Flies are undeniably annoying. Buzzing around your head, landing on your food, and generally disrupting the peace, they’re a common nuisance, especially during warmer months. This leads to all sorts of creative “solutions” to deter or eliminate them. One such enduring myth involves the humble penny. The idea is simple: place a bag of water with pennies in it near doorways or windows, and flies will supposedly stay away. But is there any truth to this popular fly control tactic? Let’s dive deep into the science, the folklore, and alternative methods to find out.
The Penny-in-a-Bag Theory: How Did This Start?
The origin of the penny-in-a-bag fly deterrent is murky, but the belief has been around for decades. There are several explanations offered for why it supposedly works.
The most prevalent theory revolves around light refraction. Proponents suggest that the water in the bag refracts light, creating a shimmering effect that disorients flies. This confusion, coupled with the metallic gleam of the pennies, is thought to overwhelm their compound eyes and make them steer clear. Flies possess compound eyes, which are made up of thousands of individual lenses called ommatidia. This allows them to detect movement extremely well, but it also makes them sensitive to light and shadows.
Another explanation connects the pennies to the flies’ perception of danger. Some believe that the reflected light and movement created by the water-filled bag mimic a spiderweb or a predator’s eyes, thus frightening the flies away. This would be an instinctive response designed to avoid potential threats.
Finally, some attribute the effect to the pure visual disturbance. They argue that the combination of light, movement, and the unusual appearance of the bag simply creates an environment that flies find undesirable. This is a more general explanation that doesn’t rely on specific biological or behavioral mechanisms.
Why the Penny-in-a-Bag Myth Doesn’t Hold Up
Despite its popularity, the scientific evidence supporting the penny-in-a-bag fly deterrent is virtually non-existent. Numerous experiments and anecdotal observations have failed to consistently demonstrate its effectiveness.
One of the main issues lies with the understanding of fly vision. While flies do have compound eyes and are sensitive to light, the idea that a simple bag of water and pennies could consistently disrupt their vision to the point of avoidance is highly questionable. Flies are incredibly adaptable creatures, and they quickly adjust to changes in their environment.
Furthermore, even if the light refraction did initially disorient them, flies would likely habituate to the effect over time. Habituation is a form of learning in which an organism decreases its response to a stimulus after repeated exposure. This means that even if the bag initially startled or confused the flies, they would eventually learn to ignore it.
Controlled experiments often show that flies land on surfaces near the bags, and sometimes even on the bags themselves. This behavior directly contradicts the claim that the bags are an effective deterrent. The visual complexity might momentarily pique their interest, but it doesn’t create a consistent barrier.
The lack of a controlled environment makes it difficult to isolate the penny-in-a-bag effect from other variables. Factors like wind, temperature, the availability of food sources, and the presence of other insects can all influence fly behavior. Without carefully controlling these variables, it’s impossible to definitively say whether the bag of pennies is actually having any effect.
The pluralistic ignorance phenomenon might also be playing a role. People might publicly endorse the belief in a penny-in-a-bag deterrent because they believe that others believe in it, even if they themselves have doubts. This can perpetuate the myth even in the absence of real evidence.
Understanding Fly Behavior: A More Effective Approach
To effectively control flies, it’s crucial to understand their behavior and biology. Flies are attracted to a variety of things, including:
- Food sources: Flies are attracted to decaying organic matter, such as garbage, food scraps, and animal waste.
- Moisture: Flies need water to survive, so they are drawn to damp areas, such as leaky pipes, standing water, and humid environments.
- Odors: Flies have a highly developed sense of smell and are attracted to certain odors, such as sweet smells, fermenting substances, and the smell of decaying meat.
- Light: Some flies are attracted to light, while others prefer dark and shady areas.
By understanding these attractions, you can take steps to eliminate or minimize the factors that draw flies to your home or business.
Proven Fly Control Methods: Beyond Pennies
Instead of relying on unproven methods like the penny-in-a-bag, consider these effective fly control strategies.
Sanitation: This is the most important step in preventing fly infestations. Keep your home clean and free of food scraps, garbage, and other potential food sources. Regularly clean garbage cans, compost bins, and pet waste areas.
Fly Traps: There are many different types of fly traps available, including sticky traps, light traps, and bait traps. These traps can be effective in reducing fly populations, especially when used in conjunction with other control methods.
Insecticides: Insecticides can be used to kill flies, but they should be used with caution and only when necessary. Always follow the instructions on the label and avoid using insecticides in areas where children or pets may be exposed.
Fly Swatters: A simple fly swatter can be an effective way to kill individual flies. This is a good option for dealing with small numbers of flies.
Screens: Install screens on windows and doors to prevent flies from entering your home. Make sure the screens are in good repair and fit tightly.
Professional Pest Control: If you have a severe fly infestation, it’s best to contact a professional pest control company. They have the knowledge and experience to effectively control fly populations and prevent future infestations.
Debunking Other Fly Control Myths
The penny-in-a-bag isn’t the only fly control myth out there. Here are a few others:
Essential oils: While some essential oils, like peppermint and eucalyptus, are said to repel flies, the evidence is mixed. Some studies have shown that these oils can have a repellent effect, but the effect is often short-lived and not as effective as other control methods.
Citronella candles: Citronella candles are often used to repel mosquitoes, but they are not as effective against flies. The smoke from the candles can help to mask the odors that attract flies, but it won’t kill them.
Dryer sheets: Some people believe that dryer sheets can repel flies, but there is no scientific evidence to support this claim. The strong scent of dryer sheets may be off-putting to some flies, but it’s unlikely to have a significant impact on fly populations.
The Real Reason Some People Think It Works
If the penny-in-a-bag doesn’t work, why do some people swear by it? There are a few possible explanations.
Placebo effect: The placebo effect is a phenomenon in which people experience a benefit from a treatment simply because they believe it will work. If someone believes that the penny-in-a-bag is repelling flies, they may be more likely to notice a decrease in fly activity, even if the bag is not actually having any effect.
Coincidence: Sometimes, a decrease in fly activity may coincide with the placement of the penny-in-a-bag, leading people to believe that the bag is responsible. However, this may simply be a coincidence. Fly populations fluctuate naturally, and there may be other factors at play that are not immediately obvious.
Other factors: People who use the penny-in-a-bag may also be taking other steps to control flies, such as cleaning up food scraps or using fly traps. These other measures may be the real reason for the decrease in fly activity.
Conclusion: Focus on Evidence-Based Solutions
While the penny-in-a-bag fly deterrent is a popular myth, there is no scientific evidence to support its effectiveness. Instead of relying on unproven methods, focus on evidence-based solutions, such as sanitation, fly traps, and insecticides. By understanding fly behavior and taking proactive steps to control their populations, you can enjoy a fly-free environment. Remember that effective fly control relies on consistent effort and a combination of strategies. Don’t waste your time on gimmicks; invest in methods that are proven to work. By taking these steps, you can keep your home or business free of these annoying pests and enjoy a more comfortable and hygienic environment.
Do pennies really kill flies?
The widely held belief that pennies kill flies is largely a myth, unsupported by scientific evidence. The premise is that copper in pennies somehow repels or poisons flies, but the concentration of copper exposed to the fly isn’t sufficient to have any noticeable effect. Flies are attracted to decaying organic matter, and a shiny penny lying nearby simply doesn’t register as a significant deterrent or threat.
Furthermore, modern pennies are primarily made of zinc with a thin copper coating. This means the actual amount of copper available to potentially repel flies is even less than in older, more copper-rich pennies. While cleanliness and proper food storage are effective fly control methods, relying on pennies is an outdated and ineffective home remedy.
What are some effective methods to control flies?
Effective fly control relies on addressing their attraction and breeding sources. This includes maintaining cleanliness, promptly cleaning up spills and food debris, and properly storing food in sealed containers. Regularly emptying and cleaning garbage cans is also crucial, as these are prime breeding grounds for flies.
Beyond sanitation, physical barriers like screens on windows and doors prevent flies from entering your home. Fly traps, both commercial and homemade, can also be effective in capturing and reducing fly populations. In cases of severe infestations, professional pest control services may be necessary for comprehensive treatment.
Why do people believe pennies kill flies?
The persistence of the “pennies kill flies” myth likely stems from anecdotal evidence and a misunderstanding of fly behavior. People may have observed fewer flies in the presence of pennies and attributed it to the pennies themselves, without considering other factors like cleanliness or the flies simply moving elsewhere. The belief might also be rooted in an attempt to find a simple, inexpensive solution to a common nuisance.
Moreover, the shiny appearance of pennies might have initially been thought to disorient or deter flies, though there’s no scientific basis for this. The myth has been passed down through generations, reinforcing its perceived validity despite lacking empirical support. It serves as an example of how easily misinformation can spread, particularly when it offers a convenient fix.
What kind of environments attract flies the most?
Flies are particularly attracted to environments that provide food, moisture, and breeding opportunities. This includes areas with decaying organic matter like garbage, compost piles, and animal waste. Spilled food and sugary drinks also attract flies, as do damp areas where they can lay their eggs.
Furthermore, poorly maintained drains and sewers can harbor fly larvae and provide a breeding ground for adult flies. Warm temperatures accelerate the flies’ life cycle, making infestations more common during summer months. Therefore, addressing these environmental factors is key to preventing and controlling fly populations.
Are there any natural fly repellents that actually work?
Several natural substances have demonstrated some effectiveness in repelling flies. Certain essential oils, such as peppermint, eucalyptus, and lavender, have been shown to deter flies with their strong scents. These can be diffused in the air or diluted and applied to surfaces.
Additionally, herbs like basil, rosemary, and mint can be planted around the house to naturally repel flies. Combining these natural repellents with good sanitation practices can significantly reduce fly populations without relying on chemical insecticides. Remember that effectiveness may vary depending on fly species and environmental conditions.
What are the risks associated with having a lot of flies around?
Having a significant fly population presents several health risks. Flies can transmit various pathogens, including bacteria, viruses, and parasites, as they move between contaminated surfaces and food. This can lead to the spread of diseases such as salmonellosis, dysentery, and typhoid fever.
Furthermore, flies can contaminate food through direct contact or by depositing eggs on it. This can cause food poisoning and other digestive issues. In addition to health risks, a large number of flies can be a nuisance, causing discomfort and disrupting daily activities.
Can ultrasonic pest repellents effectively repel flies?
Ultrasonic pest repellents claim to emit high-frequency sound waves that are supposed to drive away various pests, including flies. However, there’s limited scientific evidence to support the effectiveness of these devices in repelling flies specifically. While some studies have shown a marginal effect on certain insects, the overall consensus is that ultrasonic repellents are generally ineffective for fly control.
Flies are adaptable creatures, and it’s unlikely that a simple ultrasonic sound would significantly disrupt their behavior or drive them away permanently. Effective fly control requires a multi-faceted approach, including sanitation, exclusion, and targeted treatments when necessary, rather than relying on unproven technology.