Expanding Consciousness Bees and other insects show signs of possessing complex self-awareness, but if the scope of consciousness is widened, where will it end? Lars Chittka and Catherine Wilson onsciousness is a state of close to the notion of philosophical ous evening, and in the hours before awareness that allows us to zombies—hypothetical robots that be- sunrise, they communicated locations close our eyes and picture have overtly like normal humans, but visited on the former morning. our childhood home, or to are entirely based on preprogrammed These bees retrieved their spatial Cperform the sort of planning, predic- behavior routines and reflexes, with- memories entirely out of context, at a tion and risk assessment required to out any self-awareness. time at which there was no possibil- gauge whether it’s safe to jump over But there are now many indications ity of foraging and no need for com- a stream of a given width. It allows us that insects exhibit consciousness-like munication. The function is unclear— to solve problems by thinking, rather phenomena. Some lines of evidence are they may have spontaneously thought than simply by trial and error. from experiments that have lain bur- about these spatial locations during For centuries, scholars such as René ied in the literature for decades, even the night, or perhaps this communica- Descartes (1596–1650) have argued centuries, without anyone recognizing tion functioned as a strategy for spatial that consciousness is a uniquely hu- their significance for consciousness. memory consolidation. Later studies man attribute, perhaps facilitated by Honeybees, for example, have have shown that a bee’s memories of language, that allows us to communi- a symbolic language by which they the previous day become strengthened cate about our memories and feelings, communicate about the precise coordi- when they are exposed to elements of and to coordinate plans for the future. nates of floral food sources or potential these memories while they are deeply In this view, nonhuman animals were nest sites (see “Group Decision Making asleep. Perhaps bees dream about the regarded as merely cleverly-designed In Honey Bee Swarms,” May–June 2006). experiences of the previous day? automatons with a toolkit of pre- In this dance language, a scout bee re- The key implication in Lindauer’s programmed behaviors, each triggered turning from a flower patch performs discovery is that bees are capable of by certain environmental stimuli. a repetitive sequence of movements offline thinking about spatial locations Social insects such as bees and ants in the dark hive on the vertical comb. (and the ways in which the locations seemed to epitomize this viewpoint. These movements are keenly attended are linked to time), in the complete Scientists knew that a large behavioral by other bees. The successful forager absence of any external trigger—a repertoire is required to construct their moves forward in a straight line for conclusion which does not align with elaborate homes, defend them against a few centimeters, then a half circle the assumption that bees are zombies. intruders, provision their young with to the left back to her starting point. Bees, then, appear to have at least some adequate nutrition—but it seemed She performs another straight run, and of the principal hallmarks of conscious- plausible that these animals were then circles to the right. The duration ness: representations of time and space. nonetheless “reflex machines” without of the straight run tells other bees the internal representation of the world or distance to the food source (roughly The Evolution of Consciousness an ability to foresee even the immedi- one second of walking distance in the Based on such evidence, many biolo- ate future. In this view, insects were dance corresponds to a one-kilometer gists and philosophers now suspect flight to the target). The direction of that consciousness-like phenomena Lars Chittka is professor of sensory and behavioral this run relative to gravity encodes the might be evolutionarily ancient, per- ecology at Queen Mary University of London and direction relative to the Sun—for ex- haps dating back to the Cambrian Pe- the author of the forthcoming book The Mind of ample, if the run in the hive is straight riod (approximately 500 million years the Bee (2020). Catherine Wilson was most re- up, this tells other bees to fly in the ago). This line of inquiry might seem cently Anniversary Professor of Philosophy at the direction of the Sun. like a slippery slope. Where should we University of York and is now Visiting Presiden- Karl von Frisch made this discovery draw the line? Do plants have some tial Professor at the City University of New York in 1945, for which he was later award- form of awareness? Or, as panpsychists Graduate Center. Her recent book The Pleasure ed the Nobel Prize in Physiology or would argue, do electrons, rocks, com- Principle (2019) discusses, among other topics, Medicine. A decade later, one of his the evolution of the mind. Chittka and Wilson met puters, or the universe have anything when they were both fellows of the Berlin Institute students, Martin Lindauer, peered into of the sort? If so, we are at risk of ex- of Advanced Study, and their discussions laid the a beehive and discovered that some panding the definition of conscious- foundations for the thoughts presented here. This bees continued these discussions into ness to include ever more living and article is an adaptation of an essay previously pub- the night. Before midnight, they “talk- nonliving beings until the term be- lished in Aeon, aeon.co. Email: TK ed about” locations visited the previ- comes meaningless. 364 American Scientist, Volume 107 Helga Heilmann The construction of honeycombs by Apis mellifera requires the coordinated and cooperative were the opposite of those it expected. activities of many dozens of individuals. Workers manufacture and manipulate wax into a Deprived of its ability to anticipate highly regular hexagonal pattern. In the process, they evaluate the space available and the cur- what it should see as a result of its own rent state of construction, and incorporate a diversity of communication signals from others. intentions, the fly behaved erratically. These rich instinctual repertoires had been thought to come at the expense of learning capac- Insects, with their heads in the normal ity; however, very few behavioral routines are fully hardwired, and even comb construction position, appear to have another of the skills have to be partially learned by honeybees. key ingredients of consciousness: the ability to predict what will happen in Solid proof of consciousness in any- actions, so that they can distinguish the future as a result of self-generated one except oneself is of course unat- sensory changes caused by their movements, which allows them to tainable. Everyone else may be a ma- movements from changes caused by move and act effectively. chine or a zombie. But then—say some external forces. Under normal condi- At its evolutionary roots, we believe philosophers—we may be brains in tions, animals expect the environment that consciousness is an adaptation vats, as in the movie The Matrix. to move in a predictable manner when that helped to solve the problem of One elementary phenomenon at the they turn their heads voluntarily. This how moving organisms can extract heart of biological consciousness is expectation allows them to anticipate meaningful information from their self-recognition: the ability to recognize what will happen next, as a result of sense organs. In an ever-changing and oneself as distinct from another entity, their own actions or intentions. only semi-predictable environment, as well as to plan, pay attention, recall Early versions of efference copies consciousness can solve this problem memories of specific events, and take were proposed in the 19th century, more efficiently than unconscious the perspective of another creature. If although the term was first coined mechanisms possibly could. As the the image on your retina suddenly tilts by the German biologists Erich von late zoologist Donald Griffin wrote in by 45 degrees, you know that this is Holst and Horst Mittelstaedt in their his book Animal Minds (1992), “Envi- fine if it’s the result of deliberately in- study of flies. In one of their experi- ronmental conditions vary so much clining your head—If not, you may be ments in 1950, they inverted the in- that for an animal’s brain to have pro- witnessing a major seismic event, and put to the fly’s brain from the left and grammed specifications for optimal you had better run. right eyes using a rather crude (and behavior in all situations would re- Animals are thought to tell the dif- cruel) technique: The thin neck of the quire an impossibly lengthy instruc- ference between these scenarios via fly was twisted by 180 degrees, and its tion book.” what’s known as an efference copy: an head then glued in place upside down. Bees provide further evidence that internal signal that communicates the The result was that, when the animal insects can cope with unusual chal- consequences of the animal’s own turned left or right, the sensory signals lenges that no instruction book will an- www.americanscientist.org 2019 November–December 365 zone and foreseen a suboptimal result before it occurred. On another occasion, Huber’s team created an environment where the bees had no choice but to build their hive on a glass surface. The research- ers observed that one of several combs broke off the ceiling of a hive during winter. Hive construction normally pauses during the winter months when the bees minimize their activity to ensure that their stores lasts until spring.