Advanced Review Cognitive ethology Carolyn A. Ristau∗ Cognitive Ethology, the field initiated by Donald R Griffin, was defined by him as the study of the mental experiences of animals as they behave in their natural environment in the course of their normal lives. It encompasses both the problems defined by Chalmers as the ‘hard’ problem of consciousness, phenomenological experience, and the ‘easy’ problems, the phenomena that appear to be explicable (someday) in terms of computational or neural mechanisms. Sources for evidence of consciousness and other mental experiences that Griffin suggested and are updated here include (1) possible neural correlates of consciousness, (2) versatility in meeting novel challenges, and (3) animal communication which he saw as a potential ‘window’ into their mental experiences. Also included is a very brief discussion of pertinent philosophical and conceptual issues; cross-species neural substrates underlying selected cognitive abilities; memory capacities especially as related to remembering the past and planning for the future; problem solving, tool use and strategic behavioral sequences such as those needed in anti-predator behaviors. The capacity for mirror self-recognition is examined as a means to investigate higher levels of consciousness. The evolutionary basis for morality is discussed. Throughout are noted the admonitions of von Uexkull¨ to the scientist to attempt to understand the Umwelt of each animal. The evolutionary and ecological impacts and constraints on animal capacity and behavior are examined as possible. © 2013 John Wiley & Sons, Ltd. How to cite this article: WIREs Cogn Sci 2013, 4:493–509. doi: 10.1002/wcs.1239 INTRODUCTION they behave in their natural environments in the course of their normal lives. The mental experiences included, hatisitliketobeabat?’... the title of 1 among others, awareness, purposes, consciousness, ‘Wa philosophical essay by Nagel. He argued and general and specific cognitive capacities. that we could never know what such an experience His endeavor provoked considerable contro- was like, for as human beings/scientists, we have no versy. But as Griffin had earlier remarked in 1958, way of determining or understanding the nature of concerning biologists’ great reluctance to consider any bat mind state. In correspondence with Nagel the possibility of animals’ use of sonar for echolo- 2,3 and in his writings, Donald R. Griffin the founder cation (now well established), ‘Excessive caution can of ‘Cognitive Ethology’ argued otherwise... that it sometimes lead one as far astray as rash enthusiasm.’4 was indeed possible to make at least a start into He proposed exploring several lines of evidence such investigations, and even, assuming evolutionary for this new field: (1) possible neural correlates of continuity of mental experience, to imagine some consciousness; (2) versatility of organisms in adapting of the experiences of other organisms. Cognitive to new challenges for which they have not been Ethology was to be a beginning scientific exploration either genetically prepared or had pertinent learning of the mental experiences of animals, particularly as experiences; (3) communication by animals, that can be interpreted as reporting subjective experiences. ∗Correspondence to: [email protected] Findings have potential impacts on human Department of Psychology, Barnard College of Columbia behavior. We are more likely to be concerned about University, New York, NY, USA animal’s well being and conservation of their habitat Conflict of interest: The author has declared no conflicts of interest if we understand them to be conscious, intelligent for this article. beings. Volume 4, September/October 2013 © 2013 John Wiley & Sons, Ltd. 493 Advanced Review wires.wiley.com/cogsci A BRIEF FORAY INTO PHILOSOPHICAL including perspective taking, empathy, and generally ISSUES CONCERNING COGNITIVE the ability to model another’s mental and physical 16–18 ETHOLOGY perspective). Awareness and Consciousness The problems Griffin raises about consciousness are Approaches to the Study of Animal what the philosopher Chalmers,5 in a seminal paper, Capacities has termed the (phenomenal) ‘hard’ problems and the A significant contribution to the study of animals is the ‘easy’ problems. The latter, in Chalmers’ view, are concept von Uexkull¨ 19 proposed in 1909, that of the those in which, using methods of cognitive science, ‘Umwelt,’ meaning the environment as an organism the phenomena appear to be explicable (someday) in perceives it and interacts with it. Several organisms terms of computational or neural mechanisms. The can appear to live in the ‘same’ environment, but ‘easy’ problems entail cognitive abilities including in effect those environments are vastly different, discriminating, integrating information, deliberately with each organism sensing and emphasizing different controlling behavior, and accessing and reporting aspects, interacting differently, using the environment mental states among others. (It should be noted differently. that many scientists would consider that such ‘easy’ Another approach to species comparisons is problems require more than a neural/computational a ‘functional’ one. Thus ethologists describe and approach, a very reductionistic type of explanation.) compare foraging strategies, food preparation/storage, The ‘hard’ problems are the phenomenological ones, territory selection/defence, selection/creation of a the very experience of a mental state, a perception, home, mate selection, parenting behavior and the a pain, ‘what it is like to be xxx.’ In the past, concomitant cognitive skills required in each. We most scientists have avoided the ‘hard’ problems. have learned that cognitive abilities in one sphere Many philosophers, however, including Aristotle,6 need not generalize to another. Such modularity raises Descartes,7 and contemporary philosophers of the issue of ‘what’ has evolved?What circuitry? Are mind8–11 have been concerned with issues of animal there ‘core knowledge systems’ common to humans consciousness and reason. The philosopher Searle12,13 and some other species20–22 or can abilities in one is probably most closely aligned with the stances of sphere generalize to another(s)... over the eons or Griffin, and considers that a main issue is not whether possibly in an organism over a lifetime? We do find nonhuman animals are conscious, but which animals many examples of one available biological ‘solution’ are conscious and to what level of consciousness. being used over evolution for other purposes.23 Even Darwin entitled a book ‘The Expression of Truly appropriate comparisons of abilities the Emotions in Man and Animals.’14 As Griffin notes, across species likewise entails understanding the Darwin’s inclusion of mental continuity in evolution developmental and learning processes involved: does is far more reasonable a scientific approach than the capacity occur full-blown in all species members? beginning with the denial of such capacity. Griffin What experiences/learning trials were required; how further suggests that a yet more conservative, neutral many; over how long a time? approach would be to assume p = 0.5 with respect to Work with captive species has revealed abilities the probability of consciousness in animals and then possibly latent in the natural environment. In a few to increase or decrease that probability as data are instances, captive great apes have been observed to accumulated.15 actively teach as distinguished from exhibiting a Nevertheless, despite confusion over definitions, behavior which may be copied. For example, the more (not all) contemporary animal behavior sci- signing chimpanzee (Pan troglodytes) Washoe actively entists appear to grant, to at least some species, molded the hands of young chimpanzee Loulis into phenomenological ‘awareness’ or ‘primary conscious- the sign for food, a training technique often used ness,’ if not the higher levels of consciousness. Those by humans with Washoe.24 Some captive apes, in higher levels are often termed ‘sentience,’ described particular, young apes, achieve abilities not observed as the depth of awareness of self and others. Sen- in the field, e.g. spontaneous pointing, and do so more tience includes self-awareness (both self as a body readily if they have more (positive) interactions with entailing self-recognition and self including a men- humans.25 Even monkeys can be specifically taught tal entity existing in a continual fashion in the to point and then they generalize to use the skill in a past, present, and future), metacognition (the abil- communicative manner in varied circumstances.17 ity to think about the contents of one’s own mental We need to recognize that some observed states/feelings), and Theory of Mind (various abilities behaviors may be ‘default,’ those exhibited in urgent 494 © 2013 John Wiley & Sons, Ltd. Volume 4, September/October 2013 WIREs Cognitive Science Cognitive ethology circumstances or in the presence of very potent stimuli, Brain Structures Underlying Cognitive and can be detrimental in that particular situation. In Capacities less constrained circumstances, the organism may have Despite current disagreements about directly linking reacted differently. For example, the beavers’ cognitive specific neural activity or areas with consciousness, abilities utilized in dam construction and repair certain brain structures have been shown to play sig- have been denigrated, because some experimental nificant roles in both humans and other species,