The Exploitation of Insects and Why We Should Oppose It

Original text Luciano Carlos Cunha · Volume IV, p. 73 of the PDF edition · English translation

19.1. Are insects sentient?

There is a growing body of evidence of sentience in insects. Some examples of this evidence are given below. Since this is a class with an enormous diversity of species, a good number of them have not yet been studied with respect to their sentience. So the evidence below concerns studies carried out on a few species. However, we can generalize this evidence (at least in terms of the benefit of the doubt) to evolutionarily related species. This is because it is not that insects of other species were studied and failed to meet the criteria for sentience: what has happened is that they have hardly been studied at all.

Generalizing the conclusions reached for studied species to related species is already standard practice in recognizing sentience in other kinds of animals. For example, with respect to vertebrates, cephalopods, and crustaceans, the laws that mention their sentience are based on generalizations from the evidence obtained in intensively studied species to other related species¹⁵⁷. So there is no reason to proceed differently with respect to insects. This means we have reasons to treat all insects as sentient until proven otherwise.

Let us look, then, at some evidence of sentience in insects.

• Insect behavior is flexible, displaying decision-making in changing circumstances, adaptive behavior, cognitive generalization, and also learning that integrates different kinds of information¹⁵⁸.
• They have centralized nervous systems with distinct brains. Among the regions of their brains is the protocerebrum, which includes the so-called mushroom bodies, containing between one hundred thousand and one million neurons¹⁵⁹.
• Local field potentials (that is, electrical activity) with a response between 20Hz and 30Hz have been recorded in their brains¹⁶⁰.
• The connectome of some insects (that is, the map of their neural connections) is comparable to the fiber-tract networks found in primates, displaying so-called small-world organization (which consists of high connectivity between neighboring regions combined with shortcut connections to distant regions)¹⁶¹.
• Insects' mushroom bodies receive and integrate distinct multisensory information, enabling them to learn from previous experiences, remember them, and integrate information¹⁶², and they are thus a specialized center for processing spatial information and organizing movement¹⁶³.

This evidence seems more than sufficient for us, at the very least, to give insects the benefit of the doubt.

19.2. The exploitation of insects

The use of insects has grown enormously in recent years. Besides the exploitation of cochineal insects to produce dye, of silkworms to produce silk, and of bees to produce honey and other products, insects are increasingly being used directly for human consumption, often disguised as flours or burgers, and also to manufacture feed for other animals that humans also exploit¹⁶⁴.

Below are some figures on the annual deaths of insects in exploitation¹⁶⁵.

• Cochineal insects killed in the production of carmine dye: between 4.6 and 21 trillion¹⁶⁶.
• Insects killed for consumption: between 2 and 3.2 trillion¹⁶⁷.
• Silkworms killed for silk production: between 420 billion and 1 trillion¹⁶⁸.
• There are no data on the number of bees killed for honey production, but the population of bees kept for honey production is between 1.4 and 4.8 trillion individuals at any given time¹⁶⁹.

19.3. How insects are harmed in exploitation

The use of insects raises the number of animals killed to enormous levels. Since these animals are so much smaller, a vastly greater number of individuals is needed to produce the equivalent amount of meat or other product.

Moreover, they probably suffer a great deal throughout the whole process. The space allotted to insects on farms is even smaller, in proportion to their size, than that given to other animals¹⁷⁰. Before they are removed from confinement, the common practice is to deprive them of food for 12 to 24 hours and to lower the oxygen concentration. They are then kept alive and chilled to temperatures close to 0ºC. Typical methods of killing them are: freezing, immersion in water hotter than 80ºC, microwaving, infrared tunnel ovens, and grinding¹⁷¹.

19.4. Reasons to oppose the exploitation of insects

The first obvious reason to oppose the exploitation of insects is that it causes suffering and death to an enormous number of sentient beings. In addition, the exploitation of insects is unjust for the same reasons that the exploitation of any other sentient being is unjust. Below we will recapitulate three of these reasons.

First, like every practice in which there are exploiters and exploited, it violates the principle of equal consideration¹⁷² because it is biased in how it assigns weight to each individual's good.

Second, like every speciesist practice, it determines who will be benefited and who will be harmed on the basis of the species to which they belong. Species, like race and gender, is also a morally irrelevant property, since, besides being an outcome of the natural lottery (and therefore not resulting from merit or demerit), it does not determine whether someone can be harmed or benefited, nor the magnitude of the harms and benefits.

Third, it would never be approved if we did not know whether we would be born as humans or as insects. This shows that those who defend this practice do so only because they know they will not be its victims. If so, then it fails the impartiality test¹⁷³.

19.5. Responding to some objections

19.5.1. Are insects barely capable of suffering?

The exploitation of insects is sometimes defended on the grounds that animals with less complex brains are barely capable of suffering¹⁷⁴.

There are at least two ways of responding to this objection.

The first is to point out that, even if they were barely capable of suffering, they would still be seriously harmed by their exploitation, since they would still suffer and lose their lives. So even if they were barely capable of suffering, this seems insufficient to justify their exploitation.

The second is to deny that lower brain complexity implies that the individual is barely capable of suffering. The capacity to experience suffering and pleasure is a trait that prevailed in evolutionary history probably because it is directly connected to the motivation for behavior¹⁷⁵. That is, sentient beings avoid the stimuli that make them suffer and seek the stimuli that give them pleasure. This behavior, by increasing their chances of survival, also increases their chances of reproducing and passing this trait on. The point is this: the greater the cognitive capacities, the greater the diversity of

motivations for behavior and learning. So it is possible that beings with greater cognitive capacities can survive and pass on their genes even if they do not have very intense experiences of suffering and pleasure. On the other hand, the lower an animal's cognitive capacities, the more its motivation to act one way or another will be tied solely to the intensity of pain and pleasure¹⁷⁶.

This means that animals with lower cognitive capacities may quite possibly suffer even more intensely since, if this were not so, these species would most likely not have succeeded in passing on their genes and would no longer exist. Ryder (2002, p. 64) emphasizes this point: "Their experiences may be more simple than ours, but are they less intense? Perhaps a caterpillar's primitive pain when squashed is greater than our more sophisticated sufferings¹⁷⁷".

19.5.2. Are insects only slightly harmed by death?

It is sometimes argued that the more cognitively sophisticated experiences are, the more valuable they are, and that, for this reason, someone is harmed to a greater degree if they cannot experience them¹⁷⁸. Someone might want to appeal to this view to claim that nothing very bad is done to insects if they are killed, since they would not be capable of the intellectual pleasures humans are capable of.

However, what would have to be shown in order to maintain that beings with lower cognitive capacities are only slightly harmed by death is not that intellectual pleasures are more valuable, but that non-intellectual pleasures have almost no value. Yet when we think of all the non-intellectual pleasures we enjoy (being near those we love, going for walks, eating, having sex, swimming, and so on), it seems this could hardly be the case.

19.5.3. What if insects counted for less?

Let us suppose, for the sake of argument, that each insect should count for less than other sentient beings in our decisions. What would the implications be?

One might think that one implication is that the exploitation of insects would be justified. However, there is no such implication. It is one thing to be able to establish that certain individuals should count for less. It is another to be able to establish that we are justified in exploiting and killing the individuals who should count for less. An additional argument establishing this second conclusion would have to be put forward, since it does not necessarily follow from the first.

One might also think that if insects count for less, then we are justified in attaching little importance to trying to change their situation. But, again, there is no such implication. On the contrary: the number of them who suffer and are killed is so enormous that we should still keep protecting them as one of our priorities even if they counted for less¹⁷⁹. For example, suppose each human counted 1000 times more than each insect. This would mean that, for us to invest the same amount of resources in helping insects as we should invest in helping humans, there would have to be 1000 times more insects than humans in equally bad situations. Since in the real world the number of exploited insects is vastly greater than that, the balance would still tip toward giving priority to protecting them, even if each of them counted for much less.

19.6. What is the important conclusion to draw on this question?

If every sentient being matters, then the exploitation of insects (like that of decapods) is one of the most important problems there are, given the vast number of victims. This number is so large that this conclusion would hold even if there were justification for giving less weight to the good of each insect. Moreover, it is important to note that nothing we have seen shows that there is justification for giving less weight to the good of insects. If that is so, then the importance we should give to this problem is even greater¹⁸⁰.