My position is simply stated. Animal research ethics should take the question of the decisional authority of other intensely social cognitive animals very seriously. But for a few exceptions I will introduce later, we should not include, or continue to use, an intensely social cognitive animal who expresses sustained dissent in the course of research (Fenton 2014).
Three terms require a brief explanation (I will leave “dissent” until later). An individual has decisional authority over a course of action just in case their decision on the matter holds or is respected. Cognitive animals possess various capacities to acquire and store information about themselves or their environment, use it to order their future behavior, and correct it in light of negative feedback arising from its use (Allen and Bekoff 1997; Fenton 2012a; Gould 2004). Intensely social animals require a stable social environment in order to develop typically and are vulnerable to the development of behavioral disorders when it is not (Bloomsmith et al. 2006).
Various behavioral and cognitive studies of other intensely social cognitive animals, from chimpanzees to rats, are revealing preferences of treatment expressed inside and outside of laboratory settings (e.g., Bloomsmith et al. 2006; Olsson and Westlund 2007). Dissent can signal such preferences. I am very aware of the dangers of anthropomorphism lurking in the background of talk about animal preferences, but I do not think I am guilty of this error of ascription. Several empirical claims, useful for defending my position, are not in serious doubt within the relevant behavioral and cognitive sciences. First, sociality did not first emerge with the appearance of our species, or even earlier hominins. Second, we are not the first animals to have developed various perceptual, affective (e.g., emotional) and cognitive capacities with which to engage our physical and social worlds. Third, it is not even the case that, among social cognitive animals, plastic social hierarchies first emerged with our species (De Waal and Tyack 2003). Taken together, these widely accepted empirical claims should soften resistance to the view that other intensely social cognitive animals form preferences of treatment. What may clinch it are the lengths taken by some animals to secure better treatment from conspecifics (or even heterospecifics like us), the frustration sometimes expressed if they fail, and retaliations when attacked or unsupported by allies during conflict (e.g., Thierry 2011; de Waal 1998).
One species that will come up in this chapter and make these claims more concrete is the chimpanzee. This is not because these animals are one of the few where we can find some or most of the capacities and behavior I have introduced above. I could have focused on canids like wolves (Cordoni and Palagi 2008), Cetacea like dolphins (Connor 2007), or corvids like ravens (Braun and Bugnyar 2012), but my work to date has focused on chimpanzees, and so again here (see Fenton 2012b, 2014). In what follows, I will both situate and defend my position (I also discuss some of these ideas in Fenton and Shriver, forthcoming).
The timeliness of re-envisioning the role of other animals’ agential capacities when deciding to use them in research is captured in several observations about emergent attitudes or practices in laboratories (or captive settings explicitly created to study other animals) and the continuing strength of some philosophical criticisms of the status quo in animal research. As I briefly present them, it should become clear that they call out for a repositioning of animal research ethics in a way that better (and more strongly) resembles what has become standard fare in human bioethics.
“Good science is humane science” is a sentiment that resonates through much of the literature touching on the “3 R’s,”1 laboratory enrichment, and animal research ethics (e.g., Orlans 2002; Poole 1997). Admittedly, this can confuse largely descriptive with normative claims about animal research – after all, good science need not be humane science – but there are strong correlations between stressed animal subjects and confounders that undermine the clarity, quality, or reliability of experimental data (Coleman 2010). Though the elimination of stressors in the environment can help alleviate confounders, two other efforts are often recommended: (a) enriching the captive conditions in which animal research subjects live, and (b) where possible, training the subjects through positive reinforcement (henceforth, PRT) to cooperate during routine husbandry, research, or veterinary procedures (Bloomsmith et al. 2006).
Both (a) and (b) are relevant to situating my position. Where intensely social cognitive animal research subjects are group housed (a form of social enrichment), a social hierarchy emerges that facilitates the satisfaction of, as well as reflects, preferences of treatment (not unlike what we observe in free-living counterparts). These expressed preferences of treatment remind us that how these other animals are treated matters to them, a point that we will return to later. The importance of PRT for my purposes lies in the effort to secure the cooperation of animal research subjects. Such training not only reduces the stress of the research animals, it also reduces the stress of those handling them, and permits a respectful treatment that can better cohere with the concern that many laboratory personnel have for the research subjects in their care (Coleman 2010). PRT encourages the animal research subjects to build expectations about daily procedures and imminent events (e.g., a blood draw or moving to another cage) and allows the possibility of cooperation, or refusal to cooperate, in contexts where the animals have some understanding of what is about to happen (Walker 2006). This point will be useful when we discuss consent.
Adding to these developments, some conscientious animal researchers have drawn attention to the ethical space in which they use other animals in research (and the moral commitments they make in using them). They emphasize that their research subjects are beings who are due respect and will sometimes express this in terms of valuing their subjects’ cooperation (e.g., see Berns et al. 2012). Matsuzawa writes:
The chimpanzees in the KUPRI [Kyoto University Primate Research Institute] laboratory are free: it is completely up to each subject whether he or she will come to the booth to participate in a cognitive task or not. If they prefer not to participate, they may stay outside. It must be noted that choosing to participate in an experiment does not affect the total amount of food given to a chimpanzee per day…. Suppose that a chimpanzee does decide to come to the booth. Again, it is up to them whether to start the first trial of the test session or not…. This means that nothing happens before the subject touches the key [on the monitor] of his or her own will…. [T]he response-contingent delivery of the food has a special value for the chimpanzee. Based on their free will, they work on a cognitively challenging task and as a result they are rewarded.
(Matsuzawa 2006: 20)
Such emergent practices or changing attitudes in laboratory (or captive) contexts demonstrate that the cooperation of other animals is enjoying greater significance to some of those working in animal research. As I shift to more theoretical considerations, the need to re-envision the moral weight of this cooperation, and by implication lack of cooperation, will take on considerable force.
Typically, one of two background value systems frame the use of other animals in research: (1) anthropocentric speciesism, and (2) human exceptionalism. Either value system permits the use of other animals in research that is prohibited on (at least some) humans. Though some may view (1) and (2) as different terms for the same thing, they can be distinguished. Anthropocentric speciesism is the differential moral regard of individuals on no other grounds than that they belong, or do not belong, to the species Homo sapiens. Human exceptionalism, on the other hand, concedes that not all humans (or their interests) will enjoy moral preeminence over all other animals (or their interests). For human exceptionalism, it is enough that some (perhaps many) humans (or their interests) will consistently enjoy it (Dunayer 2013). An example of this position is privileging the interests of persons over the interests of nonpersons, at least as long as personhood is restricted to Homines sapientes. Such a use of personhood typically includes human juveniles and adults and, more controversially, infants.
Two examples where one or the other of these value systems is probably at work may be illustrative. Consider toxicological research. Toxicology research involves both the study of typically functioning cells, tissues, and biological processes, and what happens when they are exposed to various chemical agents at different dose levels. To get a sufficient understanding of the potential toxicity of an agent, it is often important to see how it is absorbed and distributed within a complex living system (e.g., a mouse or rat) (Society of Toxicology 2006). Such in vivo research can cause physical damage, considerable pain, and even death. The use of other animals is supposed to reduce such risks to humans (Beauchamp et al. 2008; Rowan 2011). Though pharmaceutical phase 1 trials provide an example of using humans to test product safety, dominant ethical frameworks restrict intentionally harming or endangering research subjects to nonhumans. This effectively implies differential moral treatment based on species identity and so reflects anthropocentric speciesism. Human exceptionalism is more readily seen in differential ethical constraints as we cross from human to nonhuman biomedical or behavioral research. As I will discuss in a little more detail below, it is now standard to seek the consent of research subjects, or their surrogates, in research using humans. It is widely held to be immoral to fail to do so. The fundamental basis of this constraint is a respect for persons (Meslin and Dickens 2008). To date, this constraint is widely absent in nonhuman animal research. This is particularly evident when the nonhuman animals who fail to cooperate during routine or research-related laboratory procedures are physically restrained or immobilized. Though I have previously noted that an increasing number of researchers reject these practices, they are commonly regarded as ethically justified (Carbone 2004).
There is an extensive literature critical of anthropocentric speciesism with no need to rehearse it in detail here. One of the more illuminating moves is DeGrazia’s argument involving other, now extinct, hominins (DeGrazia 2007). Making some slight adjustments to his argument, suppose for the moment that Homo sapiens is not the only extant species of our genus. Imagine, rather, that members of the species Homo neanderthalensis and Homo floresiensis still walk the Earth. How should we regard their interests in, say, liberty or freedom from intentional harm (assuming, not unreasonably, that they have them)? Could we imagine that our own interests in expanding our biological knowledge or product safety rightly trump them? For DeGrazia, it would be arbitrary to think that our interest in expanding our knowledge enjoys a higher moral status than a Homo floresiensis’ interest to not be intentionally harmed, when we would not similarly intentionally harm a fellow Homo sapiens. After all, what could possibly be the difference that would justify such an ethical stance? Restating their respective species’ identities is not an adequate answer to that question (it merely restates the point at issue). To make any progress here, we must turn our gaze to the presence or absence of capacities enjoying moral significance (e.g., capacities to suffer, enter into reciprocal relationships, or form preferences of treatment). Once this is recognized, it challenges credibility to think that there are moral significant capacities possessed by every Homo sapiens that are absent in every Homo floresiensis and justify the differential moral regard in dispute. This “capacities turn” is the keystone to rejecting anthropocentric speciesism, and of course quickly moves us beyond our genus or even tribe (Hominini) (DeGrazia 2007).
The second value system – human exceptionalism – is much more entrenched and more difficult to abandon. As I mentioned earlier, a standard ground for the differential moral treatment of, and regard for, humans and nonhuman animals is the personhood of the relevant humans (along with restricting the notion of “person” to some or many members of our species). On the face of it, human exceptionalism appears to lack the arbitrariness of anthropocentric speciesism. After all, on a common construal of the term, “person” picks out individuals with particular capacities rather than simply all members of the taxon Homo sapiens. Though the exact number is in dispute, these capacities often include emotionality, linguistic or communicative capacity, rationality, self-awareness, and sentience (Warren 2014; see also DeGrazia 2007). Arbitrariness is often revealed, however, when the conditions of, or candidates for, personhood are interrogated. Consider that much effort can be spent protecting under-developed humans (think of late-term fetuses or newborns) while avoiding comparable efforts on behalf of other animals. Where these humans do not possess interests or vulnerabilities relevantly different from those of at least some other animals, the arbitrariness is revealed. The recurrent use of arguments concerning so-called marginal others (e.g., fetuses, infants, or neurologically atypical humans), despite understandable criticisms about their implicit ableism (e.g., Kittay 2009), are best understood as a response to human exceptionalism. If some humans were not placed at the “center” of the moral universe (where their interests enjoy preeminence over the interests of all others), there would be no margins to concern us. Those politically opposed to the use of arguments concerning so-called marginal others would do well to oppose human exceptionalism (some similar points are made in Donaldson and Kymlicka, Forthcoming). Arguably, their reasonable concerns about our social views of (and duties to) the differently abled – particularly those who do not qualify as persons in any straightforward (non-arbitrary) way – provides a powerful reason for doing so.
Though I am not alone in my wariness of the use of personhood in applied ethics (Beauchamp 1999), its pervasive presence might incline some to regard my stance as absurd, or at least implausible. After all, ethicists associate appeals to personhood with core commitments in human research ethics: respect for autonomy and preferences of treatment as well as obligations not to treat subjects merely as means to the ends of greater scientific or biomedical knowledge (Luna and Macklin 2009). As these commitments are not under serious dispute, it might appear as if personhood should not be either. Two considerations should cause pause here: (1) the lack of decisive conditions of personhood, and (2) the lack of progress in certain areas of bioethics because of intractable disputes over the nature and scope of personhood. As I have already mentioned, it is something of a received tradition to restrict the ascription of personhood to individuals possessing a to-be-specified number of psychological or behavioral capacities (see those listed above). This tradition faces challenges from those who do not share its conviction about the favored capacities or their relevance (think of those who would defend the personhood – and not just the potential personhood – of properly developing human fetuses). Philosophers can be quick to talk of different senses of “personhood” to try and protect the traditional (metaphysical) use of the term – perhaps fetal advocates are using a legal sense of personhood, which makes an individual visible to law as a possessor of certain rights or obligations, or a moral sense that simply picks out individuals who should enjoy certain strong protections from harm or exploitation (for an example of this breakdown, see Kind 2015). But dissenters are not obviously doing anything untoward if they refuse to re-see their view of personhood as different from, or used in a different sense than, the one favored by such philosophers. Even if their position is underpinned by an appeal to a conception of the human soul or to the belief that humans are created in the image of divinity – appeals commonly rejected in at least contemporary analytic philosophy – their position does not then become obviously wrong. Where, in moments of non-sectarian reflection, we can concede this legitimate plurality of views of personhood, we can see that it can do little to resolve issues surrounding our treatment of other animals. What’s more, as we can now readily observe stalemates in bioethical disputes at the beginning or end of human lives (e.g., the permissibility of human embryonic experimentation/enhancement or our obligations to individuals with advanced dementia), we should be reticent to appeal to personhood in animal research ethics. There is little reason (except, perhaps, species prejudice) to think such appeals will be any more decisive when the focus is a chimpanzee or domestic dog rather than a human (Fenton 2012b).
Where, then, have my comments or contentions taken us? With the collapse of anthropocentric speciesism and strong reasons to reject human exceptionalism, we must face the following possibility: if another animal, say a chimpanzee, dissents from participation in a harmful study – imagine that she refuses to extend her arm for a blood draw or present her body for a biopsy – this may be sufficient reason to exclude her from the study. Without an appeal to anthropocentric speciesism or human exceptionalism ready at hand, this chimpanzee’s preference of treatment would appear to enjoy relevantly similar moral weight to a relevantly similar preference of treatment expressed by a member of our own species. Diekema and Wendler have independently defended the view that sustained dissent, even of very young children, in a research setting is a good prima facie reason to exclude them from the relevant study (Diekema 2006; Wendler 2006). Though I will have more to say about their positon in the next section, such a progressive stance could be extended to other animals and, in a framework devoid of anthropocentric speciesism and strong human exceptionalism, probably should be. Alternatively, if we are to weight a chimpanzee’s preferences differently than we would a young child expressing sustained dissent, we will need something other than anthropocentric speciesism or human exceptionalism to justify it, and I know of no alternatives.
As I am committed to avoiding anthropomorphic errors in talking of the agential capacities of other animals, I now need to say more about how my sense of dissent can be applied to other animals. I also need to say more about repositioning animal research ethics in a way that better (and more strongly) resembles what has become standard fare in human bioethics. It is to these two concerns that I now turn, though in reverse order.
The decisional authority of research subjects is not in doubt when they are competent humans. Since the emergence of the Nuremberg Code in the aftermath of the Second World War, the consent of competent human research subjects has enjoyed ever increasing prominence in research ethics (see The Belmont Report or the latest version of the Declaration of Helsinki). Such research atrocities as the Tuskegee Syphilis Studies have served to underline its significance, even though the Willowbrook Hepatitis Studies remind us that consent is not a panacea to protect vulnerable human subjects from exploitation and harm (Diekema 2006; Luna and Macklin 2009). The importance of consent lies in respecting the decisional authority of human agents. A number of normative ethical theories, be they utilitarian, deontological, or virtue theories, can justify this respectful treatment, so its importance is over-determined in applied ethics. What is interesting for my purposes is that some progressive bioethics has taken a turn to consider the decisional authority of non-competent human agents such as children.
Talk of competence, at least as it is used in contemporary bioethics, is a way of acknowledging the decisional authority of typically functioning, autonomous agents (the exemplar is a typically functioning, autonomous human adult) to make decisions that (positively or negatively) impinge upon their well-being or welfare. Respecting this authority in research settings requires providing these agents with information needed to make an informed decision relative to their values or preferences (Beauchamp and Childress 2012). Children, particularly under the age of 14, are customarily held to be incompetent. But this does not preclude them from decisions to participate in research. Seeking assent from juvenile humans is taken to be required where it is an expression of respect for the kind of being they are (Diekema 2006). Typically, assent requires that the relevant children understand something of the nature of the research (and that it is research, not therapy) as well as the risks involved. It will also require their express willingness to participate (Diekema 2006). Such understanding is beyond the ken of some very young children (or children who can neither consent nor assent), but, as I mentioned earlier, progressive bioethics does not preclude them from decisions to participate in research. Where a procedure or research setting is distressing to a very young child (or a child who can neither consent nor assent), and they express “sustained dissent” (Wendler 2006: 233), they should be precluded from participating – or so some have powerfully argued (see Diekema 2006; Wendler 2006).
I agree with this progressive bioethics but do not think that some of these commitments concern only humans (Fenton 2014). Instead, I take the view that both an understanding of consent and dissent is relevant to animal research ethics. We have already seen why the preferences of treatment of other intensely social cognitive animals should not be ignored. I have also noted the rising use of PRT to secure the cooperation of cognitive research subjects in routine husbandry, research, or veterinary procedures. PRT connects quite quickly to consent, when seen in a certain way. During PRT, animals learn to associate certain cues with the imminent occurrence of what, without the relevant training, can be a (significant) stressor (think of the presentation of a needle or even the appearance of a particular laboratory technician who regularly takes blood samples or genital swabs) (Laule et al. 2003). It can reasonably be said that, over time, these cognitive animals come to understand something of what is about to transpire, and this understanding offers them a to-be-specified degree of resilience against stress. What’s more, their continued cooperative behavior despite the relevant cues can be reasonably interpreted as consent to the imminent procedure (for some similar points, see Walker 2006). Though such consent is not consent to research (as the relevant cognitive animals cannot think in terms of research versus, say, therapy), it can qualify as consent to procedures.
Dissent, in contrast to either consent or assent, does not require a deep understanding of stressors or the imminent occurrence of stressors. After all, this is how it can be used in progressive pediatric research ethics to deal with young children. In my previous work, I have suggested three conditions for dissent capacity that fall out of its use in that area of human research ethics: a dissenter must have a “capacity (1) for distress, pain, or stress; (2) to anticipate the future occurrence of distress, pain, or stress; and (3) to ‘ask’ that it stop or to express that the relevant distress, pain, or stress is unwanted” (Fenton 2014: 134). For young children, this can be expressed in their inconsolable distress when presented with relevant stimuli, their refusal to extend their arm or turn their head, or their refusal to sit still (Diekema 2006).
Typically functioning chimpanzees are examples of nonhuman animals who possess these capacities of dissent. Conditions (1) and (2) are acknowledged in the scientific literature that advocates training chimpanzees to cooperate when presented with stressors or where they discuss the use of analgesics, anesthesia, anxiolytics, and tranquilizer darts (e.g., Laule et al. 2003; Lopresti-Goodman et al. 2015). Condition (3) is in evidence where control of uncooperative chimpanzees is achieved through the use of immobilizing devices, such as squeeze cages or even restraints (e.g., Perlman et al. 2012). Among non-laboratory chimpanzees, aggression, retaliations, and tantrums have been connected with anger at being socially snubbed, unsupported by allies at times when they are under threat from conspecifics, or frustrated after failing to manipulate the behavior of a conspecific (e.g., de Waal 1998). In each of these cases, preferences of treatment can play a crucial role in explaining the relevant chimpanzee’s behavior. That such animals can form preferences of treatment connects us again with condition (3) above.
To summarize, PRT can be understood as a way of seeking an animal research subject’s consent to research procedures. The sustained dissent of chimpanzee research subjects – expressed, say, in an unwillingness to present their arm or hindquarters or move into an adjacent cage – should be respected, all things being equal. To do anything less is to introduce a differential regard for the decisional authority of research subjects that, to remain consistent, threatens advances in progressive pediatric research ethics.
The central implication of my position seems clear: chimpanzees (and other intensely social cognitive animals with dissent capacity) should not be forced to participate in research. Their dissent should be respected, all other things being equal. But why use the phrase “all other things being equal”? Discussions in pediatric research ethics have highlighted two areas where the research can at least sometimes proceed even when the child is not cooperating or actively resisting participation: (1) where the research offers some to-be-specified hope of therapeutic benefit (that cannot be obtained outside of a research setting), and (2) where the research promises to yield substantial knowledge relevant to the (typically, patient) population of which the child is a part. Risk to child subjects is an important restriction on pediatric research and, with regards to (2), permits their inclusion where the risks only slightly exceed what is regarded as minimal. This appeal to minimal risk will take into account the harm from ignoring their distress, and so cannot serve to override their sustained distress if we have good reason to think that they will be significantly harmed by our doing so (Diekema 2006; Wendler 2006). This, then, can be extended to research involving other intensely social cognitive animals. Where research either promises therapeutic benefit or substantial knowledge relevant to a population of which a chimpanzee is a part, we might be able to proceed with research even in the face of dissent (for similar points, see DeGrazia 2007). The relevant sense of minimal risk would need to be specified, but it could be captured by risks ordinarily faced by chimpanzees either in captive settings, where they are respectfully treated, or where, in free-living populations, they are not facing anthropogenic risks to life or limb (Ferdowsian and Fuentes 2014). This sense of minimal risk approximates a sense prevalent in US pediatric research ethics. There, something presents minimal risk
where the probability and magnitude of harm or discomfort anticipated in the proposed research are not greater, in and of themselves, than those ordinarily encountered in daily life or during the performance of routine physical or psychological examinations or tests.
(Diekema 2006: S7)
There is another implication of my approach. We cannot commit to respecting the dissent capacity of other intensely social cognitive animals if we place them in circumstances or settings that serve to erode or destroy that capacity or preclude its acquisition. This will constrain how these animals are raised, housed, and treated in research settings. It is common knowledge that some laboratory environments have had catastrophic impact on the psychological well-being of captive chimpanzees (see Brüne et al 2006). Where this impact negatively affects a chimpanzee’s ability to deal with future stressors, including interactions with laboratory technicians or conspecifics (perhaps they become overly aggressive at the presentation of a needle or in response to a conflict with a conspecific in group housing), or where this impact adversely affects their ability or willingness to express dissent (e.g., they express a learned helplessness), they should be removed from, or excluded from participation in, research. Their future inclusion in research should be predicated on their ability to dissent (or to express uncooperative behavior) in a way that is not indicative of a behavioral problem. Where the research might itself impact their capacity to dissent, it is ethically out of bounds.
I have both explained and defended my view that intensely social cognitive animals should not be forced to participate in research. When, say, a chimpanzee refuses to cooperate with researchers or attending personnel, their sustained refusal should be respected – all other things being equal. If their sustained dissent threatens their place in a study, and cannot be overcome with non-coercive measures (e.g., rewards), the chimpanzee should be excluded from the research – again, all other things being equal. What’s more, the research setting in which intensely social cognitive animal research subjects are housed and used should not destroy or preclude the acquisition of their dissent capacity. Where it has, they should be removed from the relevant studies until they recover. If there are research settings that inevitably destroy or preclude the acquisition of such an animal’s dissent capacity, they are ethically proscribed.
1 The 3 R’s are refinement, reduction, and replacement. Together, they are supposed to work to reduce the distress, pain, or stress of animals used in science. Refinement prescribes the reduction or elimination of scientifically unnecessary pain or suffering (distress). Reduction prescribes the use of the least number of animals that are scientifically necessary to conduct a study. Replacement prescribes the use of less sentient animals or non-animal systems where the use of more sentient animals is scientifically unnecessary (Flecknell 2002).
L. Carbone, What Animals Want: Expertise and Advocacy in Laboratory Animal Welfare Policy (New York: Oxford University Press, 2004). D. DeGrazia, “Human-Animal Chimeras: Human Dignity, Moral Status, and Species Prejudice,” Metaphilosophy 38(2–3) (2007): 309–29. A. Fenton, “Can a Chimp Say “No”? Reenvisioning Chimpanzee Dissent in Harmful Research,” Cambridge Quarterly of Healthcare Ethics 23 (2014): 130–9. H. Ferdowsian and A. Fuentes, “Harms and Deprivation of Benefits for Nonhuman Primates in Research,” Theoretical Medicine and Bioethics 35 (2014): 143–56. H. Kantin and D. Wendler, “Is There a Role for Assent and Dissent in Animal Research?” Cambridge Quarterly of Healthcare Ethics 24(4) (2015): 459–72. R. Walker, “Human and Animal Subjects of Research: The Moral Significance of Respect Versus Welfare,” Theoretical Medicine and Bioethics 27 (2006): 305–31.
Allen, C., and Bekoff, M. (1997) Species of Mind: The Philosophy and Biology of Cognitive Ethology, Cambridge, MA: The MIT Press.
Beauchamp, T. L. (1999) “The Failure of Theories of Personhood,” Kennedy Institute of Ethics Journal 9(4): 309–24.
Beauchamp, T. L., and Childress, J. F. (2012) Principles of Biomedical Ethics, Seventh Edition, New York: Oxford University Press.
Beauchamp, T. L., Orlans, F. B., Dresser, R., Morton, D. B., and Gluck, J. P. (2008) The Human Use of Animals: Case Studies in Ethical Choice, Second Edition, New York: Oxford University Press.
Berns, G. S., Brooks, A. M., and Spivak, M. (2012) “Functional MRI in Awake Unrestrained Dogs,” PloS One 7(5): 1–7.
Bloomsmith, M. A., Schapiro, S. J., and Strobert, E. A. (2006) “Preparing Chimpanzees for Laboratory Research,” ILAR Journal 47(4): 316–25.
Braun, A., and Bugnyar, T. (2012) “Social Bonds and Rank Acquisition in Raven Nonbreeder Aggregations,” Animal Behaviour 84: 1507–15.
Brüne, M., Brüne-Cohrs, U., McGrew, W., and Preuschoft, S. (2006) “Psychopathology in Great Apes: Concepts, Treatment Options and Possible Homologies to Human Psychiatric Disorders,” Neuroscience and Biobehavioral Reviews 30: 1246–59.
Carbone, L. (2004) What Animals Want: Expertise and Advocacy in Laboratory Animal Welfare Policy, New York: Oxford University Press.
Coleman, K. (2010) “Caring for Nonhuman Primates in Biomedical Research Facilities: Scientific, Moral and Emotional Considerations,” American Journal of Primatology 71: 1–6.
Connor, R. C. (2007) “Dolphin Social Intelligence: Complex Alliance Relationships in Bottlenose Dolphins and a Consideration of Selective Environments for Extreme Brain Size Evolution in Mammals,” Philosophical Transactions of the Royal Society B 362: 587–602.
Cordoni, G., and Palagi, E. (2008) “Reconciliation in Wolves (Canis lupus): New Evidence for a Comparative Perspective,” Ethology 114: 298–308.
DeGrazia, D. (2007) “Human-Animal Chimeras: Human Dignity, Moral Status, and Species Prejudice,” Metaphilosophy 38(2–3): 309–29.
de Waal, F. B. M. (1998) Chimpanzee Politics: Power and Sex Among Apes, Revised Edition, Baltimore, MD: The Johns Hopkins University Press.
de Waal, F. B. M., and Tyack, P. L. (2003) Animal Social Complexity: Intelligence, Culture, and Individualized Societies, Cambridge, MA: Harvard University Press.
Diekema, D. S. (2006) “Conducting Ethical Research in Pediatrics: A Brief Historical Overview and Review of Pediatric Regulations,” The Journal of Pediatrics 149: S3–S11.
Donaldson, S., and Kymlicka, W. (Forthcoming) “Rethinking Membership and Participation in an Inclusive Democracy: Cognitive Disability, Children, and Animals,” in B. Arneil and N. Hirschmann (eds.) Disability and Political Theory, New York: Cambridge University Press.
Dunayer, J. (2013) “The Rights of Sentient Beings: Moving Beyond Old and New Speciesism,” in R. Corbey and A. Lanjouw (eds.) The Politics of Species: Reshaping Our Relationships with Other Animals, New York: Cambridge University Press, pp. 27–39.
Fenton, A. (2012a) “Neuroscience and the Problem of Other Animal Minds: Why It May Not Matter So Much for Neuroethics,” The Monist 95(3): 463–85.
——— (2012b) “On the Need to Redress an Inadequacy in Animal Welfare Science: Toward an Internally Coherent Framework,” Biology and Philosophy 27: 73–93.
——— (2014) “Can a Chimp Say “No”? Reenvisioning Chimpanzee Dissent in Harmful Research,” Cambridge Quarterly of Healthcare Ethics 23: 130–39.
Fenton, A., and Shriver, A. (forthcoming) “Animal Minds: The Neuroethics of Nonhuman Dissent,” in L. Syd, M. Johnson, and Karen S. Rommelfanger (eds.) Routledge Handbook of Neuroethics, New York: Routledge.
Ferdowsian, H., and Fuentes, A. (2014) “Harms and Deprivation of Benefits for Nonhuman Primates in Research,” Theoretical Medicine and Bioethics 35: 143–56.
Flecknell, P. (2002) “Replacement, Reduction and Refinement,” ALTEX 19: 73–8.
Gould, J. L. (2004) “Animal Cognition,” Current Biology 14(10): R372–75.
Kind, A. (2015) Persons and Personal Identity, Cambridge: Polity.
Kittay, E. F. (2009) “Ideal Theory Bioethics and the Exclusion of People With Severe Cognitive Disabilities,” in H. Lindemann, M. Verkerk, and M. U. Walker (eds.) Naturalized Bioethics: Toward Responsible Knowing and Practice, New York: Cambridge University Press, pp. 218–37.
Laule, G. E., Bloomsmith, M. A., and Schapiro, S. J. (2003) “The Use of Positive Reinforcement Training Techniques to Enhance the Care, Management, and Welfare of Primates in the Laboratory,” Journal of Applied Animal Welfare Science 6(3): 163–73.
Lopresti-Goodman, S. M., Bezner, J., and Ritter, C. (2015) “Psychological Distress in Chimpanzees Rescued From Laboratories,” Journal of Trauma and Dissociation 16: 349–66.
Luna, F., and Macklin, R. (2009) “Research Involving Human Beings,” in H. Kuhse and P. Singer (eds.) A Companion to Bioethics, Second Edition, Malden, MA: Wiley Blackwell, pp. 457–68.
Matsuzawa, T. (2006) “Sociocognitive Development in Chimpanzees: A Synthesis of Laboratory Work and Fieldwork,” in T. Matsuzawa, M. Tomonaga, and M. Tanaka (eds.) Cognitive Development in Chimpanzees, Tokyo: Springer-Verlag Tokyo, pp. 3–33.
Meslin, E. M., and Dickens, B. M. (2008) “Research Ethics,” in P. A. Singer and A. M. Viens (eds.) The Cambridge Textbook of Bioethics, New York: Cambridge University Press, pp. 187–93.
Olsson, I. A. S., and Westlund, K. (2007) “More Than Numbers Matter: The Effect of Social Factors on Behaviour and Welfare of Laboratory Rodents and Non-Human Primates,” Applied Animal Behaviour Science 103: 229–54.
Orlans, F. B. (2002) “Ethical Themes of National Regulations Governing Animal Experiments: An International Perspective,” in J. P. Gluck, T. DiPasquale, and F. B. Orlans (eds.) Applied Ethics in Animal Research: Philosophy, Regulation, and Laboratory Applications, West Lafayette: Purdue University Press, pp. 131–47.
Perlman, J. E., Bloomsmith, M. A., Whittaker, M. A., McMillan, J. L., Minier, D. E., and McCowan, B. (2012) “Implementing Positive Reinforcement Animal Training Programs at Primate Laboratories,” Applied Animal Behaviour Science 137: 114–26.
Poole, T. (1997) “Happy Animals Make Good Science,” Laboratory Animals 31: 116–24.
Rowan, A. N. (2011) “The Use of Animals in Toxicological Research,” in T. L. Beauchamp and R. G. Frey (eds.) The Oxford Handbook of Animal Ethics, New York: Oxford University Press, pp. 906–18.
Society of Toxicology (2006) “Animals in Research: The Importance of Animals in the Science of Toxicology,” www.toxicology.org/pubs/docs/air/AIR_Final.pdf, accessed September 3rd, 2016.
Thierry, B. (2011) “The Macaques: A Double-Layered Social Organization,” in C. J. Campbell, A. Fuentes, K. C. MacKinnon, S. K. Bearder, and R. M. Stumpf (eds.) Primates in Perspective, Second Edition, New York: Oxford University Press, pp. 229–41.
Walker, R. (2006) “Human and Animal Subjects of Research: The Moral Significance of Respect Versus Welfare,” Theoretical Medicine and Bioethics 27: 305–31.
Warren, M. A. (2014) “On the Moral and Legal Status of Abortion,” in H. LaFollette (ed.) Ethics in Practice: An Anthology, Fourth Edition, Malden, MA: Wiley Blackwell, pp. 132–40.
Wendler, D. S. (2006) “Assent in Pediatric Research: Theoretical and Practical Considerations,” Journal of Medical Ethics 32: 229–34.