce your risk of heart disease.
This may be due to its anti-inflammatory properties, as recent evidence suggests that inflammation may be an underlying cause of heart disease.
In an 8-week study in mice fed a high cholesterol diet, fat levels in the blood and liver were lower in those given kimchi extract than in the control group. In addition, the kimchi extract appeared to suppress fat growth.
This is important because the accumulation of fat in these areas may contribute to heart disease.
Meanwhile, a weeklong study in 100 people found that eating 0.5–7.5 ounces (15–210 grams) of kimchi daily significantly decreased blood sugar, total cholesterol, and LDL (bad) cholesterol levels — all of which are risk factors for heart disease.
All the same, more human research is needed.
Kimchi may lower your risk of heart disease by reducing inflammation, suppressing fat growth, and decreasing cholesterol levels.
9. Easy to Make at Home
Though preparing fermented foods may seem like a daunting task, making kimchi at home is fairly simple if you adhere to the following steps:
- Gather ingredients of your choice, such as cabbage and other fresh vegetables like carrot, radish, and onion, plus ginger, garlic, sugar, salt, rice flour, chili oil, chili powder or pepper flakes, fish sauce, and saeujeot (fermented shrimp).
- Cut and wash the fresh vegetables alongside the ginger and garlic.
- Spread salt in between the layers of cabbage leaves and let it sit for 2–3 hours. Turn the cabbage every 30 minutes to evenly distribute the salt. Use a ratio of 1/2 cup (72 grams) of salt to every 6 pounds (2.7 kg) of cabbage.
- To remove the excess salt, rinse the cabbage with water and drain in a colander or strainer.
- Mix the rice flour, sugar, ginger, garlic, chili oil, pepper flakes, fish sauce, and saeujeot into a paste, adding water if necessary. You can use more or less of these ingredients depending on how strong you want your kimchi to taste.
- Toss the fresh vegetables, including the cabbage, into the paste until all of the veggies have been fully coated.
- Pack the mixture into a large container or jar for storage, making sure to seal it properly.
- Let the kimchi ferment for at least 3 days at room temperature or up to 3 weeks at 39 F (4 C).
To make a version that's suitable for vegetarians and vegans, simply leave out the fish sauce and saeujeot.
If you prefer fresh over fermented kimchi, just stop after step 6.
If you choose fermentation, you'll know that it's ready to eat once it starts to smell and taste sour — or when small bubbles begin to move through the jar.
After fermentation, you can refrigerate your kimchi for up to 1 year. It will continue to ferment but at a slower rate due to the cool temperature.
Bubbling, bulging, a sour taste, and a softening of the cabbage are all perfectly normal for kimchi. However, if you notice a foul odor or any signs of mold, such as a white film atop the food, your dish has spoiled and should be thrown out.
Kimchi can be made at home using a few simple steps. Typically, it needs to ferment 3–21 days depending on the surrounding temperature.
Does kimchi have any downsides?
In general, the biggest safety concern with kimchi is food poisoning.
Recently, this dish has been linked to E. coli and norovirus outbreaks.
Even though fermented foods don't typically carry foodborne pathogens, kimchi's ingredients and the adaptability of pathogens means that it's still vulnerable to foodborne illnesses.
As such, people with compromised immune systems may want to practice caution with kimchi.
Although people with high blood pressure may have concerns about this dish's high sodium content, a study in 114 people with this condition showed no significant relationship between kimchi intake and high blood pressure.
Kimchi has very few risks. Nonetheless, this dish has been tied to outbreaks of food poisoning, so people with compromised immune systems may want to use extra caution.
The Bottom Line
Kimchi is a sour Korean dish often made from cabbage and other vegetables. Because it's a fermented food, it boasts numerous probiotics.
These healthy microorganisms may give kimchi several health benefits. It may help regulate your immune system, promote weight loss, fight inflammation, and even slow the aging process.
If you enjoy cooking, you can even make kimchi at home.
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By Bill Sullivan
Black licorice may look and taste like an innocent treat, but this candy has a dark side. On Sept. 23, 2020, it was reported that black licorice was the culprit in the death of a 54-year-old man in Massachusetts. How could this be? Overdosing on licorice sounds more like a twisted tale than a plausible fact.
The Root of the Problem<p>The unfortunate man who recently succumbed to excessive black licorice consumption is not alone. There are a smattering of similar case reports in medical journals, in which patients experience <a href="https://pubmed.ncbi.nlm.nih.gov/26380428/" target="_blank" rel="noopener noreferrer">hypertension crisis</a>, <a href="https://doi.org/10.5414/cn107011" target="_blank" rel="noopener noreferrer">muscle breakdown</a> or even death. Adverse reactions are most frequently seen in people over the age of 40 who are eating far more black licorice than the average person. In addition, they are usually consuming the product for prolonged periods of time. <a href="https://doi.org/10.1056/NEJMcpc2002420" target="_blank" rel="noopener noreferrer">In the most recent case</a>, the Massachusetts man had been eating a bag and a half of black licorice every day for three weeks.</p><p>Licorice is a flowering plant native to parts of Europe and Asia. Its scientific name, <em>Glycyrrhiza</em>, is derived from the Greek words "glykos" (sweet) and "rhiza" (root). The aromatic and sweet extract from its root has long been used as an herbal remedy for a wide variety of health maladies, from heartburn and stomach issues to sore throats and cough. However, there is <a href="https://www.fda.gov/consumers/consumer-updates/black-licorice-trick-or-treat" target="_blank">insufficient evidence to support that licorice is effective in treating any medical condition</a>.</p><p>Glycyrrhizin (also called glycyrrhizic acid) is the chemical in black licorice that gives the candy its signature flavor, but it also leads to its toxic effects.</p><p>Glycyrrhizin mimics the hormone <a href="https://www.yourhormones.info/hormones/aldosterone/" target="_blank">aldosterone</a>, which is made by the adrenal glands when the body needs to retain sodium and excrete potassium. Sodium and potassium work together as a kind of cellular battery that drives communication between nerves and the contraction of muscles. Too much glycyrrhizin upsets the balance of these electrolytes, which can raise blood pressure and disturb the heart's rhythm. Other symptoms of excessive licorice intake include swelling, muscle pain, numbness and headache. Examination of the man who died from consuming too much licorice revealed that he had <a href="https://doi.org/10.1056/NEJMcpc2002420" target="_blank" rel="noopener noreferrer">dangerously low levels of potassium, consistent with glycyrrhizin toxicity.</a></p><p><a href="https://doi.org/10.1056/NEJMcpc2002420" target="_blank" rel="noopener noreferrer"></a>It should be noted that a number of licorice-based foods do not contain real licorice, but use a flavoring substitute called anise oil, which does not pose the dangers discussed here. In addition, despite its name, <a href="https://www.livestrong.com/article/537724-black-licorice-vs-red-licorice/" target="_blank">red licorice rarely contains licorice extract</a>. Instead, red licorice is infused with chemicals that impart its cherry or strawberry flavor.</p><p>Products that contain real licorice are usually labeled as such, and list licorice extract or glycyrrhizic acid among the ingredients. Be advised that some products, such as black jelly beans or Good & Plenty, are mixtures of different candies that contain both anise oil and licorice extract.</p>
Hidden Dangers That Increase Risk<p>Glycyrrhizin has the distinct licorice flavor and is <a href="https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Licorice" target="_blank">50 times sweeter than sugar</a> and has been used in other types of candy, soft drinks, tea, Belgian beers, throat lozenges and tobacco. This can make it challenging to keep track of how much glycyrrhizin has been consumed, and a combination of these products could trigger adverse effects.</p><p>Some people take dietary or health supplements that already contain licorice, which increases the risk of toxic effects from eating black licorice candy. Certain medications such as <a href="https://doi.org/10.5414/cn107011" target="_blank">hydrochlorothiazide</a> are diuretics that cause increased urination, which can lower potassium levels in the body. Glycyrrhizin also lowers potassium levels, further disrupting the balance of electrolytes, which can produce muscle cramps and irregular heart rhythms.</p><p>People with certain preexisting conditions are more susceptible to black licorice overdose.</p><p>For example, patients who already have low potassium levels (hypokalemia), high blood pressure or heart arrhythmia are likely to have greater sensitivity to the effects of excessive licorice. Those with liver or kidney deficiencies will also retain glycyrrhizin in their bloodstream for longer times, increasing their risk of experiencing its adverse effects.</p>
What to Do?<p>If you're a fan of black licorice, there is no need to ban it from your pantry. Eaten in small quantities from time to time, licorice poses no significant threat to otherwise healthy adults and children. But it is advisable to monitor your intake.</p><p>With Halloween approaching, be sure to remind your kids that candy is a "<a href="https://www.heart.org/idc/groups/heart-public/@wcm/@global/documents/downloadable/ucm_305557.pdf" target="_blank">sometimes food</a>," especially the black licorice. The <a href="https://www.fda.gov/consumers/consumer-updates/black-licorice-trick-or-treat" target="_blank" rel="noopener noreferrer">FDA has issued warnings</a> about the rare but serious effects of too much black licorice, advising that people avoid eating more than two ounces of black licorice a day for two weeks or longer. The agency states that if you have been eating a lot of black licorice and experience an irregular heart rhythm or muscle weakness, stop eating it immediately and contact your health care provider.</p><p>Some scientists have further cautioned against the routine use of licorice in the form of a dietary supplement or tea for its alleged health benefits. A <a href="https://doi.org/10.1177/2042018812454322" target="_blank" rel="noopener noreferrer">review article from 2012</a> warned that "the daily consumption of licorice is never justified because its benefits are minor compared to the adverse outcomes of chronic consumption."</p>
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Material Revolutions: Shirts Made from Shellfish, Biodegradable Rum Bottles and Reusable Fast Food Containers
In the age of consumption, sustainability innovations can help shift cultural habits and protect dwindling natural resources. Improvements in source materials, product durability and end-of-life disposal procedures can create consumer products that are better for the Earth throughout their lifecycles. Three recent advancements hope to make a difference.
1. Allbirds Shirts Made From Shellfish<p>Sustainable sneaker start-up <a href="https://www.allbirds.com/pages/apparel" target="_blank">Allbirds</a> is known for its thoughtfulness for consumers and the environment. The four-year-old shoe company has become hugely popular by creating comfortable shoes made from responsibly sourced materials like tencel and wool, reported <a href="https://www.fastcompany.com/90565358/allbirds-new-clothing-line-includes-t-shirts-made-from-discarded-crab-shells" target="_blank">Fast Company</a>.</p><p>Recently, Allbirds launched its debut apparel line with garments for men and women made with eco-friendly materials that have a low carbon footprint, the report said.</p><p>Introduced along with the line is a new t-shirt material called "TrinoXO," which is made from wool and discarded snow crab shells from Canada's seafood industry, reported <a href="https://www.cnbc.com/2020/10/20/sustainable-sneaker-start-up-allbirds-is-selling-sweaters-t-shirts.html" target="_blank">CNBC</a> and <a href="https://www.cnn.com/2020/10/20/business/allbirds-sustainable-apparel/index.html" rel="noopener noreferrer" target="_blank">CNN</a>. The shells are the "number two discarded resource on earth," Allbirds claims, reported <a href="https://www.menshealth.com/style/a34427585/allbirds-apparel-clothing-line-review/" rel="noopener noreferrer" target="_blank">Men's Health</a>.</p><p>"Discarded material is the holy grail when it comes to sustainable fibers," Jad Finck, Allbirds head of innovation and sustainability, told Fast Company. "It's far better for the environment than getting raw materials from scratch."</p><p>The shells have antimicrobial properties that keep clothes fresh even after hours of wear, without the need to add "extractive" materials like zinc or silver, Men's Health reported. This allows for longer periods of wear between washes, reducing clothes' environmental footprint.</p><p>"We knew we wanted to be a real brand, and had this vision that we'd be an innovation company first, and a product company second," co-founder Joey Zwillinger told <a href="https://www.vogue.com/article/allbirds-launches-clothing" rel="noopener noreferrer" target="_blank">Vogue</a>. "And our products would solve problems for people in a natural way, and show the world that you don't have to compromise on the planet for amazing products."</p>
2. Bacardi Biodegradable Rum Bottles<p>By 2023, <a href="https://www.bacardi.com/us/en/" target="_blank">Bacardi</a> rum will be sold in 100% biodegradable bottles, <a href="https://www.businesswire.com/news/home/20201021005281/en/Bacardi-First-in-Fight-Against-Plastic-Pollution-With-100-Biodegradable-Spirits-Bottle" target="_blank">Business Wire</a> reported.</p><p>The alcohol giant is collaborating with Danimer Scientific, a leading developer of biodegradable products, to create the new bottles using the natural oils of plant seeds such as palm, canola and soy, the report said.</p><p>According to <a href="https://sports.yahoo.com/bacardi-to-make-100-biodegradable-spirits-bottle-124436841.html?guccounter=1&guce_referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce_referrer_sig=AQAAAE1Wl8ONNdph3ID8reylzGM8dbX575Mk96Jw6z3kHZaGjKCz_UgQgxH0Q1n3RNCzhOMBEZ7fAIf8iiOXLRtY9VVHNZsmb-w1VOJnGlzIbuwhmoBo_KOV4dba8FoWrkgmmwwCyQZnRoTL0Uda6HQ4pE5ewGWh2pwQzjS3gKAe1ynm" target="_blank">Yahoo Finance UK</a>, the new bottle will biodegrade in a wide range of environments, including compost, soil, freshwater and seawater. After 18 months, the bottle will disappear completely without leaving microplastics.</p><p>"Nodax PHA is one of the most promising eco-friendly materials in the world today because it delivers the biodegradability that consumers demand without losing the quality feel they receive from traditional plastic," said Danimer Scientific chief marketing & sustainability officer Scott Tuten, reported <a href="https://www.thrillist.com/news/nation/bacardi-biodegradable-spirits-bottle-plastic-free-packaging" target="_blank" rel="noopener noreferrer">Thrillist</a>. "The material provides the best of both worlds, and we look forward to working with Bacardí and incorporating PHA into their iconic packaging."</p><p>Bacardi is also creating a sustainably sourced paper bottle, Yahoo reported.</p><p>The manufacturing of both new bottle types will save energy over petroleum-based plastic ones. Bacardi plans to share the technology with competitors to help in the global fight against <a href="https://www.ecowatch.com/tag/plastic-pollution" target="_self">plastic pollution</a>, and aims to be 100% plastic-free by 2030, reported Thrillist.</p>
3. Burger King Reusable Fast Food Containers<p>Fast food giant <a href="https://www.bk.com/" target="_blank">Burger King</a> plans to launch reusable Whopper boxes and soda cups by next year. Partnering with TerraCycle's zero-waste packaging division Loop, Burger King will nudge customers to return the specialized packaging for hygienic washing and reuse, similar to how milk bottles used to be returned, reported <a href="https://www.marketwatch.com/story/can-burger-kings-reusable-packaging-change-fast-food-forever-11603392581" target="_blank">MarketWatch</a>.</p><p>"During COVID, we have seen the environmental impact of <a href="https://www.ecowatch.com/air-pollution-food-delivery-plastic-waste-2648454324.html" target="_self">increased takeaway ordering</a>, which makes this initiative by Burger King all the more important," said Tom Szaky, TerraCycle and Loop CEO, according to MarketWatch.</p><p>Customers who don't feel comfortable can opt-out of the service, <a href="https://www.abc10.com/article/entertainment/television/programs/the-buzz-burger-king-to-test-reusable-packaging-in-2021/77-f01f1b70-05b7-436d-9971-a7dd6081249b" target="_blank">ABC News</a> reported. Those who are willing to try will be charged a small deposit upon purchase, and when the packaging is returned, they will receive a refund, reported <a href="https://www.cnn.com/2020/10/22/business/burger-king-reusable-packaging-sustainability/index.html" rel="noopener noreferrer" target="_blank">CNN</a>.</p><p>Burger King and TerraCycle are aiming for a container that can be used at least 100 times, reported <a href="https://www.fastcompany.com/90566995/burger-kings-new-whopper-packaging-isnt-greasy-cardboard-its-reusable" rel="noopener noreferrer" target="_blank">Fast Company</a>.</p><p>"The benefit is, you're able to serve your guests without having to create that single-use item in the first place," Matt Banton, global head of innovation and sustainability at Burger King, told <a href="https://www.fastcompany.com/90566995/burger-kings-new-whopper-packaging-isnt-greasy-cardboard-its-reusable" rel="noopener noreferrer" target="_blank">Fast Company</a>. "This product is durable enough to go through the system multiple times, so it's ultimately reducing our environmental impact, and minimizing the amount of single-use packaging that we have to produce as well."</p><p>Burger King has also committed to sourcing 100% of its customer packaging from renewable, recycled or certified outlets, and recycling all customer packaging at its restaurants in the United States and Canada by 2025, reported CNN.</p>
There are many different CBD oil brands in today's market. But, figuring out which brand is the best and which brand has the strongest oil might feel challenging and confusing. Our simple guide to the strongest CBD oils will point you in the right direction.
The ghoulishly named ogre-faced spider can "hear" with its legs and use that ability to catch insects flying behind it, the study published in Current Biology Thursday concluded.
"Spiders are sensitive to airborne sound," Cornell professor emeritus Dr. Charles Walcott, who was not involved with the study, told the Cornell Chronicle. "That's the big message really."
The net-casting, ogre-faced spider (Deinopis spinosa) has a unique hunting strategy, as study coauthor Cornell University postdoctoral researcher Jay Stafstrom explained in a video.
They hunt only at night using a special kind of web: an A-shaped frame made from non-sticky silk that supports a fuzzy rectangle that they hold with their front forelegs and use to trap prey.
They do this in two ways. In a maneuver called a "forward strike," they pounce down on prey moving beneath them on the ground. This is enabled by their large eyes — the biggest of any spider. These eyes give them 2,000 times the night vision that we have, Science explained.
But the spiders can also perform a move called the "backward strike," Stafstrom explained, in which they reach their legs behind them and catch insects flying through the air.
"So here comes a flying bug and somehow the spider gets information on the sound direction and its distance. The spiders time the 200-millisecond leap if the fly is within its capture zone – much like an over-the-shoulder catch. The spider gets its prey. They're accurate," coauthor Ronald Hoy, the D & D Joslovitz Merksamer Professor in the Department of Neurobiology and Behavior in the College of Arts and Sciences, told the Cornell Chronicle.
What the researchers wanted to understand was how the spiders could tell what was moving behind them when they have no ears.
It isn't a question of peripheral vision. In a 2016 study, the same team blindfolded the spiders and sent them out to hunt, Science explained. This prevented the spiders from making their forward strikes, but they were still able to catch prey using the backwards strike. The researchers thought the spiders were "hearing" their prey with the sensors on the tips of their legs. All spiders have these sensors, but scientists had previously thought they were only able to detect vibrations through surfaces, not sounds in the air.
To test how well the ogre-faced spiders could actually hear, the researchers conducted a two-part experiment.
First, they inserted electrodes into removed spider legs and into the brains of intact spiders. They put the spiders and the legs into a vibration-proof booth and played sounds from two meters (approximately 6.5 feet) away. The spiders and the legs responded to sounds from 100 hertz to 10,000 hertz.
Next, they played the five sounds that had triggered the biggest response to 25 spiders in the wild and 51 spiders in the lab. More than half the spiders did the "backward strike" move when they heard sounds that have a lower frequency similar to insect wing beats. When the higher frequency sounds were played, the spiders did not move. This suggests the higher frequencies may mimic the sounds of predators like birds.
University of Cincinnati spider behavioral ecologist George Uetz told Science that the results were a "surprise" that indicated science has much to learn about spiders as a whole. Because all spiders have these receptors on their legs, it is possible that all spiders can hear. This theory was first put forward by Walcott 60 years ago, but was dismissed at the time, according to the Cornell Chronicle. But studies of other spiders have turned up further evidence since. A 2016 study found that a kind of jumping spider can pick up sonic vibrations in the air.
"We don't know diddly about spiders," Uetz told Science. "They are much more complex than people ever thought they were."
Learning more provides scientists with an opportunity to study their sensory abilities in order to improve technology like bio-sensors, directional microphones and visual processing algorithms, Stafstrom told CNN.
"The point is any understudied, underappreciated group has fascinating lives, even a yucky spider, and we can learn something from it," he told CNN.
In 'Road Map for a More Sustainable Future,' NY Regulator Tells Banks to Consider Climate Risks in Planning
By Brett Wilkins
Regulators in New York state announced Thursday that banks and other financial services companies are expected to plan and prepare for risks posed by the climate crisis.