Scientists still don't know why DEET is such an effective bug repellent

Wearing tick repellent, covering up, and performing tick checks are the best Lyme prevention

Spraying repellents onto your clothes—and reapplying them—or donning impregnated bug-repelling clothes can help keep ticks away. Effective sprays include DEET, picaridin, or permethrin. Bug spray applied to the body should be applied on top of sunscreen, and only after the sunscreen has dried.

How bedbugs have evolved immunity against pesticides

Bedbugs, once nearly eradicated in the United States due to the use of pesticides like DDT, have made a resurgence, with New York being declared the most bedbug-infested city. The primary reason for the return is the evolution of resistance in...

How to have a bug-free backyard dinner

An entomologist’s advice for bug-free backyard barbecues, including tips on the use of chemicals and how fans are pretty effective at keeping bugs away.

Mosquito saliva acts as an anticlotting agent

The bug's piercing mouthpart, the proboscis, is actually several tubes—one for sucking, one for spitting. But the chemicals in its spit actually help its blood meal to flow, combating its victim's ability to clot at the puncture site.

How Disney World keeps out mosquitos

Disney World may have been built on a swamp, but it's nearly free from the annoyance of mosquitos. That hasn't been an easy task; Disney has worked with engineers and pest specialists on minimizing the invasive bugs through a variety of different methods. This Reader's Digest article breaks down how they've successfully kept the park free from these unwanted guests.

Genetics may account for nearly 67% of mosquito attractiveness

In a mosquito attraction study published in 2015, identical twins appeared equally attractive to mosquitoes in lab tests, whereas some nonidentical twins were far less likely to be bitten than their siblings. Other work related showed that body odor is also more similar between identical twins.

Dogs smell a lot of stuff we can't, including bed bugs and chemicals in electronic devices

In addition to identifying medical smells and tiny insects like bed bugs, dogs can also detect electronic storage devices. These tools often contain triphenylphosphine oxide, a chemical used to prevent overheating.

Why bacterial bioremediation may help counter the negative effects of past chemical solutions

Molecules such as DDT, a synthetic insecticide, and PFAS—"forever" chemicals used to make products resistant to heat, water, and grease—have historically been used across various industries but are now known to be harmful. Microbes that can convert some of these substances into nontoxic products, such as water and carbon dioxide, have already been identified, with ongoing research to find others.

Demystifying sunscreen

Sunscreen is helpful all year round. Experts argue a minimum level of protection is SPF 30. There are two kinds of sunscreen: mineral (a physical barrier) and chemical (absorbs UV light). No new sunscreen ingredients have been approved in the US in decades, so foreign products are common.

How we helped make Aedes aegypti mosquitoes such a problem

Mosquito genome sequencing data suggests that Aedes aegypti mosquitoes first started specializing on human blood around 5,000 years ago—when climates shifted and humans started domesticating plants in Africa and stored large amounts of water that may have attracted the bugs.

More than 20 mosquito-borne and tick-borne diseases are found in the US

Children, older adults, and people with compromised immune systems are at particular risk of poorer health outcomes from these diseases. But dog owners and outdoor enthusiasts are among those at particular risk of contracting these illnesses, which include Lyme disease, Zika, and the condition Alpha-gal Syndrome.

Billions of flies are being dropped from the sky

The US is dropping billions of sterile flies to stop a deadly parasite. Screwworm maggots eat animals alive, so scientists are collapsing the population by ensuring females can’t reproduce.

There's a West Nile virus prevention rap—and it's amazing

This catchy rap from biologist MC Bugg-Z and the Fairfax County government in Virginia walks people through prevention steps and the dangers of the virus, telling listeners to "rock" insect repellant and talking about the history of the disease in the US.

Ticks survived 27 years in a lab, including eight without food

Research published in 2022 set a new record for tick longevity. A group of adult African ticks that are normally found in eastern and southern Africa lived in a laboratory for 27 years, including eight without food. What's more, one of the females laid eggs at least four years after the last male died. Most ticks, on average, reportedly live for six months to three years.

Americans only became intolerant of body odor in the last century

Daily bathing only became a societal norm in the last century. Today, Americans routinely bathe and buy more deodorant than any other country, spending roughly $6 billion annually on odor-reducing products. The rise of industrialized soaps, deodorants, and antiperspirants—and extensive marketing around them—stimulated this demand.

Rachel Carson's 'Silent Spring' exposed the harmful effects of pesticides on food

The 1962 book warned against the use of DDT, a pesticide often sprayed over fields of crops, cautioning that it could be harmful if ingested in excessive amounts by humans. Some credit Carson’s book with inspiring the modern environmental movement and with encouraging the US to establish the Environmental Protection Agency in 1970 and ban the domestic sale of DDT in 1972. (Some readers may experience a paywall.)

Plants use physical and chemical defenses to protect themselves

Tree bark is difficult to chew and resistant to pathogens, while the waxy cuticle on the surface of leaves deters insects and microbes. Some plants possess thorns, spines, and prickles to discourage predators. Plant cells can also produce antimicrobial toxins or release compounds to alert parasitic wasps to lay eggs in attacking insects.

It took 14 years to deploy penicillin after its discovery

Despite its promise, US production of penicillin remained minimal in 1942—enough to treat fewer than 100 patients nationwide. Within two years, output expanded into millions of doses to supply troops for D-Day.

Synthetic pheromones may protect coral reefs by attracting their predators

Researchers in Australia and Japan have developed these nontoxic chemicals to attract crown-of-thorns starfish, which consume corals that make up the Great Barrier Reef. As of 2026, synthetic pheromones have been shown to be effective in lab trials, and future field trials will attempt to lure starfish into areas for mass removal.

Humans may be able to distinguish more than one trillion scents

That's according to one estimate published in 2014. This figure far exceeds earlier estimates of a human smelling ceiling around 10,000 odors. The newer figure is derived from experiments in which volunteers agreed to sniff varying scents. Researchers mixed odor components and had volunteers sniff the brews to detect subtle scent differences. (Some users may experience a paywall.)

This decongestant doesn't work, so why is it still for sale?

Over-the-counter decongestants powered by phenylephrine won't help those with stuffy sinuses find relief, according to current evidence. This 10-minute video explores why these useless medications are still for sale in the US. The decongestant...

There are lots of weird ideas about dinosaur extinction, like hungry, hungry caterpillars

One of the great historical puzzles is this: why did the dinosaurs go extinct? Whether an asteroid, poison plants, volcanos and climate change, or something else, it's still a mystery. Scientists have been debating this question for almost a hundred years. One insect scholar suggests that caterpillars are the culprits.

Merck developed MDMA in the early 1900s as part of its effort to create a blood clotting drug

The company's chemists were attempting to synthesize a substance that could compete with an existing patent for the best clot medicine of that time, hydrastinine. MDMA was the byproduct of that effort.

The theory of chemtrails originated from misinterpreting a US Air Force paper

The document proposed a future weather modification system to achieve military objectives, but clarified that such a system "does not reflect current military policy, practice, or capability." Past testing of biological and chemical weapons has accelerated conspiracies about streaks of condensation trailing aircraft to be harmful chemical agents.

Some North American bats can glow in the dark

After examining 60 museum specimens from six different species, scientists found that all of them emitted light after being exposed to ultraviolet radiation. Researchers are perplexed by this natural phenomenon and are currently unable to deduce the reason behind it.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Scientists have struggled to pin down Ebola's natural reservoir species for decades, but the available evidence suggests that it's very likely fruit and insect-eating bats found in Africa.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Between 10 million and 50 million people in the US develop rashes from poison ivy, poison sumac, and poison oak each year.

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Massive blooms of microscopic plankton called dinoflagellates produce the neon blue light seen in glowing tides.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

'Silent' fireworks have gained more interest in recent years as a quieter celebratory option.

Despite being favored by 87% of Americans, Congress does not have term limits.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

'Saturday Night Fever,' the 1977 film that introduced disco to the mainstream, was based on a fabricated magazine story.

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

US intelligence allegedly pursued more than 600 schemes to assassinate Cuban revolutionary Fidel Castro.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.