The Demise Of Male Spiders After Mating – Do They Know?!

do male spiders know they will be eaten

Do male spiders know there end is nigh? Well the answer to this question starts with ‘it depends’.

Do male spiders know they’ll be eaten after mating? It turns out that some species of spider activity sense that their mate might want to make them into a quick meal and will actively defend themselves by wrapping the female in silk prior to copulation.

Keep reading and I’ll share with you some incredibly shocking and amazing behaviors that male and female spiders display during and after the mating process…

Some male spiders do know!

The answer to this question is that the species of spiders where the threat of cannibalism usually occurs before, during, or after copulation, appear in species with sexual dimorphism, where the females are generally more developed than the males.

But in some of these species, the males answer the question: do male spiders know they will be eaten? Some males know that they can be consumed by their mates and have evolved a defense mechanism to protect themselves against cannibalism.

For example the nursery spider (Pisaurina mira), which wraps the females in silk before copulation.

That being said, researching this article was a lot of fun. So I hope you’ll enjoy reading it as much as I did writing it…

It depends on the species of spider

Also, it is appropriate to mention that cannibalism does not usually occur in all situations where there is sexual dimorphism, as is the case of the black widow spider (Latrodectus mactans).

We mention this because although there is a belief that the female devours all her partners in this species, the truth is that most of the time, that does not happen. Even the male gets to live in the same web for some time with his beloved spider without suffering an attack.

The tale that sexual encounters between spiders are often dangerous for the male begins to change. The existence of a species of spider is documented where the females are victims of cannibalism by the male. Read on; we’ll talk a little more about it later.

Scientists at the Clemente Stable Biological Research Institute pay attention to male spiders’ mating with virgins while cannibalizing adult spiders with less reproductive success. These findings have been published in the London Linnean Society Journal of Biology, UK.

We will also talk about how cannibalism in some species of spiders after sex benefits their young. This is because, apparently, there is a cocktail of nutrients in the males that, in some “conscious” way, are usually sacrificed and offered as food so that the offspring are healthier.

All of this behavior occurs even after the first male comes to mate with a female, who has the best chance of fertilizing more eggs than subsequent suitors.

Are All Male Spider Species Eaten After Mating?

No not in all males of a spider species are eaten after mating. With the afore mentioned example mentioned above, “Pisaurina mira,” known as the nursery spider, the male wraps the females in silk before copulation. The roles begin to be reversed with the finding described above.

Another example where males are dominant, called “Allocosa brasiliensis.” This is a nocturnal spider, known as “wolf spider” or “tarantula,” that nests in dunes in South America, along riverbanks, and on the coast of the Atlantic Ocean in Uruguay.

There are spider species where the males carry out preventive measures by gagging their beloved cannibal companions (Pisaurina mira) before copulation, and another as the males (Allocosa brasiliensis) are the dominant ones and those who cannibalize adult females.

Why does this happen?

In the spider world, females are generally more developed than the males and are sex-selective, while the males are little travelers looking for potential mates.

In contrast, in the “Allacosa brasiliensis,” scientists found that the males are usually unusually dominant. Researchers were surprised by this fact, given that cannibalism has been widely documented in spiders during the mating process, and it is the first time that male spiders have been seen eating adult females.

The scientists observed that the males copulated more frequently with virgin spiders of good corporal condition, as a way to guarantee the success of the procreation.

They also evaluate the hypothesis that in this species, females younger physiques likely produce more eggs and, consequently, more “sons and daughters.”

They also describe the event as an “extreme sexual choice,” in which male spiders select whether to mate with females or eat them, an option that appears to be based on their mating potential.

The most valuable hypothesis is that males cannibalize females with less reproductive potential by using them as prey and mating only with females that ensure their reproductive success.

Why Does The Female Eat The Male? What Is The Benefit?

male spiders lay eggs

Studies show that cannibalism where the female eats the male is good for the young. There are species in which males execute different strategies to guarantee their lineage.

This is the case of the fishing spider (Dolomedes tenebrosus), which stands out as the most extreme of all, the male, to ensure an offspring, literally dies sacrificing himself to be a father.

This case also answers the question: do male spiders know they will be eaten? This species not only knows it, but they do it with a kind of conscience to preserve their offspring.

According to results published in Current Biology, the father’s sacrifice seems to increase the number, size, and chances of survival of his future offspring.

Females, almost twice the male’s size, cannibalize their mate and produce nearly twice as many spiders as those that did not have their post-sex dessert. Besides, the young grow about 20% more, and their life expectancy is around 50% more.

The scientists proved that it is not a question of food since they tried replacing the males with insects with similar characteristics and the results showed that there was a reduction in evolutionary patterns.

Considering all the above, the answer to the question: why does the female eat the male? Some do it to preserve the offspring in agreement with their partner, while other species that practice cannibalism probably does so because they confuse their partner and consider them a threat.

On the other hand, for the question: What is the benefit? The answer is that in addition to ensuring the offspring, it manages to increase their number and life expectancy.

According to the study, scientists indicate something unique about them, something special about males that makes it possible, such as a nutrient or a cocktail of nutrients concentrated in their bodies. Mother nature stuff!

Another curious fact is that the most cannibalistic females are also the most voracious towards their prey, and therefore, the best fed. This is surprising since they have more nutritional resources to invest in their offspring before finding the first males.

Is This Common For Other Types Of Insects?

The answer is yes. Sexual cannibalism in the animal kingdom is common for other types of insects, indeed, among arthropods. This behavior is studied by ethology as a variant of cannibalism characterized by occurring before, during, or after copulation.

For the most part, it is the female organism that kills and consumes the male of the same species, with reverse behaviors being rare.

Although cannibalism is usually a widespread behavior in many animal kingdom species, sexual cannibalism processes have only been documented in some species of insects, arachnids, and amphipods, also occur, although rarely verified among some gastropods and copepods.

Despite its significant frequency, this action is especially common in numerous lineages of spiders and scorpions. Its practice within a given population can significantly affect its size and the relative distribution of its members of different genera.

Among insects, sexual cannibalism is a particularly rare behavior, but it is practically widespread among different mantis species.

If you’re enjoying reading about spider behavior then we have a bunch of other articles exploring a whole host of questions and topics. Such as:

What Other Insects Have The Same Behavior?

There are other insects, for which sex is a matter of life and death. Such is the case with the praying mantis,scorpions, and bees.

Praying Mantis

do preying mantis eat hummingbirds

This insect is well known for its fondness for so-called sexual cannibalism. The females of this species usually eat their mates generally afterward, even during mating. According to a study, about 28% of female mantises’ will consume the male directly after mating.

This is a way of exhibiting greater strength to achieve mating, and incidentally, choosing the best-gifted consorts to fulfill the sexual ritual.

But what is the reason for this strange phenomenon? Apparently, by devouring the upper part of the body of its “beloved” partner, the mantis obtains a dose of protein necessary to lay more eggs once fertilized.


The practice of cannibalism is the first cause of mortality in these arachnids. It occurs practically during all stages of its existence.

During the reproduction season, in a population of scorpions, according to a scientific study, males have a mortality rate of around 60%, for two reasons:

  • The first is that they must move around a lot in search of females, risking finding more scorpions, with which they generally have to fight for life or death.
  • The second is that the males sometimes serve as food for the females in the mating process, ensuring a good meal that provides nutritional power to have a suitable litter.

Also, at birth, when they are more vulnerable because of their size and lack of defenses. The same scientific study has documented that the mortality rate in each litter reaches 65% in newborns.

Cannibalism is a natural phenomenon that regulates scorpion populations. The weakest are cannibalized so that only the strongest survive.

But all of the above occurs in only 38% of the species of 4 scorpion families. The other stage in which scorpions are also vulnerable is during and after molting because when they change their skin, it is difficult for them to move and defend themselves in case of attack.


Male bees in a hive ruled by a queen bee are known as drones, and they are born only with the primary mission of fertilizing the queen bee, after which they die since they donate their genital organs to her by detachment.

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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Steve Foster

Mad about bugs and wanting to publish as many articles as I can to help educate people about these amazing beautiful creatures! For more info check out my about page

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