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#39 What about insects? Do they have rights too?

#40 Do I have to be careful not to walk on ants?

#41 There is some evidence of consciousness in insects; aren't you descending to absurdity to tell people not to kill insects?

#42 Isn't it hypocritical to kill and eat plants?

#43 But how can you prove that plants don't feel pain?

#44 Aren't there studies that show that plants can scream, etc.?

#45 But even if plants don't feel pain, aren't you depriving them of their life? Why isn't that enough to accord moral status to plants?

#46 Isn't it better to eat animals, because that way you kill the least number of living beings.

#47 Nature is a continuum; doesn't that mean you cannot draw a line, and where you draw yours is no better than where I draw mine?

#39 What about insects? Do they have rights too?

Before considering the issue of rights, let us first address the question "What about insects?". Strictly speaking, insects are small invertebrate animals of the class Insecta, having an adult stage characterized by three pairs of legs, a segmented body with three major divisions, and usually two pairs of wings. We'll adopt the looser definition, which includes similar invertebrate animals such as spiders, centipedes, and ticks.

Insects have a ganglionic nervous system, in contrast to the central nervous system of vertebrates. Such a system is characterized by local aggregates of neurons, called ganglia, that are associated with, and specialized for, the body segment with which they are co-located. There are interconnections between ganglia but these connections function not so much as a global integrating pathway, but rather for local segmental coordination. For example, the waves of leg motion that propagate along the body of a centipede are mediated by the intersegmental connections.

In some species the cephalic ganglia are large and complex enough to support very complex behavior (e.g., the lobster and octopus). The cuttlefish (not an insect but another invertebrate with a ganglionic nervous system) is claimed by some to be about as intelligent as a dog.

Insects are capable of primitive learning and do exhibit what many would characterize as intelligence. Spiders are known for their skills and craftiness; whether this can all be dismissed as instinct is arguable. Certainly, bees can learn in a limited way. When offered a reward from a perch of a certain color, they return first to perches of that color. They also learn the location of food and transmit that information to their colleagues. The learning, however, tends to be highly specialized and applicable to only limited domains.

In addition to a primitive mental life as described above, there is some evidence that insects can experience pain and suffering. The earthworm nervous system, for example, secretes an opiate substance when the earthworm is injured. Similar responses are seen in vertebrates and are generally accepted to be a mechanism for the attenuation of pain. On the other hand, the opiates are also implicated in functions not associated with analgesia, such as thermoregulation and appetite control. Nevertheless, the association of secretion with tissue injury is highly suggestive.

Earthworms also wriggle quite vigorously when impaled on a hook. In possible opposition to this are other observations. For example, the abdomen of a feeding wasp can be clipped off and the head may go on sucking (presumably in no distress?).

Singer quotes three criteria for deciding if an organism has the capacity to suffer from pain: 1) there are behavioral indications, 2) there is an appropriate nervous system, and 3) there is an evolutionary usefulness for the experience of pain. These criteria seem to satisfied for insects, if only in a primitive way.

Now we are equipped to tackle the issue of insect rights. First, one might argue that the issue is not so compelling as for other animals because industries are not built around the exploitation of insects. But this is untrue; large industries are built around honey production, silk production, and cochineal/carmine production, and, of course, mass insect death results from our use of insecticides. Even if the argument were true, it should not prevent us from attempting to be consistent in the application of our principles to all animals. Insects are a part of the Animal Kingdom and some special arguments would be required to exclude them from the general AR argument.

Some would draw a line at some level of complexity of the nervous system, e.g., only animals capable of operant conditioning need be enfranchised. Others may quarrel with this line and place it elsewhere. Some may postulate a scale of life with an ascending capacity to feel pain and suffer. They might also mark a cut-off on the scale, below which rights are not actively asserted. Is the cut-off above insects and the lower invertebrates? Or should there be no cut-off? This is one of the issues still being actively debated in the AR community.

People who strive to live without cruelty will attempt to push the line back as far as possible, giving the benefit of the doubt where there is doubt. Certainly, one can avoid unnecessary cruelty to insects.

The practical issues involved in enfranchising insects are dealt with in the following two questions. --DG

"I want to realize brotherhood or identity not merely with the beings called human, but I want to realize identity with all life, even with such things as crawl upon earth." --Mahatma Gandhi (statesman and philosopher)

What is it that should trace the insuperable line? ...The question is not, Can they reason? nor, Can they talk? but, Can they suffer?" --Jeremy Bentham (philosopher)

SEE ALSO: #22, #40-#41, #47

#40 Do I have to be careful not to walk on ants?

The Jains of India would say yes! Some of their more devout members wear gauze masks to avoid inhaling and killing small insects and microbes.

Regardless of how careful we are, we will cause some suffering as a side-effect of living. The goal is to avoid unnecessary suffering and to minimize the suffering we cause. This is a far cry from wanton, intentional infliction of cruelty. I refer here to the habit of some of pulling off insects' wings for fun, or of torching a congregation of ants for pleasure.

This question is an issue for the individual conscience to decide. Perhaps one need not walk around looking out for ants on the ground, but should one be seen and it is easy to alter one's stride to avoid it, where is the harm in doing so? --DG

SEE ALSO: #39, #41

#41 There is some evidence of consciousness in insects; aren't you descending to absurdity to tell people not to kill insects?

Enfranchising insects does not mean it is never justifiable to kill them. As with all threats to a being, the rule of self-defense applies. If insects are threatening one's well-being in a nontrivial way, AR philosophy would not assert that it is wrong to eliminate them.

Pesticides and herbicides are often used for mass destruction of insect populations. While this might be defended on the self-defense principle, one should be aware of the significant adverse impact on the environment, on other non-threatening animals, and indeed on our own health. (Refer to question #59 for more on the use of insecticides.)

It is not absurd to attempt to minimize the amount of suffering that we inflict or cause. --DG

"We should begin to feel for the flies and other insects struggling to be free from sticky fly paper. There are humane alternatives." --Michael W. Fox (Vice President of HSUS)

SEE ALSO: #39-#40, #59

#42 Isn't it hypocritical to kill and eat plants?

There is currently no reason to believe that plants experience pain, devoid as they are of central nervous systems, nerve endings, and brains. It is theorized that the main reason animals have the ability to experience pain is as a form of self-protection. If you touch something that hurts and could possibly injure you, you will learn from the pain it produces to leave it alone in the future. Since plants cannot locomote and do not have the need to learn to avoid certain things, this ability would be superfluous and evolutionarily illogical. Furthermore, the fact that plants may or may not be able to suffer doesn't justify causing pain and distress to animals like dogs, cows, rats, or chickens who we know are capable of suffering a great deal.

It would be hypocritical IF the same criteria or morally relevant attributes that are used to justify animal rights also applied to plants. The criteria cited by the AR movement are "pain and suffering" and being "subjects-of-a-life". An assessment of how plants measure up to these criteria leads to the following conclusions.

First, our best science to date shows that plants lack any semblance of a central nervous system or any other system design for such complex capacities as that of conscious suffering from felt pain.

Second, plants simply have no evolutionary need to feel pain. Animals being mobile would benefit from the ability to sense pain; plants would not. Nature does not gratuitously create such complex capacities as that of feeling pain unless there is some benefit for the organism's survival.

The first point is dealt with in more detail in questions #43 and #44. The general hypocrisy argument is discussed in question #4. --TA

SEE ALSO: #4, #39-#44

#43 But how can you prove that plants don't feel pain?

Lest we forget the ultimate point of what follows, let us not forget the central thesis of AR. Simply stated: to the extent other animals share with us certain morally relevant attributes, then to that extent we confer upon them due regard and concern. The two attributes that are arguably relevant are: a) our capacity for pain and suffering, and b) the capacity for being the "subject-of-a-life", i.e., being such that it matters to one whether one's life fares well or ill.

Both of these qualities require the existence of mental states. Also note that in order to speak of "mental states" proper, we would denote, as common usage would dictate, that such states are marked by consciousness. It is insufficient to mark off mental states by only the apparent presence of purposefulness or intentionality since, as we shall see below, many material objects possess purposeful-looking behaviors.

So then, how do we properly attribute the existence of mental states to other animals, or even to ourselves for that matter? We cannot infer the presence of felt pain simply by the presence of a class of behaviors that are functional for an organism's amelioration or avoidance of noxious stimuli. Thermostats obviously react to thermal changes in the environment and respond in a functionally appropriate manner to restore an initial "preferred" state. We would be foolish, however, to attribute to thermostats a capability to "sense" or "feel" some kind of thermal "pain". Even placing quotes around our terms doesn't protect us from absurdity.

Clearly, the behavioral criterion of even functional avoidance/defense reactions is simply not sufficient nor even necessary for the proper attribution of pain as a felt mental state.

Science, including the biological sciences, are committed to the working assumption of scientific materialism or physicalism (see "The Metaphysical Foundations of Modern Science", E. A. Burtt, 1924). We must then start with the generally accepted scientific assumption that matter is the only existent or real primordial constituent of the universe.

Let it be said at the outset that scientific materialism as such does not preclude the existence of emergent or functional qualities like that of mind, consciousness, and feeling (or even, dare I say it, free will), but all such qualities are dependent upon the existence of organized matter. If there is no hardware, there is nothing for the software to run on. If there is no intact, living brain, there is no mind. It should also be said that even contemporary versions of dualism or mind-stuff theories will also make embodiment of mental states dependent on the presence of sufficiently organized matter.

To briefly state the case, cognitive functions like consciousness and mind are seen as emergent properties of sufficiently organized matter. Just as breathing is a function of a complex system of organs referred to as the respiratory system, so too is consciousness a function of the immensely complex information-processing capabilities of a central nervous system. It is possible, in theory, that future computers, given a sufficiently complex and orderly organization of hardware and clever software, could exhibit the requisite emergent qualities. While such Compute rs do not exist, we DO know that certain living organisms on this planet possess the requisite complexity of specialized and highly organized structure for the emergence of mental states.

In theory, plants could possess a mental state like pain, but if, and only if, there were a requisite complexity of organized plant tissue that could serve to instantiate the higher order mental states of consciousness and felt pain.

There is no morphological evidence that such a complexity of tissue exists in plants. Plants lack the specialized structures required for emergence of mental states. This is not to say that they cannot exhibit complex reactions, but we are simply over-interpreting such reactions if we designate them as "felt pain".

With respect to all mammals, birds, and reptiles, we know that they possess a sufficiently complex neural structure to enable felt pain plus an evolutionary need for such consciously felt states. They possess complex and specialized sense organs, they possess complex and specialized structures for processing information and for centrally orchestrating appropriate behaviors in accordance with mental representations, integrations, and reorganizations of that information. The proper attribution of felt pain in these animals is well justified. It is not for plants, by any stretch of the imagination. --TA

The absurdity (and often disingenuity) of the plant-pain promoters can be easily exposed by asking them the following two questions:

1) Do you agree that animals like dogs and cats should receive pain-killing drugs prior to surgery?

2) Do you believe that plants should receive pain-killing drugs prior to pruning? --DG

SEE ALSO: #42, #44

#44 Aren't there studies that show that plants can scream, etc.?

How can something without vocal apparatus scream? Perhaps the questioner intends to suggest that plants somehow express feelings or emotions. This notion is popularized in the book "The Secret Life of Plants", by Tompkins and Bird, 1972. The book describes "experiments" in which plants are claimed to respond to injury and even to the thoughts and emotions of nearby humans. The responses consist of changes in the electrical conductivity of their leaves. The truth is, however, that nothing but a dismal failure has resulted from attempts to replicate these experiments. For some definitive reviews, see Science, 1975, 189:478 and The Skeptical Inquirer, 1978, 2(2):57.

But what about plant responses to insect invasion? Does this suggest that plants "feel" pain? No published book or paper in a scientific journal has been cited as indeed making this claim that "plants feel pain". There is interesting data suggesting that plants react to local tissue damage and even emit signaling molecules serving to stimulate chemical defenses of nearby plants. But how is this relevant to the claim that plants feel and suffer from pain? Where are the replicated experiments and peer-reviewed citations for this putative fact? There are none.

Let us, for the sake of argument, consider the form of logic employed by the plant-pain promoters:

premise 1: Plants are responsive to "sense" impressions.

premise 2: As defined in the dictionary, anything responsive to sense impressions is sentient.

conclusion 1: Plants are sentient.

premise 3: Sentient beings are conscious of sense impressions.

conclusion 2: Plants are conscious of sense impressions.

premise 4: To be conscious of a noxious stimuli is unpleasant.

conclusion 3: Noxious stimuli to plants are unpleasant, i.e., painful.

There is a major logical sleight-of-hand here. The meaning of the term "sentient" changes between premise 2 ("responsive to sense impressions") and premise 3 ("conscious of sense impressions"). Thus, equivocation on the usage of "sentient" is used to bootleg the false conclusion 3. There is also an equivocation on the meaning of "painful" ("unpleasant" versus the commonly understood meaning). --TA

If we can bring ourselves to momentarily assume (falsely) that plants feel pain, then we can easily argue that by eliminating animal farming, we reduce the total pain inflicted on plants, leading to the ironic conclusion that plant pain supports the AR position. This is discussed in more detail in question #46. --DG

SEE ALSO: #42-#43, #46

#45 But even if plants don't feel pain, aren't you depriving them of their life? Why isn't that enough to accord moral status to plants?

The philosophy of Animal Rights is generally regarded as encompassing only sentient creatures. Plants are just one of many non-sentient, living creatures. To remain consistent, granting moral status to plants would lead one to grant it to all life. It may be thought that a philosophy encompassing all life would be best, but granting moral status to all living creatures leads to rather implausible views.

For example, concern for life would lead one to oppose the distribution of spermicides, even to overpopulated Third world countries. The morality of any sexual intercourse could be questioned as well, since thousands of sperm cells die in each act. Also, the sheer variety of life forms creates difficulties; for example, arguments have been made to show that some computer programs--such as computer viruses--may well be called alive. Should one grant them moral status?

There are questions even in the case of plants. The use of weed-killers in a garden would need defending. And if killing plants is wrong, why isn't merely damaging them in some other way also wrong? Is trimming hedgerows wrong?

The problems raised above are not attempts to discourage efforts to develop an ethics of the environment. They simply point out that according moral status to all living creatures is fraught with difficulties.

Nevertheless, some people do, indeed, argue that the taking of life should be minimized where possible; this constitutes a kind of moral status for life. Interestingly, such a view, far from undermining the AR view, actually supports it. To see why, refer to question #46. --AECW
   SEE ALSO: #46, #59

#46 Isn't it better to eat animals, because that way you kill the least number of living beings.

There are at least two problems with this question. First, there is the assumption that killing is the factor sought to be minimized, but as explained in question #18, killing is not the central concern of AR; rather, it is pain and suffering, neither of which can be attributed to plants.

Second, the questioner overlooks that livestock must be raised on a diet of plant foods, so consumption of animals is actually a once-removed consumption of plants. The twist, of course, is that passing plants through animals is a very inefficient process; losses of up to 80-90 percent are typical. Thus, it could be argued that, if one's concern is for killing, per se, then the vegetarian diet is preferable (at least for today's predominant feedlot paradigm). --DG

SEE ALSO: #18, #28, #45

#47 Nature is a continuum; doesn't that mean you cannot draw a line, and where you draw yours is no better than where I draw mine?

Most people will accept that the diversity of Nature is such that one is effectively faced with a continuum. Charles Darwin was right to state that differences are of degree, not of kind.

One should take issue, however, with the belief that this means that a line cannot be drawn for the purpose of granting rights. For example, while there is a continuum in the use of force, from the gentle nudge of the adoring mother to the hellish treatment visited upon concentration camp prisoners, clearly, human rights are violated in one case and not the other. People accept that the ethical buck stops somewhere between the two extremes.

Similarly, while it is true that the qualities relevant to the attribution of rights are found to varying extents in members of the animal kingdom, one is entitled to draw the line somewhere. After all, society does it as well; today, it draws the line just below humans.

Now, such a line (below humans) cannot be logically defensible, since some creatures are excluded that possess the relevant qualities to a greater degree than current rights-holders (for example, a normal adult chimpanzee has a "higher" mental life than a human in a coma, yet we still protect only the human from medical experimentation). Therefore, any line that is drawn must allow some nonhuman animals to qualify as rights-holders.

Moreover, the difficulty of drawing a line does not by itself justify drawing one at the wrong place. On the contrary, this difficulty means that from an ethical point of view, the line should be drawn a) carefully, and b) conservatively. Because the speciesist line held by AR opponents violates moral precepts held as critical for the viability of any ethical system, and because some mature nonhumans possess morally relevant characteristics comparable to some human rights-bearers, one must come to the conclusion that the status quo fails on both counts, and that the arrow of progress points toward a moral outlook that encompasses nonhuman as well as human creatures.

In addition, it should be noted that when a new line is drawn that is more in step with ethical truth (something quite easy to do), in no way should one feel that the wanton destruction of non rights-holders is thereby encouraged. It is desirable that a moral climate be created that gives due consideration to the interests and welfare of all creatures, whether they are rights-holders or not. --AECW

The idea that a continuum makes drawing a line impossible or that one line is therefore no better than another is easily refuted. For example, the alcohol concentration in the blood is a continuum, but society draws a line at 0.10 percent for drunk driving, and clearly that is a better line than one drawn at, say, 0.00000001 percent. --DG

SEE ALSO: #22, #39-#41


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