Walking along the path to your house, you see a honeybee crawling along the ground in front of you. Is there anything wrong with your deliberately treading on it? We have no compunction about cutting flowers or mowing grass. These are living things. Why is the case of honeybees any different?
If you are Rene Descartes, the great French philosopher of the seventeenth century, the answer is simple: there is no difference. Honeybees are natural automata, designed by Mother Nature, without any thoughts or feelings. So, go ahead, squish that bee! Descartes held the same view for dogs and sheep and indeed all living animals. They know nothing, they feel nothing, they want nothing. It’s a remarkable view. It’s even more remarkable that someone who was smart enough to invent modern analytic geometry could have held it. Descartes’ actions spoke even louder than his words. He participated in vivisections on dogs and he commented that if a dog is whipped while a song is played, the dog will whimper in time to the melody.
How could Descartes have taken such a monstrous position? Enter religion. Descartes was a Roman Catholic and he believed that the mind is a spiritual substance, unlike anything else in nature, made not of matter, but of consciousness. Since for Descartes, only humans can have souls, animals must lack minds and merely behave as if they have them.
This is a preposterous view, if ever there was one, roundly criticized by Voltaire in response to Descartes, and later dismissed by Darwin. But if dogs and sheep and mammals generally have feelings -- if furthermore they are intelligent -- then why not too honeybees? And if honeybees are intelligent creatures with feelings, shouldn't you tread carefully?
Honeybees have a million neurons crammed into a cubic millimeter. Their neural density is ten times greater than that of any mammal. They do remarkably well at tasks requiring intelligence. For example, bees were trained (via sugar water as a reward) to fly into long cylinders with a single entrance and then out of one of two exits between which the bees had to choose. The exits of these cylinders then led to further similarly shaped cylinders so that a maze structure was created at the end of which the reward was found. Where the branch point in a cylinder was colored blue, the bees had to turn right. Where it was colored green, the bees had to turn left. Amazingly, the bees managed to learn the blue-right, green-left rule so that when they were placed in a new, unfamiliar maze of cylinders, they could apply it and get to the reward at the end.
There is also an extraordinary variety in bee behavior based on sensory information. For example, bees use landmarks and celestial cues (such as the position of the sun) to navigate. They gather food by visiting hundreds of flowers one after another; they check out places for potential nests; they exchange information with one another about food and nest sites via ‘waggle dances’. They also can recognize patterns and they are highly sensitive to movements. Their olfactory sense is acute. They can identify orientations of items as such and respond to those orientations when present in new cases. For example, they can be trained to distinguish between horizontal and vertical black and white stripes and to transfer this distinction to things other than stripes.
So, there’s not much doubt that bees are intelligent. Still, do they have feelings? Is there anything it is like subjectively to be a honeybee? The answer to these questions seems to be ‘yes’.
In a recent experiment conducted by Melissa Bateson and Jeri Wright in 2011, honey bees, strapped into little harnesses to render them immobile, were trained to associate one odor with a sugary taste and another with a bitter and unpleasant taste (that of quinine). The former taste was a reward, the latter a punishment. When the first odor was presented after a training period, the bees uncoiled and extended their mouthparts. When the second odor was presented, they retracted them.
The experiment next made use of the fact that when people are anxious, they tend to see the glass half-empty instead of half-full. For example, if an anxious person hears the sentence, “The doctor examined little Emily’s growth,” she is less likely to conclude that Emily is okay and that it is just her height that the doctor is checking. In general, anxious people interpret ambiguous stimuli more negatively. This presumably is related to the biological function of anxiety. Anxiety arises naturally in potentially dangerous situations, ones in which it behooves its’ subjects to tread carefully, to play it safe.
In the case of the bees, what the experimenters did was to divide the bees into two groups, one of which was shaken vigorously for 60 seconds in the manner in which a hive might be shaken by a badger. If bees are capable of bad moods, this shaking should have sufficed to put them in one.
Within 5 minutes after the shaking, the two groups of bees were presented with in-between odors. It was discovered that the shaken bees were less likely to extend their mouthparts to try out the associated tastes than the unshaken bees. This was not because they were disoriented. When presented with the odor associated with the sugary taste, they extended their mouthpieces just as before. Rather they interpreted the ambiguous stimuli as more probably punishment than reward. They saw the glass as half-empty. Since pessimism is behavioral evidence that a dog or another person is anxious, why not too for bees?
Bateson and Wright also checked the shaken bees’ systemic neurotransmitter levels. The shaken bees’ serotonin and dopamine levels were diminished as they are in humans who are feeling anxious. Likewise with sheep, for example. Sheep with depleted serotonin levels judge ambiguous stimuli negatively.
What are we to make of this? It does seem that the shaken bees were in a negative emotional state caused by the shaking and that this state in turn caused both stress-related physiological changes and a pessimistic cognitive bias, just as the experience of anxiety does in humans. But do they feel anxiety or distress?
Well, either the bees have been made anxious by the shaking or they haven’t. If they have, as Bateson and Wright claim, then they feel anxious; for occurrent anxiety is a feeling.
Of course, someone can be anxious without, at a particular moment, feeling anxious, but that is because the anxiety is dispositional, a disposition to feel anxious. The experiment does not show that bees are generally anxious creatures. What it shows (arguably) is that they can be made to be anxious in a certain setting. And if they are genuinely anxious in that setting, they must feel anxiety then.
If this is right, if bees are genuinely intelligent and capable of feelings, then they should be treated with respect, just as dogs should. So, watch out where you place your feet! (For more, see chapter 8 of my Tense Bees and Shell-Shocked Crabs: Are Animals Conscious?, Oxford University Press, November 2016.)