It turns out that bees may not only be able to dish out pain — they can handle it.
In a study published last week in the journal: PNAS, researchers in the United Kingdom found that bees trade in heat exposure to access better food. The finding suggests that bees are not just mindless automata that respond to stimuli, but rather sentient, sentient creatures that can experience pain and engage in complex decision-making.
In other words, bees can be sensitive, which would mean they have the ability to sense and have subjective experiences.
Before the experiment, behavioral neuroscience PhD student Matilda Gibbons of Queen Mary University of London, along with four other colleagues, first offered bees the choice of drinking from two “high quality” feeders labeled yellow with a 40 percent sucrose (sugar) solution, equipped with an inactive heating pad. (Bees, like us, love sugar.) Several groups of bees were also offered two alternative pink-labeled feeders containing a 10, 20, 30 or 40 percent sucrose solution, each combined with a heating pad that was also inactive.
The bees naturally preferred the sweetest 40 percent sucrose solution. But researchers then repeated the experiment with a twist: The yellow sugary feeders were set at 131 F — enough to cause the bees discomfort, but no harm. The pink feeders, which ranged from 10 to 40 percent sucrose, were left unheated.
When the unheated feeder contained only 10 or 20 percent sucrose, the bees continued to drink from the sugar-rich feeders despite the pain. But when the unheated feeder contained 30 or 40 percent sucrose, many bees migrated to it, using associative memories to avoid the pain of the heated feeder while still being able to enjoy a high-sugar snack.
“Instead of being some kind of robotic reflexive response, where they would always avoid the heat in any situation, they’re able to weigh the different options and then suppress this response,” Gibbons said.
“Work like this recent article showing motivational compromises [and] strongly suggests that pain experience is in a sense quite revolutionary,” said Heather Browning, a philosopher and scientist in the London School of Economics’ Foundations of Animal Sentience project, who was not involved in the study.
One of the reasons it’s revolutionary, according to Browning, is because the ability to make motivational tradeoffs is an important marker in determining the feeling. It has also been observed in hermit crabs.
“At least one of the likely roles of the sense of an organism, one of the reasons that [sentience] evolved is to help an animal make such trade-offs,” Browning says. “It’s to help them have flexible decision-making when they have these competing motivations.”
However, it’s not formal evidence that bees are aware or that they feel pain, the researchers cautioned, given the inherently subjective nature of pain and awareness. Even understanding consciousness in humans is still a mystery, something known in philosophy as ‘the difficult problem’.
But the researchers do say that the possibility that bees can endure pain and suffering should be taken seriously, and the findings could apply to some other insects as well.
“Can we really say that just because bees do this tells us a lot about other insects? It probably applies to the closely related species, so bees and wasps and ants and maybe flies, but as you get further and further away, probably less,” says Andrew Crump, a postdoctoral biologist at the London School of Economics and a co-author of the research.
As revolutionary as the new study may be, it won’t usher in an insect rights revolution — just look at how we treat many birds and mammals despite general consensus about their sentiment.
Researchers are at the beginning of what will likely be a long slog to better understand whether, and how, insects are aware. But the findings serve as additional evidence that the number of species we include as sentient may be undercounted — and grossly so, given that there are an estimated 10 trillion insects alive at any given time (1 trillion is a million trillion).
The debate about who gets to sit in the Sentience Club
Despite the extraordinary evolutionary success of insects, animal science researchers have only begun to investigate whether they possess consciousness in recent years.
Until the late 1970s, researchers in the field focused on animal behavior, not trying to determine whether their behavior conferred consciousness. The animal mind—if such a thing existed—was thought of as a black box better left unopened.
That changed in large part through the work of Donald Griffin, a Harvard-trained zoologist who began to argue in the late 1970s that animals, not just chimpanzees and mammals, are conscious and that their minds need further study. His students began conducting animal studies, and the field, which he called “cognitive ethology,” grew from there.
The idea was controversial at the time, but today there is consensus among those who study the consciousness that birds and mammals can have feeling. While there are some outliers, there is also consensus that fish feel pain, which could be enough to indicate feeling. The jury is still out on insects, and probably will be for a while, but our understanding of them is changing.
“Social insects are traditionally thought to be completely instinctual: they can build complex nests and divide their work efficiently through innate behavior, but are considered stupid as individuals, with complexity arising only at the group level,” wrote Lars Chittka , a co-author of the study and author of The Spirit of a Bee, in the Washington Post. “But there is significant evidence that bees have an inner world of thought — that they don’t just respond to stimuli with tethered responses.”
Much of the debate over sensation has centered around the neocortex, the part of the mammalian brain that processes language, cognition, and more, and which most neuroscientists believe gives rise to consciousness. Crump says birds don’t have a neocortex, but a structure in their brain called the dorsal pallium is similar and is where scientists believe birds’ consciousness would lie.
Fish don’t have that brain structure either, but over the past two decades, researchers have come to believe that fish likely experience pain in the telencephalon region of the brain, which receives activity from their nociceptors — sensory receptors that identify and respond to harmful substances. incentives. We may be able to better understand insect life through similar discoveries, but it will be difficult to determine whether certain insect species are conscious, let alone all insects.
Much of the current focus of insect researchers is to find out what biological markers of feeling are, although the demonstrated ability to make motivational tradeoffs, as Gibbons’ bees did, is one of them.
The study builds on our understanding of insects’ ability to hurt, but it does not provide definitive evidence that bees or other insect species are conscious. However, if we use the precautionary principle – the idea that we must make the mistake of minimizing the damage in the face of limited information and uncertainty – let’s assume this is the case. Should that change the way we treat them?
Bees and other insects can feel pain. What now?
The debate over whether insects are sentient may seem frivolous, given the distance they feel from mammals, let alone humans. But any past debate about who deserves moral attention and how wide our circle of concern should be has seemed frivolous to some. If only a small fraction of the 10 trillion insects living today can feel pain, then perhaps some changes need to be made.
In light of this study, the most sensible place to start is beekeeping. According to Jason Schukraft, formerly of the Rethink Priorities research group (he now works at the grant-granting foundation Open Philanthropy), the trillions of bees managed for their honey worldwide can suffer from a variety of threats: exposure to pesticides, poor nutrition, disease, long-distance transportation, invasive hive inspections and honey harvesting. Those factors have been linked to colony collapse disorder, but they can be improved through better management.
Many cultures around the world have long eaten insects, but in recent years the insect farming industry has been on the rise – primarily to provide feed for factory-raised chicken and fish, rather than for direct human consumption. It’s an emerging trend that we might want to think twice about.
Getting more protein from insect farms instead of cattle, pig and chicken farms could be a victory for human health. But if commonly farmed insects like crickets and mealworms could feel pain, it could be a moral catastrophe worse than livestock farming, given the astronomical number of insects that would have to be reared to replace the more than 70 billion terrestrial animals. grown annually worldwide.
We can find ways to coexist with insects in a more humane way, such as reducing the use of insecticides at home and on farms. Policy makers might one day consider protecting insects by law as well. Earlier this year, the UK Parliament passed the Animal Welfare (Sentience) Bill, which covers all vertebrates; cephalopods, such as octopus and squid; and decapods, such as lobsters, shrimps and crayfish. For example, the law won’t ban shrimp farming, but it’s a sign that top government leaders are seriously considering the issue of animal awareness.
Crump says their recent study and future studies — when combined — could provide a clearer picture of whether bees and other insects are aware or not.
“It won’t be one study” [that determines insect sentience], and it won’t be some sort of indicator,” Crump said. Any development may provide only weak evidence for the sentiment, but if there are enough pieces all pointing to the same conclusion, Crump says, “That’s when we start to get a pretty strong case.”