Primate vocal communication is very different from human language. Differences are most pronounced in call production. Differences in production have been overemphasized, however, and distracted attention from the information that primates acquire when they hear vocalizations. In perception and cognition, continuities with language are more apparent. We suggest that natural selection has favored nonhuman primates who, upon hearing vocalizations, form mental representations of other individuals, their relationships, and their motives. This social knowledge constitutes a discrete, combinatorial system (...) that shares several features with language. It is probably a general primate characteristic whose appearance pre-dates the evolution of spoken language in our hominid ancestors. The prior evolution of social cognition created individuals who were preadapted to develop language. Several features thought to be unique to language—like discrete combinatorics and the encoding of propositional information—were not introduced by language. They arose, instead, because understanding social life and predicting others’ behavior requires a particular style of thinking. (shrink)

Many researchers consider language to be definitionally unique to humans. However, increasing evidence suggests that language emerged via a series of adaptations to neural systems supporting earlier capacities for visuomotor integration and manual action. This paper reviews comparative neuroscience evidence for the evolutionary progression of these adaptations. An outstanding question is how to mechanistically explain the emergence of new capacities from pre-existing circuitry. One possibility is that human brains may have undergone selection for greater plasticity, reducing the extent to (...) which brain organization is hard-wired and increasing the extent to which it is shaped by socially transmitted, learned behaviors. Mutations that made these new abilities easier or faster to learn would have undergone positive selection, and over time, the neural changes once associated with individual neural plasticity would tend to become heritable, innate, and fixed. Clearly, though, language is not entirely “innate;” it does not emerge without the requisite environmental input and experience. Thus, a mechanistic explanation for the evolution of language must address the inherent trade-off between the evolutionary pressure for underlying neural systems to be flexible and sensitive to environmental input vs. the tendency over time for continually adaptive behaviors to become reliably expressed in an early-emerging, canalized, less flexible manner. (shrink)

Following the publication of the Weatherall report on the use of non-human primates in research, this paper reflects on how to provide appropriate and ethical models for research beneficial to humankind. Two of the main justifications for the use of non-human primates in biomedical research are analysed. These are the “least-harm/greatest-good” argument and the “capacity” argument. This paper argues that these are equally applicable when considering whether humans are appropriate subjects of biomedical research.

The use of non-human primates in biomedical research is a contentious issue that raises serious ethical and practical concerns. In the European UnionEuropean Union, where regulations on their use are very tight, the number of non-human primates used in research has been in decline over the past decade. However, this decline has been paralleled by an increase in numbers used elsewhere in the world, with less regard for some of the ethical issues. There is evidence that (...) researchers from high-income countries, where regulations on the use of non-human primates are strict, may be tempted to conduct some of their experiments in countries where regulation is less strict, through new collaborative efforts. In collaborative ventures, equivalence in the application of ethical standardsEthical standards in animal research, regardless of location, is necessary to avoid this exploitationExploitation. (shrink)

The evolution from pre-human primates to modern Homo sapiens is a complex one involving many domains, ranging from the material to the social to the cognitive, both at the individual and the community levels. This article focuses on a critical qualitative transition that took place during this evolution involving both the social and the cognitive domains. For the social domain, the transition is from the face-to-face forms of social interaction and organization that characterize the non-human primates (...) that reached, with Pan, a hiatus due to the centripetal effects that highly individualized behavior has on a social system. The transition is to the relation-based forms of social organization that evolved in the hominins ancestral to Homo sapiens and are universal in human societies today. For the cognitive domain, this transition involves going from behavior responding mainly to phenomenal level sensory inputs to behavior formed in accordance with the concept of a relation, initially abstracted from behavior patterns, then extending the concept of a relation beyond abstraction from behavior patterns to the concept of a relation generated recursively through constructing the relation of a relation. This extension made possible the construction of systems of relations; initially genealogical systems of relations constructed culturally using the logic of recursion, and subsequently, the symbolic, computational systems of kin term relations referred to by anthropologists as kinship terminologies. The latter are “constructed realities” in the sense this term is used by cultural anthropologists. It follows that the evolution of relation-based systems of social interaction is not adequately accounted for through population model evolutionary accounts such as the Dual Inheritance Theory of human evolution since “constructed realities” constitute collectively and publicly shared cultural knowledge rather than the individually and privately possessed knowledge that is assumed in the population model framework for human evolution. (shrink)

The use of non-human primates in biomedical research is a contentious issue that raises serious ethical and practical concerns. In the European Union, where regulations on their use are very tight, the number of non-human primates used in research has been in decline over the past decade. However, this decline has been paralleled by an increase in numbers used elsewhere in the world, with less regard for some of the ethical issues (e.g. genetic manipulations). There is (...) evidence that researchers from high-income countries (HICs), where regulations on the use of non-human primates are strict, may be tempted to conduct some of their experiments in countries where regulation is less strict, through new collaborative efforts. In collaborative ventures, equivalence in the application of ethical standards in animal research, regardless of location, is necessary to avoid this exploitation. (shrink)

The field of language evolution has recently made Gricean pragmatics central to its task, particularly within comparative studies between human and non-human primate communication. The standard model of Gricean communication requires a set of complex cognitive abilities, such as belief attribution and understanding nested higher-order mental states. On this model, non-human primate communication is then of a radically different kind to ours. Moreover, the cognitive demands in the standard view are also too high for human infants, (...) who nevertheless do engage in communication. In this paper I critically assess the standard view and contrast it with an alternative, minimal model of Gricean communication recently advanced by Richard Moore. I then raise two objections to the minimal model. The upshot is that this model is conceptually unstable and fails to constitute a suitable alternative as a middle ground between full-fledged human communication and simpler forms of non-human animal communication. (shrink)

Emerging biotechnology may soon allow the creation of genetically human organs inside animals, with non-human primates and pigs being the best candidate species. This prospect raises the question of whether creating organs in primates in order to then transplant them into humans would be more acceptable than using them for research. In this paper, we examine the validity of the purported moral distinction between primates and other animals, and analyze the ethical acceptability of using (...) class='Hi'>primates to create organs for human use. (shrink)

This paper proposes an intermediate account of personhood, based on the capacity to participate in intersubjective interactions. We articulate our proposal as a reply to liberal and restrictive accounts, taking Mark Rowlands’ and Stephen Darwall’s proposals as contemporary representatives of each view, respectively. We argue that both accounts fall short of dealing with borderline cases and defend our intermediate view: The criteria of personhood based on the second-person perspective of mental state attribution. According to it, a person should be able (...) to participate in intersubjective interactions. We apply our proposal to the borderline cases of non-human primates and human infants. (shrink)

Given Heyes's construal of there is still no convincing evidence of theory of mind in human primates, much less nonhuman. Rather than making unfounded assumptions about what underlies human social competence, one should ask what mechanisms other primates have and then inquire whether more sophisticated elaborations of those might not account for much of human competence.

Both genetic and environmental factors have key roles in determining aggressive tendencies. In particular, reaction to stress appears to be an important factor in precipitating aggressive episodes and individuals may vary in their ability to cope with stressful environments depending on their genetic make up. Evidence from humans and primates indicates that adverse rearing conditions may interact with variants in stress and neurotransmitter pathway genes leading to antisocial and/or violent behaviour. Common alleles of some serotonin pathway genes, including those (...) involved in its degradation (monoamine oxidase A, MAOA), or its re‐uptake into pre‐synaptic neurones (serotonin transporter, SERT) have been shown to confer functional variation. Examination of the interaction between the alleles of such polymorphisms (in particular those affecting MAOA) and environmental stressors suggest that they may provide protection against, or increase sensitivity to, abusive upbringing; an observation that may explain part of the variability in developmental outcomes associated with maltreatment. BioEssays 29: 227–236, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

In recent years, the biological inheritance of what has been traditionally known as original sin has come more clearly to the fore. Examining the genetic forebears of Homo sapiens has allowed for a richer understanding of what exactly the "propagation" of original sin might really mean. The wounded imperfection of the human biological inheritance has clarified matters concerning the question of where exactly original sin comes from. Since the human experience of sentience and agency is built biologically upon (...) the shoulders of its ancestors, the human experience of being always-already bound by sin—an essential component of the meaning of original sin—comes into clearer relief. At the same time, a much richer... (shrink)

The Weatherall report on the use of non-human primates in research was published in 2006. Its main conclusion was that there is a strong scientific case for the use of non-human primates in some cases, but the report stressed the importance of evaluating each case in the light of the availability of alternatives. In addition to arguing for the scientific necessity of using non-human primates in research, the report also provided an ethical justification. As (...) could be expected, the report was harshly criticised by animal rights groups, but in the academic literature, only two critical replies appeared. In what follows, I will describe the ethical justification for non-human primate research as it is laid out in the Weatherall report and then consider the criticism in the academic literature. I conclude that the report’s ethical justification for the use of non-human primates in research, in particular in basic neuroscientific research, has not been convincingly challenged by its critics. Since the criticism of the report is limited and represents only a small part of the academic discussion about the use of non-human primates in research, and a still smaller part of the ethical discussion about animal research, it is important that the discussion continue both at the academic and social level. (shrink)

How do human children come up to carve up and think of the world around them in its most general and abstract structure? And to which degree are these general forms of viewing the world shared by other animals, notably by non-human primates? In response to these questions of what could be called comparative metaphysics, this paper discusses new evidence from developmental and comparative research to argue for the following picture: human children and non-human (...) class='Hi'>primates share a basic framework of natural ontology: they think about their natural surroundings in essentialist ways in terms of natural kind objects constituted by their essential properties, and in generic terms as governed by general descriptive regularities. In contrast, there is a great divide when it comes to how human children and non-human primates carve up their social environment: only human children then go on to use their essentialist and generic thinking for developing a distinctively social ontology, to conceive of their surrounding in terms of socially constituted objects governed by general prescriptive norms. (shrink)

One of the themes that has been widely addressed in both the implicit learning and statistical learning literatures is that of rule learning. While it is widely agreed that the extraction of regularities from the environment is a fundamental facet of cognition, there is still debate about the nature of rule learning. Rey and colleagues show that the comparison between human and non‐human primates can contribute important insights to this debate.

Communication, when defined as an act intended to affect the psychological state of another individual, demands the use of inference. Either the signaler, the recipient, or both must make leaps of understanding which surpass the semantic information available and draw from pragmatic clues to fully imbue and interpret meaning. While research into human communication and the evolution of language has long been comfortable with mentalistic interpretations of communicative exchanges, including rich attributions of mental state, research into animal communication has (...) balked at theoretical models which describe mentalized cognitive mechanisms. We submit a new theoretical perspective on animal communication: the model of inferential communication. For use when existing proximate models of animal communication are not sufficient to fully explain the complex, flexible, and intentional communication documented in certain species, specifically non-human primates, we present our model as a bridge between shallower, less cognitive descriptions of communicative behavior and the perhaps otherwise inaccessible mentalistic interpretations of communication found in theoretical considerations of human language. Inferential communication is a framework that builds on existing evidence of referentiality, intentionality, and social inference in primates. It allows that they might be capable of applying social inferences to a communicative setting, which could explain some of the cognitive processes that enable the complexity and flexibility of primate communication systems. While historical models of animal communication focus on the means-ends process of behavior and apparent cognitive outcomes, inferential communication invites consideration of the mentalistic processes that must underlie those outcomes. We propose a mentalized approach to questions, investigations, and interpretations of non-human primate communication. We include an overview of both ultimate and proximate models of animal communication, which contextualize the role and utility of our inferential communication model, and provide a detailed breakdown of the possible levels of cognitive complexity which could be investigated using this framework. Finally, we present some possible applications of inferential communication in the field of non-human primate communication and highlight the role it could play in advancing progress toward an increasingly precise understanding of the cognitive capabilities of our closest living relatives. (shrink)

The current view that behaviour which is manifest in non-human primates forms a baseline for human behaviours is examined with special reference to the development of gender determination. A review of 21 non-human primate societies suggests that the behaviour of the sexes relates to assumption and occupation of societal roles defined by the local group. The significance of these findings for the human condition is discussed.

This paper provides a theoretical exploration of how comparative research on the expression of emotions has traditionally focused on the visual mode and argues that, given the neurophysiological, developmental, and behavioral evidence that links touch with social interactions, focusing on touch can become an ideal mode to understand the communication of emotions in human and nonhuman primates. This evidence shows that touch is intrinsically linked with social cognition because it motivates human and nonhuman animals from birth to (...) form social bonds. It will be shown that touch is one of the modes of interaction used by the mother-infant or caregiver- infant dyad that facilitates the expression of emotions by the infant (and later the expression of emotions by the adult that the infant has become) in ways that are understood by other members of the group. (shrink)

The scientific, ethical, and policy issues raised by research involving the engraftment of human neural stem cells into the brains of nonhuman primates are explored by an interdisciplinary working group in this Policy Forum. The authors consider the possibility that this research might alter the cognitive capacities of recipient great apes and monkeys, with potential significance for their moral status.

Non-human animal models of human diseases advance our knowledge of the genetic underpinnings of disease and lead to the development of novel therapies for humans. While mice are the most common model organisms, their usefulness is limited. Larger animals may provide more accurate and valuable disease models, but it has, until recently, been challenging to create large animal disease models. Genome editors, such as Clustered Randomised Interspersed Palindromic Repeat, meet some of these challenges and bring routine genome engineering (...) of larger animals and non-human primates well within reach. There is growing interest in creating NHP models of brain disorders such as autism, depression and Alzheimer’s, which are very difficult to model or study in other organisms, including humans. New treatments are desperately needed for this set of disorders. This paper is novel in asking: Insofar as NHPs are being considered for use as model organisms for brain disorders, can this be done ethically? The paper concludes that it cannot. Notwithstanding ongoing debate about NHPs’ moral status, animal welfare concerns, the availability of alternative methods of studying brain disorders and unmet expectations of benefit justify a stop on the creation of NHP model organisms to study brain disorders. The lure of using new genetic technologies combined with the promise of novel therapeutics presents a formidable challenge to those who call for slow, careful, and only necessary research involving NHPs. But researchers should not create macaques with social deficits or capuchin monkeys with memory deficits just because they can. (shrink)

The Weatherall Report claims that research on non-human primates is permitted and morally required. The argument rests on the following thought experiment: > The hospital fire : A hospital is on fire. Some of the residents are humans and others are non-human animals. You can only save one group. What do you do? Some people have the intuition that we should rescue the humans. According to the report, if we accept that human lives have priority over (...) non-human lives in this case, consistency requires us to support the use of non-human animals in research. This is because both cases are about saving human lives at the expense of the lives of non-human animals. Two critical replies appeared in the literature, by E J Moore1 and Muireann Quigley.2 In a recent paper3 Gardar Arnason claims that such objections fail. I will argue, however, that his assessment is unconvincing. The first objection pressed by Moore is that there are fundamental disanalogies between The hospital fire and biomedical research. In that scenario we face a life-or-death emergency situation whereas in biomedical research we do not. In such situations it may be justified to prioritise those closest to us (eg, species …. (shrink)

What is the relation between philosophical theorizing and experimental data? A modest set of naturalistic assumptions leads to what I term the force-field puzzle. The assumption that philosophy is continuous with natural science, as captured in Quine’s force-field metaphor, seems to push us simultaneously towards thinking that there have to be conceptual constraints upon how we interpret experimental data and towards thinking that there cannot be such conceptual constraints, because all theorizing must be accountable to data and observation. The key (...) to resolving the force-field puzzle is to take a more nuanced view of how conceptual constraints can be accountable to data and observation. This can be done by developing conceptual arguments in conjunction with interpretative frameworks for making sense of experimental evidence. This paper shows how attending to important differences between different types of mindreading yields tools for interpreting experimental and observational data in a manner consistent with a (conceptually derived) constraint that I have developed elsewhere. This is the first-order constraint that second-order thinking, or thinking about thinking, is only available to language-using creatures. (shrink)

Can Boyer's model of ownership psychology provide useful insights for comparative research? I apply his model to argue that we currently have evidence for possession psychology (based on competitive resource acquisition) in non-human primates, but not for ownership psychology.

Extracting the regularities of our environment is one of our core cognitive abilities. To study the fine-grained dynamics of the extraction of embedded regularities, a method combining the advantages of the artificial language paradigm and the serial response time task was used with a group of Guinea baboons in a new automatic experimental device. After a series of random trials, monkeys were exposed to language-like patterns. We found that the extraction of embedded patterns positioned at the end of larger patterns (...) was faster than the extraction of initial embedded patterns. This result suggests that there is a learning advantage for the final element of a sequence that benefits from the contextual information provided by previous elements. (shrink)

Three- to six-year-olds were given Heyes's proposed task and theory of mind tasks. Although they correlated, Heyes's was harder; only 50% of participants with a theory of mind reached a criterion of 75% correct. Because of the complex series of inferences involved in Heyes's task, it is possible that one could have a theory of mind and fail Heyes's version.

The cortical representation of concepts varies according to the information critical for their development. Living categories, being mainly based upon visual information, are bilaterally represented in the rostral parts of the ventral stream of visual processing; whereas tools, being mainly based upon action data, are unilaterally represented in a left-sided fronto-parietal network. The unilateral representation of tools results from involvement in actions of the right side of the body.

A variety of studies show that parental absence early in life leads to deleterious effects on the developing CNS. This is thought to be largely because evolutionary-dependent stimuli are necessary for the appropriate postnatal development of the young brain, an effect sometimes termed the “experience-expectant brain,” with parents providing the necessary input for normative synaptic connections to develop and appropriate neuronal survival to occur. Principal among CNS systems affected by parental input are the monoamine systems. In the present study,N= 434 (...) rhesus monkeys (233 males, 201 females) were reared in one of two conditions: as mother-reared controls (MR;n= 269) or without adults with 24-h access to same-aged peers (PR;n= 165). When subjects were six-months-old, they underwent a separation paradigm involving 4, sequential, four-day social separations from their mothers or peers, with each separation followed by three-day reunions with their mothers or their peers. Prior to the separation paradigm, baseline cisternal CSF samples were obtained, as well as at the end of each the four social separations, and after final separation, during a recovery period. CSF was assayed for concentrations of monoamine metabolites and a blood sample was genotyped for the serotonin transporter (5-HTT) genotype. Replicating earlier landmark findings, PR subjects with thesallele exhibited lower baseline concentrations of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), when compared to PR subjects homozygous for theLallele. MR subjects were undifferentiated by genotype. PR subjects exhibited lower CSF 5-HIAA concentrations during baseline, but higher CSF 5-HIAA during social separations, when compared to MR subjects. There were rearing effects for the dopamine metabolite homovanillic acid (HVA) and for the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG), with PR subjects showing higher HVA and lower MHPG when compared to MR subjects. These findings indicate that there are long-term deficits in the response of monoamines following early maternal absence. The results of this study confirm and extend earlier findings that early parental absence has deleterious consequences for the development of the monoamine systems, and that these consequences are modulated by the 5-HTT genotype. (shrink)

“The Ethics of Infection Challenges in Primates,” by Anne Barnhill, Steven Joffe, and Franklin Miller, is an exceptionally timely contribution to the literature on animal research ethics. Animal research has long been both a source of high hopes and a cause for moral concern. When it comes to infection challenge studies with nonhuman primates, neither the hope—to save thousands of human lives from such diseases as Ebola and Marburg—nor the concern—the conviction that primates deserve especially strong (...) protections—could be much higher. Coming just a few years after the National Institutes of Health adopted the Institute of Medicine's recommendations regarding chimpanzees, Barnhill and colleagues attempt to nudge the clarification and specification—one might say the evolution—of NHP research ethics and regulation. They assert that NHP challenge studies “are not justified by marginal gains in human safety or by efficacy gains that are unlikely to translate directly into saving human lives or preventing morbidity.” How, in turn, is their standard—which, although stringent, does permit causing NHPs to suffer and die for human benefit—to be justified? (shrink)

I review recent work from armchair and cross-cultural epistemology on whether humans possess a knowledge concept as part of a universal “folk epistemology.” The work from armchair epistemology fails because it mischaracterizes ordinary knowledge judgments. The work from cross-cultural epistemology provides some defeasible evidence for a universal folk epistemology. I argue that recent findings from comparative psychology establish that humans possess a species-typical knowledge concept. More specifically, recent work shows that knowledge attributions are a central part of primate social cognition, (...) used to predict others’ behavior and guide decision-making. The core primate knowledge concept is that of truth detection (across different sensory modalities) and retention (through memory) and may also include rudimentary forms of indirect truth discovery through inference. In virtue of their evolutionary heritage, humans inherited the primate social-cognitive system and thus share this core knowledge concept. (shrink)