Vegans and vegetarians are being told “bad luck” in regards to a new study that has been headlining websites recently stating that “plants can hear themselves being eaten”
Is There Such Thing as Plant Sentience?
The 2014 study published in Oecologia journal specifically states that “..vibrations caused by insect feeding can elicit chemical defences”. Actually, this is nothing new. The effects of sound on plant growth and other traits have been recognised for decades. This same fact has also been warped and reused many times before as an implied opposition to veganism—where if plants have feelings too, then we might as well continue to also exploit and kill billions of animals across the plant every year (a number which doesn’t even include marine animals who are killed).
There is no study or research that shows that plants are subjectively aware.
While plants have evolved an array of traits that allow them to detect and react to damage from localised feeding insects, the confusion enters when the assumption of these chemical defences somehow translates that plants are subjectively aware. There is no study or research that shows that plants are subjectively aware.
A chemical reaction does not translate into the plant having some kind of conscious mind that desires not to be eaten. Importantly, a necessary condition of consciousness is sentient experience—there is no evidence to even remotely suggest that plants possess sentient experience. Science organises knowledge in the form of testable explanations and it can tell us that plants lack three fundamental elements for being regarded as sentient: sensory organs, basic variability of response and appetite, and locomotion. There are scientific studies have shown that plants can react to stimuli, however, this does not conclude to them being sentient. If a plant truly feels pain then that organism would possess the ability to alleviate that pain.
However, we know that animals can experience pain. Animals are sentient beings who have the ability to feel, perceive, and to experience subjectivity.
See More: What is Sentience?
Plants Are Complex Organisms
ome people speculate that plants are sentient as they are highly evolved and complex organisms that respond to their environment in surprising ways, especially across large time scales. Some plants react to insects by releasing deterrent or poisonous chemicals. Some plants react and release chemicals to deter other plants from growing near them. Some plants are either aggressive or passive in root development depending on whether or not they are around their own species. The Venus Flytrap catches and consumes insects when insects come in contact with tiny hairs that trigger the trap to close.
However, the confusion arises when the assumption is made that such plant behaviour is caused by the plants “subjectively experiencing the world through sense data”, rather than by insentient hormonal, electrical, mechanical, and chemical processes reacting to external stimuli.
The scientific principle of parsimony states that we shouldn’t postulate a complex explanation for phenomena when a simpler explanation will suffice.
When autonomic systems in mammals, such as the cardiovascular system, or the immune system, or the reproductive system at the level of the behaviour of sperm in the presence of an egg appear to be reacting ‘subjectively, consciously and intentionally’ to perpetuate either themselves or their host organism, we don’t just assume that these systems are sentient independently of their host organism and acting consciously. We recognise that there are insentient hormonal, electrical, mechanical, and chemical processes that cause various behaviours and events to take place.
The development of these insentient processes can be explained by tens and hundreds of thousands of years of natural selection and evolution, where hundreds of billions of small, genetic mutations and combinations survived or failed to survive based on how adaptive they were—the same principal of parsimony should be applied in the assessment of plant behaviour.
Plants do not have any of these neurological components to provide sentience and complex emotion.
Neuroscientists have positively confirmed the areas of our neurology (brain stem, limbic system, etc) that serve to provide sentience and complex emotion. All vertebrates and at least some non-vertebrate animals have these nervous system components, providing strong positive, empirical evidence that such beings are sentient, and that most of them have highly subjective, emotional lives. Plants do not have any of these neurological components to provide sentience and complex emotion.
As unconscious entities, plants have no subjective, conscious interest that would be morally relevant to whether we kill them for food or other sufficient reasons. We should respect plants in the same sense in which we respect the beauty, complexity, and wonder of insentient nature and natural phenomena in general, which entails reducing our impact on them as much as is reasonable, and not destroying them gratuitously. Our moral obligations regarding plants, however, do not compare in kind to our direct moral obligations to vertebrate animals, whose sentience and conscious, intentional striving for life and survival is incredibly obvious to us.
Given this eager striving for life and survival of sentient vertebrates, veganism is the minimum standard of decency.