Honey Bees on the Mind

ROSEMARY BUSH BLOOMING, buzzing with bees and birds, a reminder of controversies swirling around pollinators and beneficial insect species. The past Entomological Society of America (ESA) annual meeting featured outstanding virtual presentations on honey bees, bumble bees and pesticides with diverse lethal and sub-lethal effects on fertility, learning, memory, etc. A mindless rush to ban neonicotinoids (neonics, a class of pesticides developed originally in Japan to minimize deleterious effects on beneficial insects like honey bees) has resulted in increased use of worse pesticides (some capable of completely wiping out bee populations). Partly to blame are acutely dysfunctional Tier 1-3 regulatory processes hidden deep in the bureaucratic bowels of the EPA.

University of Texas, Austin researchers are among those leading the charge to have the EPA evaluate sub-lethal effects of all pesticides being considered as neo-nic replacements. Not just on honey bees, but also on bumble bees and other non-Apis native bees (includes lesser-known, less-social squash bees, that are important crop pollinators). Using field-realistic micro-colony experiments with bumble bees, Leeah Richardson found chronic, dose-dependent effects from flupyradifurone, a popular neo-nic replacement: At high concentrations, despite normal birth numbers, all bee larvae were dead by the third instar. In other words, normal numbers of bumble bee larvae were being born, but survival to adulthood was zero. But because adult bees survive flupyradifurone sprays, the pesticide is approved for use on open flowers. Thus, EPA policy (whether inadvertent, incompetent or otherwise dysfunctional seems to favor pollinator abortions before adulthood). Pollinator population control surely is not the goal? Perhaps to regulate otherwise would allow accusations of being pro-life, even if it means stopping abortion of pre-adult honey bees?

Regulatory bureaucracies typically have 3 tiers for evaluating agro-chemicals. Tier 1 is lab experiments with the active ingredient to determine the LD50 (lethal dose to kill 50% of the population). Tier 2 is semi-field experiments (e.g. field cages with treated and untreated flowers for comparisons and evaluation of sub-lethal effects). Tier 3 field trials are very rare, only conducted when Tier 1 and Tier 2 data are inconclusive. “Sub-lethal assessments on native bees, bumble bees, solitary bees really need to be carried out in the regulatory process in Tier 1 as a mandatory requirement,” said UT Austin’s Harry Siviter, who found no advantage from neo-nic replacements such as sulfoxaflor. “Otherwise we are just replacing one insecticide with others that have similar effects.” In other words, choosing winners and losers in the agro-chemical marketplace in an almost arbitrary, nonsensical manner. Welcome to Alice in EPA Land.

Lars Chitka’s new book, The Mind of a Bee (Princeton Univ Press, 2022), is stranger in some ways than Lewis Carroll’s Alice’s Adventures in Wonderland. “Understanding the minds of alien life-forms is not easy, but if you relish the challenge, you don’t have to travel to outer space to find it,” writes Chitka. “Alien minds are right here, all around you. You won’t necessarily find them in large-brained mammals—whose psychology is sometimes studied for the sole purpose of finding human-ness in slightly modified form. With insects such as bees, there is no such temptation: neither the societies of bees nor their individual psychology are remotely like those of humans. Indeed, their perceptual world is so distinct from ours, governed by completely different sense organs, and their lives are ruled by such different priorities, that they might be accurately regarded as aliens from inner space. Insect societies may look to us like smoothly oiled machines in which the individual plays the part of a mindless cog, but a superficial alien observer might come to the same conclusion about a human society. “

“Each individual bee has a mind,” writes Chitka. “That it has an awareness of the world around it and of its own knowledge, including autobiographical memories; an appreciation of the outcomes of its own actions; and the capacity for basic emotions and intelligence—key ingredients of a mind. And these minds are supported by beautifully elaborate brains. As we will see, insect brains are anything but simple. Compared to a human brain with its 86 billion nerve cells, a bee’s brain may have only about a million. But each one of these cells has a finely branched structure that in complexity may resemble a full-grown oak tree. Each nerve cell can make connections with 10,000 other ones—hence there may be more than a billion such connection points in a bee brain—and each of these connections is at least potentially plastic, alterable by individual experience. These elegantly miniaturized brains are much more than input-output devices; they are biological prediction machines, exploring possibilities. And they are spontaneously active in the absence of any stimulation, even during the night.”

“To explore what might be inside the mind of a bee, it is helpful to take a first-person bee perspective, and consider which aspects of the world would matter to you, and how,” writes Chitka. “I invite you to picture what it’s like to be a bee. To start, imagine you have an exoskeleton—like a knight’s armor. However, there isn’t any skin underneath: your muscles are directly attached to the armor. You’re all hard shell, soft core. You also have an inbuilt chemical weapon, designed as an injection needle that can kill any animal your size and be extremely painful to animals a thousand times your size—but using it may be the last thing you do, since it can kill you, too. Now imagine what the world looks like from inside the cockpit of a bee. You have 300 degree vision, and your eyes process information faster than any human’s. All your nutrition comes from flowers, each of which provides only a tiny meal, so you often have to travel many miles to and between flowers—and you’re up against thousands of competitors to harvest the goodies. The range of colors you can see is broader than a human’s and includes ultraviolet light, as well as sensitivity for the direction in which light waves oscillate. You have sensory superpowers, such as a magnetic compass. You have protrusions on your head, as long as an arm, which can taste, smell, hear, and sense electric fields. And you can fly.”

Honey bee research has been a source of inspiration and innovation, and many cite Karl von Frisch, celebrated for his research on bee dances as a form of communication. Von Frisch shared The Nobel Prize in Physiology or Medicine 1973 with Konrad Lorenz and Nikolaas Tinbergen “for their discoveries concerning organization and elicitation of individual and social behaviour patterns”. Thomas D. Seeley of Cornell University writes in the 2022 Annual Review of Entomology: “In the 1920s, Karl von Frisch described a forager producing this dance as follows: “[she makes] trembling movements forward and backward, and right and left”. The meaning of this strange behavior remained a mystery to von Frisch for more than 50 years, and near the end of his career he wrote, “I think it tells the other bees nothing. . .and perhaps is comparable to the condition that Florey has described as a neurosis”.

“I solved this mystery in the early 1990s when I discovered that a nectar forager produces a tremble dance when she visits a rich nectar source but then, upon returning home, has difficulty finding a bee willing to receive her nectar load,” writes Seeley. “The tremble dance calls bees to work as nectar receivers at the start of a nectar flow, just like the whistle atop a sardine factory in Maine calls villagers to work as sardine packers when fishing boats arrive laden with herring. It was thrilling to discover the meaning of this dance. Martin Lindauer once told me that Karl von Frisch had said that he would award a prize to whoever deciphered the message of the tremble dance. Alas, he died in 1982, nine years before I solved this puzzle. My studies of how a honey bee colony nimbly and wisely allocates its foragers among flower patches, despite never-ending changes in the locations of the richest ones, did lead to a different prize some years later. This bee work inspired two computer scientists at Georgia Tech to create the Honey Bee Algorithm (HBA). The HBA is widely used in internet hosting centers (analogous to hives) to optimally allocate webservers (analogous to foragers) among jobs (analogous to flower patches), so it is integral to the multi-billion-dollar industry of cloud computing. In 2016, the American Association for the Advancement of Science awarded me and four professors of engineering at Georgia Tech—John J. Bartholdi, Sunil Nakrani, Craig Tovey, and John Vande Vate—its Golden Goose Award. This award recognizes esoteric research that proves extremely valuable (i.e., that lays lots of “golden eggs”).”

In the German to English translation of his 1953 book, The Dancing Bees, Von Frisch wrote: “SUPPOSE German and English bees were living together in the same hive, and one of the Germans found a lot of nectar: its English companions would easily understand what it had to say about the distance and direction of the find…If we use excessively elaborate apparatus to examine simple natural phenomena Nature herself may escape us. This is what happened some forty-five years ago when a distinguished scientist, studying the colour sense of animals in his laboratory, arrived at the definite and apparently well-established conclusion that bees were colour-blind. It was this occasion which first caused me to embark on a close study of their way of life; for once one got to know, through work in the field, something about the reaction of bees to the brilliant colour of flowers, it was easier to believe that a scientist had come to a false conclusion than that nature had made an absurd mistake. Since that time I have been constantly drawn back to the world of the bees and ever captivated anew. I have to thank them for hours of the purest joy of discovery, parsimoniously granted, I admit, between days and weeks of despair and fruitless effort.”

As has been demonstrated time and time again, nothing is ever conclusively established and beyond challenge in science. Though for periods of time beliefs get set in stone until demolished (1,500 years in the case of some of Aristotle’s nature observations). In the 1920s and 1930s, Nobel Prize-winning immunologists and the American Medical Association doubted the existence of phages (viruses that kill bacteria) and prohibited research on the subject, until finally proven wrong with the invention of the electron microscope. Perhaps it will be the same with the much-contested CO2 climate change hypothesis, currently enthroned on a golden pedestal and considered beyond discussion. Change is a constant, as Adrian Horridge documents in his history of insect vision.

In his book, The Discovery of a Visual System: The Honeybee (CABI, 2019), Adrian Horridge, a honeybee researcher in the UK and Australia since at least 1945, puts forth his controversial history of honeybee visual research. “Beside this saga of contending personalities, this is in fact a serious book that attacks the detail and gist of the compound eye of a typical day-flying insect…The topic of this book is the much-needed revision that puts insect vision as exemplified by the bee, and dim-light vision in other insects, back on track. The new paradigm for visual inputs of the compound eye is one tonic colour blue and two derivatives that are rates of change in blue and green receptor channels. I hope that the novel prospect will be of interest to engineers of robot vision…There is universal inertia against innovation because it is expensive and requires thought, hard work and persistence, and then disrupts set ways. Forces for conformity are now a universal and growing danger that should be resisted. But worst of all, innovation implies an escape from bureaucratic control.” Indeed, insect optics research applied to fiber optics helps enable the World Wide Web and Internet to link computers worldwide at near the speed of light -a major global disruption of social patterns and cultures.

“Already, two major innovations of practical importance have emerged directly from our studies of insect vision,” writes Horridge. “In 1972, from the optics of fly eye, Allan Snyder discovered how the light gets into the light guides. The details were copied into the design of the fibres that carry light pulses for extreme distances in the World Wide Web (Chapter 4). In 1989, Srinivasan, Lehrer, Zhang and I discovered that insects detect a panorama of range by signals created by their own motion, not of objects, and Srinivasan later completed the installation of the resulting applications into mobile vehicles that fly with a computer on board (Chapter 9). The future will bring another important development: reverse engineering of insect vision, simply because insects are examples of extremely sophisticated and well-adapted visual mechanisms at exactly the right level of complexity to be copied into silicon for practical applications, quite unlike our own vision. Moreover, many neurons in an insect, perhaps all, are individually identifiable, and the wiring diagram is also constant, so that we can repeatedly return to precisely the same circuit, neuron or synaptic connection, with a variety of different techniques.”

“As yet, we have no firm circuitry or formal connections in the bee beyond cues and their coincidences,” writes Horridge. “The ways that preferences are established, modified and remembered remain a mystery. We have no idea how bees reach decisions. We have not identified the points where the layout of the two-dimensional image on the eye disappears into responses of line-labelled nerve cells, where odour signals are combined with vision, where traces of the image finally disappear in decisions such as ‘avoid’ and ‘attract’, or where meaningful visual cues are stored in memory. We do not even know whether memory is located at every synapse where the signal passes, or in special localized centres, or in both. A similar state of ignorance applies to every other animal brain, but the bee is one animal where progress is possible, perhaps with the aid of large tropical species.”