While some people’s first reaction to seeing a spider might be to squish it or spray it, arachnologists and spider experts suggest that this is the exact opposite of what you should do.
It turns out that killing your eight-legged house guest might result in more bad than good.
Do Dead Spiders Attract MORE Spiders? Yes, some theories suggest that a dead spider’s presence will attract visitors, but it is not scientifically confirmed that this is always the case.
That being said, there’s way more to this than a simple answer paragraph. This article will answer this question in depth and explore some surprising behavours spiders have around each other. Even dead ones!
So let’s get into it…
Why do dead spiders attract more spiders?
Studies on this subject are relatively new, and unfortunately, there hasn’t been enough research to be 100% certain why some people believe that dead spiders attract other spiders. This means there are many MANY conflicting theories about why this happens (or if it even happens at all).
One fact that is easy for spider experts to agree on is that certain types of spiders DO eat their own kind. Some of these cannibal spiders are the Australian redbacks, daddy long legs, red-backed jumping spiders, Portia jumping spiders, and pirate spiders.
These are spiders that participate in cannibalism simply because they’re hungry and because they can.
Since spiders have no qualms against eating their own kind, it’s easy to assume that spiders would be attracted to the dead body because they’re looking to eat it.
Spiders are also known to be opportunists, so many arachnid experts believe that living spiders may be drawn to a dead spider because there is little competition in that area, giving them potential access to food.
What is Spider Cannibalism?
Yes, spider cannibalism is a thing! Especially during mating season. Black widow spiders are famous for this practice, which earned them their nickname, but contrary to popular belief, they are not the only spider species to take part in it.
It’s extremely common for all types of female spiders to eat their smaller male mates – sometimes before the mating season even begins. While some males try to escape, some are actually into it, voluntarily jumping into the female’s fangs.
Why this ritual is such an engrained part of spiders’ existence has been up for debate for years. This has resulted in countless conflicting theories as to why females eat their mates. These theories revolve around nutrition, size, and personality.
Some ideas explain that the act of eating the mate after copulation gives the female an extra boost in nutrition, ensuring that it will become pregnant. Other theories state that the male is simply eaten because he’s too small and too weak to fight off the female.
Some experts claim that the likeliness of a female to eat its mate depends on how aggressive her “personality” is. The more aggressive she is, the more likely she is to attack – probably before the mating even occurs.
What chemicals do spiders release when they die?
Another theory of this strange phenomenon is that spiders release chemicals when they die. This chemical, or pheromone, is theorized to alert all other spiders of danger in the area.
This is also a common practice in bees, who have a built-in “alarm system” that warns other bees of possible danger when one is harmed.
Because of the bees’ natural instinct to protect their queen, this usually results in some bees investigating the crime scene. So dead bees draw in live ones, and it is theorized that the same occurs with spiders.
Again, there is not a lot of research on this topic, so much is left to speculation, but this supposed death pheromone is believed to be similar to the pheromone that is released when a female is looking for a mate.
Do some spiders avoid the areas where a dead spider was found?
Yes and no.
There are many conflicting theories on whether or not spiders avoid corpses or areas of death. Since there isn’t much research on this subject, there is much room for debate.
While some arachnologists believe that killing a spider will draw others in, some believe that killing a spider will result in an evolutionary improvement in which future generations of arachnids will learn to avoid areas in which their ancestors died.
These two conflicting theories have spider lovers divided down the middle. While many people swear by the belief that dead spiders attract other spiders, some question the evolutionary validity of that thesis.
Most species, humans included, tend to avoid areas that have been marked by death. Our natural will-to-live tends to push us away from activities that could result in harm, especially if those activities have hurt people we personally know. Some spider experts believe that it’s the same for spiders.
Do Spiders Play Dead?
Yes, believe it or not, spiders have been known to play dead.
If you’ve ever owned a pet spider, or know someone who did, you’ve probably heard of this a few times, but sometimes the little goofs pretend to be dead. Spiders will actually curl up into a little ball and stay completely still.
They can sit there for minutes, or even hours, without moving, which often tricks pet owners into thinking that their furry legged little friend died.
This act only happens when the spider is around a predator. By balling itself up and acting dead, their predator eventually loses interest in them and leaves, allowing the spider to jump and run to safety.
These little guys are so dedicated to their act that they won’t even react if they’re poked and prodded at. They’re the ultimate little actors, and if they do break character, it is because they believe that they’re life is in danger.
Why do Spiders’ legs curl up when they die?
We’ve all seen what happens when a spider dies. All its little legs curl up, and it turns into a little ball. This death curl is due to their unique anatomy. To move their eight, intricately designed legs, spiders actually use a type of hydraulic system.
This system relies entirely on the spider’s blood pressure and flexor muscles. There is a sudden increase in pressure, which shoots blood to their legs, allowing them to extend their legs as their flexor muscles relax.
Then the flexor tenses up again, allowing the spider to lift its leg, and the process starts over for every step they take.
Seems high tech, huh?
Because of this fancy little hydraulic system, spiders curl up into tight small balls when their bodies give out. Simply put, the system fails because there is no more hydraulic pressure keeping the flexor muscles relaxed. This causes these strong flexor muscles to constrict and retract, creating this ball shape.
Should you kill a spider that is in your home?
This leads us to the ultimate question: should you kill a spider that you find in your home? The general consensus says no. It would be best if you did not kill that spider you found hiding in the bathroom corner. Experts suggest that you let it go.
The main reason for this belief is that it does virtually no right to kill it. Despite the general opinion, spiders usually do not bite humans. Typical house spiders are not big enough to bite you, or even break your skin, and if a spider does bite you, it’s probably because your presence somehow threatened it (maybe you pinched it, crushed it, or startled it).
They’re not bloodthirsty creatures hell-bent on biting you – they are just trying to survive like everyone else.
Spiders do a lot of good for your homes by acting as the unofficial pest control. They will eat all small bugs within your home, which could end up saving you a lot of money and inconvenience in the future.
Beyond that, it’s not smart to go stepping on any spider that crosses your path. Every so often, you might come across a pregnant mother, and if you crush her, thousands of little spiders will come pouring out of her corpse, further infesting your house and giving you a disturbing sight that you won’t soon forget.
If you were frightened enough to kill one spider, it’s going to be a whole lot scarier when it brings in hundreds more. Though there are many conflicts on this alleged “myth” about dead spider attracting other spiders, it’s probably best to avoid it altogether.
The only time when it’s acceptable to kill a spider is when your home is overrun with them, and they’re a species of spiders that are dangerous to humans (black widows, brown recluse, yellow sac spider, mouse spiders, Sydney funnel webs, etc.)
In those extreme cases, it’s best practice to find a trained professional who can altogether remove all traces that the spiders left behind. We cannot say this enough; do not try to rid your house of spiders on your own.
If you enjoyed reading this article, then check out our piece on the colors of spiders, where we show the dizzying variety of spiders and their colors!
Though research in this area is highly limited, science has taught us one thing: it’s best to leave that spider alone. When you weigh all the pros and cons against each other, it’s easy to make the right choice. Let the spider be! Killing it might just attract more.
If you want to learn more about various insects, then checkout our site categories, we have a bunch of articles there that are totally worth reading:
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All the best
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