HASor the last forty years (but really since I was 5 years old) I have been fascinated by insects and their ability to sting and cause pain. During graduate school to become an entomologist, I became interested in the cause of these bites… and how: how can such small animals cause such suffering?
To answer my questions, you first had to find a way to measure pain. So I invented the insect pain scale. This scale is based on evaluations made on the basis of about a thousand stings that I personally received from Hymenoptera (wasps, ants, etc.) belonging to more than 80 groups of insects, as well as on evaluations by various colleagues.
Why do insects bite? The protection provided by bites opens the door to additional food resources, allowing them access to larger territories and social life in colonies. And the study of biting insects also allows us to better understand our own way of life, as well as the societies in which we live.
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A dart, a deadly weapon
To say that insects sting “because they can” doesn’t really answer the question… It’s important to understand why insects end up with stings.
Obviously, this organ was of some interest, otherwise it would never have appeared in the course of evolution – or, if it had been there in the first place, it would have disappeared due to the effect of natural selection.
The sting has two main purposes: to get food and not to become food for another animal. Examples of using stingers for food include parasitic wasps that sting and paralyze caterpillars that become food for young wasps, or bulldog ants that sting difficult-to-control insects into submission.
More importantly, the sting is a major advance in defense against large predators. Imagine for a moment that you are a medium-sized insect attacked by a predator a million times your size: without a stinger, what chance would you have of escape?
Honey bees face this problem along with honey-loving bears. Biting, scratching or kicking does not work… Stinging with a stinger injecting painful poison is much more effective.
In this sense, the biting insect has found a way to overcome the problem associated with its small size. The sting is a kind of “insect gun” that neutralizes the difference in size between the aggressor and the victim.
Insect bite pain index
This is where my insect bite pain scale comes into play, as it takes into account the duration of the bites, the type and intensity of pain they cause, and more.
Indeed, without numbers to compare and analyze, the injection experience is just a collection of anecdotes and stories worth telling. With numbers, on the other hand, we can compare the “pain protection” effectiveness of one biting insect versus another, and thus test hypotheses. [les descriptions de l’auteur sont aussi très imagées, pour faciliter le ressenti, NDLR].
One of these hypotheses is that painful bites are a way for small insects to protect themselves (and their young) from larger predators such as mammals, birds, reptiles or amphibians. The stronger the pain, the more effective the protection.
Better protection allows insects to form groups and develop into complex societies, as we see in ants, social wasps and bees. The greater the pain, the more society can evolve. And large corporations have advantages that individuals or smaller corporations do not.
Wasp stings are among the most painful Pepsi (also called “Tarantula hawk” in English, literally “tarantula hawk”, because it hunts spiders). However, this only lasts for a few minutes until the pain is caused by the ant’s venom Paraponera (or “rifle bullet” ant) causes a similar level of pain but can last up to 24 hours!
Human societies and insect societies
Human sociality allows some individuals to specialize and thus become able to perform a specific task better than most of their relatives. People specialists include plumbers, cooks, doctors, farmers, teachers, lawyers, soldiers, rugby players… and even politicians – a profession that is sometimes considered dubious but necessary for the functioning of society.
The societies that social insects form also have specialists who forage, care for young, defend the colony, reproduce, and even serve as gravediggers. Another advantage of forming societies is the ability to recruit other individuals so that they can use a large food source, create a common defense, or even get additional helpers for certain complex tasks.
Sociality also has a more subtle benefit: it reduces conflicts between individuals of the same species. Individuals who do not live in a social group tend to quarrel when they come into contact. But to live in a group, it is necessary to limit conflicts.
In many social animals, conflicts are mitigated by establishing a hierarchy. Often, if the dominant individual in the hierarchy is removed, fierce battles break out.
In human societies, conflict is also reduced by the establishment of hierarchy, but above all by laws, and by the establishment of a police force responsible for enforcing these laws; exchanges, discussions and learning also help inculcate cooperative behaviour.
In insect societies, the risk of conflict is reduced due to the establishment of hierarchy and pheromones (“smells” that identify individuals and their place in society).
What does pain tell us?
The insect bite pain index also opens a window into human psychology and emotions. In short, a person is fascinated by biting insects. We like to tell stories about bites, random incidents and even talk about our fear of insect bites.
Why? Because we have an innate fear of animals that attack us, be it leopards, bears, snakes, spiders or biting insects. People who do not experience this fear are more likely to be eaten or die after being bitten or bitten by a venomous animal. And therefore there is a greater risk of not passing on their genetic baggage than people who are more sensitive to this innate fear.
Biting insects scare us because they cause pain. Pain is our body’s way of telling us that damage is occurring, has occurred, or is about to occur. Damage is bad and impairs our ability to reproduce.
In other words, our emotional fear and our almost irrational fascination with insects whose bites are painful contributes to our long-term survival… All the more surprising that we have little fear of cigarettes or fatty and sugary foods, which kill far more people than said insects. .. One explanation for this difference between fatty and sweet foods is that our bodies have loved them for a long time – albeit in smaller amounts. The fear of these “killers” in a certain sense is not embedded in our genes…
The insect bite pain scale isn’t just “fun” (although it is). It allows us to better understand ourselves, how we evolved to get to where we are, and what we can expect from the future.
* Justin Schmidt, entomologist, Southwestern Biological Institute, University of Arizona.