Comparing Lives: Rush Rhees on Humans and Animals

In several posthumously published writings about the differences between humans and animals, Rush Rhees criticises the view that human lives are more important than (or superior to) animal lives. Rhees' views may seem to be in sympathy with more recent critiques of “speciesism.” However, the most commonly discussed anti‐speciesist moral frameworks – which take the capacity of sentience as the criterion of moral considerability – are inadequate. Rhees' remark that both humans and animals can be loved points towards a different way of accounting for the moral considerability of humans and animals that avoid the problems of the capacity‐based approaches.     

Attribute centrality and imaginative thought

Participants' representations of the concept human were examined to differentiate three types of associations between concepts and their component attributes: the capacity of concepts to cue attributes (attribute accessibility), the capacity of attributes to cue concepts (instance accessibility), and the extent to which attributes are thought of as central to concepts (attribute centrality). The findings provide information about the concept human itself and, more generally, about the functionally distinct roles those different attribute-concept associations play in guiding imaginative thought. College students listed attributes that differentiate humans from other animals, rated the centrality of those attributes, and listed animals that possess those attributes. Other students drew and described extraterrestrials that possessed some of the attributes that were found to vary across those listing and rating tasks. Rated centrality was the most important determinant of an attribute's impact on imaginative generation. When the imagined extraterrestrials were supposed to possess attributes that had been rated as central to humans (intelligence, emotional complexity, or opposable thumbs), participants projected more aspects of human form onto them than when the creatures were supposed to possess less central attributes or when attributes were unspecified.     

语法的进化连续性及进化起源解释

语法是人类交流系统有别于其他动物的关键特征之一。行为比较研究表明, 除人类外的其他灵长目动物也能理解并掌握抽象的顺序排序规则; 神经生物学比较研究表明, 支持排序处理的神经机制来自人类与其他灵长目动物共同具有的脑区。因此语法所依赖的序列学习能力在人类与其他灵长目动物间具有进化连续性。词汇限制假说、事件感知假说与自我驯化假说分别从不同角度对人类语法的进化起源进行了解释。未来研究需要探讨人工语法任务中所发现的脑神经机制是否是层级结构加工的通用处理器, 并进一步澄清语义加工与语法加工的关系。     

What bats have to say about speech and language

Understanding the biological foundations of language is vital to gaining insight into how the capacity for language may have evolved in humans. Animal models can be exploited to learn about the biological underpinnings of shared human traits, and although no other animals display speech or language, a range of behaviors found throughout the animal kingdom are relevant to speech and spoken language. To date, such investigations have been dominated by studies of our closest primate relatives searching for shared traits, or more distantly related species that are sophisticated vocal communicators, like songbirds. Herein I make the case for turning our attention to the Chiropterans, to shed new light on the biological encoding and evolution of human language-relevant traits. Bats employ complex vocalizations to facilitate navigation as well as social interactions, and are exquisitely tuned to acoustic information. Furthermore, bats display behaviors such as vocal learning and vocal turn-taking that are directly pertinent for human spoken language. Emerging technologies are now allowing the study of bat vocal communication, from the behavioral to the neurobiological and molecular level. Although it is clear that no single animal model can reflect the complexity of human language, by comparing such findings across diverse species we can identify the shared biological mechanisms likely to have influenced the evolution of human language.     

Listening to language at birth: evidence for a bias for speech in neonates

The nature and origin of the human capacity for acquiring language is not yet fully understood. Here we uncover early roots of this capacity by demonstrating that humans are born with a preference for listening to speech. Human neonates adjusted their high amplitude sucking to preferentially listen to speech, compared with complex non-speech analogues that controlled for critical spectral and temporal parameters of speech. These results support the hypothesis that human infants begin language acquisition with a bias for listening to speech. The implications of these results for language and communication development are discussed. For a commentary on this article see Rosen and Iverson (2007).     

Evolution of the brain and intelligence

Intelligence has evolved many times independently among vertebrates. Primates, elephants and cetaceans are assumed to be more intelligent than 'lower' mammals, the great apes and humans more than monkeys, and humans more than the great apes. Brain properties assumed to be relevant for intelligence are the (absolute or relative) size of the brain, cortex, prefrontal cortex and degree of encephalization. However, factors that correlate better with intelligence are the number of cortical neurons and conduction velocity, as the basis for information-processing capacity. Humans have more cortical neurons than other mammals, although only marginally more than whales and elephants. The outstanding intelligence of humans appears to result from a combination and enhancement of properties found in non-human primates, such as theory of mind, imitation and language, rather than from 'unique' properties.     

The nature of the language faculty and its implications for evolution of language (Reply to Fitch, Hauser, and Chomsky)

In a continuation of the conversation with Fitch, Chomsky, and Hauser on the evolution of language, we examine their defense of the claim that the uniquely human, language-specific part of the language faculty (the “narrow language faculty”) consists only of recursion, and that this part cannot be considered an adaptation to communication. We argue that their characterization of the narrow language faculty is problematic for many reasons, including its dichotomization of cognitive capacities into those that are utterly unique and those that are identical to nonlinguistic or nonhuman capacities, omitting capacities that may have been substantially modified during human evolution. We also question their dichotomy of the current utility versus original function of a trait, which omits traits that are adaptations for current use, and their dichotomy of humans and animals, which conflates similarity due to common function and similarity due to inheritance from a recent common ancestor. We show that recursion, though absent from other animals' communications systems, is found in visual cognition, hence cannot be the sole evolutionary development that granted language to humans. Finally, we note that despite Fitch et al.'s denial, their view of language evolution is tied to Chomsky's conception of language itself, which identifies combinatorial productivity with a core of “narrow syntax.” An alternative conception, in which combinatoriality is spread across words and constructions, has both empirical advantages and greater evolutionary plausibility.     

Use of experimenter-given cues in dogs

Since the observations of O. Pfungst the use of human-provided cues by animals has been well-known in the behavioural sciences (“Clever Hans effect”). It has recently been shown that rhesus monkeys (Macaca mulatta) are unable to use the direction of gazing by the experimenter as a cue for finding food, although after some training they learned to respond to pointing by hand. Direction of gaze is used by chimpanzees, however. Dogs (Canis familiaris) are believed to be sensitive to human gestural communication but their ability has never been formally tested. In three experiments we examined whether dogs can respond to cues given by humans. We found that dogs are able to utilize pointing, bowing, nodding, head-turning and glancing gestures of humans as cues for finding hidden food. Dogs were also able to generalize from one person (owner) to another familiar person (experimenter) in using the same gestures as cues. Baseline trials were run to test the possibility that odour cues alone could be responsible for the dogs’ performance. During training individual performance showed limited variability, probably because some dogs already “knew” some of the cues from their earlier experiences with humans. We suggest that the phenomenon of dogs responding to cues given by humans is better analysed as a case of interspecific communication than in terms of discrimination learning. Received: 30 May 1998 / Accepted after revision: 6 September 1998     

语言如何进化

人类语言具有复杂多变的递归结构,漫长的物种进化过程中唯独人类精通语言。语言的进化始于大约两百万年前的“更新世时期”,语言在当时作为一种认知适应对于人类应对自然界带给人类的挑战（如动物掠食与森林毁坏）有很大帮助。人类进化过程中学习与文化因素形成一种选择压力促使人际交流语法化,人际交流语法化引发大脑容量增加,然而,最初的语言进化与基因无关。学习与文化压力也使交流的媒介依次变为手语模式、表情模式与语言模式。交流媒介的逐渐变化最终导致了FOXP2基因突变,FOXP2基因突变让智人具有了自主的言语能力。与地球上其它的人科动物相比,人类的语言能力使人类在进化中具有明显的优势     

The search for phonology in other species

Human language draws on a complex set of cognitive, motor and auditory skills. Some of these are found in other species but others are thought to be absent. There has been a burst of research in this area over the past five years, both in examining natural communication systems and also in the laboratory, exposing animals to human language. Most of the work has focused on analogies to syntax. Although many of the fundamental building blocks for basic phonological skills might be found outside humans, most aspects of core phonology have never been investigated.     

`Babbling' and social context in infant monkeys: parallels to human infants

Although only humans use spoken language, the vocal communication of many animals shares some features with language. Within the context of their family, normal children and young non-human primates develop proficiency in the nuances of their species-specific vocal communication system. Engaging in speech-like phonetic activity, or babbling, occurs in all normal children regardless of their native language. Similar periods of vocal development have not been described previously for non-human primates. However, in the pygmy marmoset, a South American monkey, we found that the primary vocal behavior of infants parallels many characteristics of human infant babbling. These analogous features include universality, repetition, use of a subset of the adult vocal repertoire, recognizably adult-like vocal structure and lack of a clear vocal referent. Also, like human infants, young marmosets develop in a closely knit family unit that includes both parents and often older siblings. In this context, the babbling-like behavior of the marmoset infant stimulates interaction with caregivers, thereby serving a key role in the infant's own development. These developmental and social processes indicate that the study of vocal development in non-human primate species can provide insights into the function of babbling in humans.     

Antarctic skuas recognize individual humans

Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans.     

Directedness and engagement in chimpanzee vocal ontogeny

Directedness and engagement during pre-verbal vocal communication play a major role in language development. What was their role in the evolution of language? This question invites us to examine these behaviours in chimpanzee vocal ontogeny. We collected observational data on infant (N = 15) and juvenile (N = 13) chimpanzees at Chimfunshi Wildlife Orphanage, Zambia. We examined the impact of age and vocalization type (grunts, whimpers, laughs and screams) on directed cues (gaze directedness and face directedness) and engagement (mutual face directedness) during vocal communication. We also assessed the impact of directed cues and engagement on social interactions by coding the behaviour of social partners before, during and after a vocalisation, and examining whether they contingently changed their behaviour in response to the vocalisation if it was directed or if engagement occurred. We found that face directed vocalisations showed a general increase during ontogeny and we observed call-type dependent effects of age for mutual face directedness. Only face directed vocalisations were significantly predictive of behavioural responses in social partners. We conclude that like young humans, young chimpanzees routinely exhibit directed behaviours and engagement during vocal communication. This social competency improves during ontogeny and benefits individuals by increasing the chances of eliciting behavioural responses from social partners. Directedness and engagement likely provide a foundation for language phylogenetically, as well as ontogenetically.

Research Highlights

• We show that directedness and engagement routinely occur during early chimpanzee vocalisations.
• Directedness increases throughout chimpanzee vocal ontogeny, similar to human infants.
• Directedness enhances social partner responsiveness, demonstrating a direct benefit to this style of communication.
• Directedness and engagement could provide a route towards language phylogenetically as well as ontogenetically.

     

Sexual Difference,Animal Difference: Derrida and Difference “Worthy of Its Name”

I challenge the age‐old binary opposition between human and animal, not as philosophers sometimes do by claiming that humans are also animals, or that animals are capable of suffering or intelligence, but rather by questioning the very category of “the animal” itself. This category groups a nearly infinite variety of living beings into one concept measured in terms of humans—animals are those creatures that are not human. In addition, I argue that the binary opposition between human and animal is intimately linked to the binary opposition between man and woman. Furthermore, I suggest that thinking through animal differences or differences among various living creatures opens up the possibility of thinking beyond the dualist notion of sexual difference and enables thinking toward a multiplicity of sexual differences.     

Alleged problems in attributing beliefs,and intentionality,to animals

The ordinary attribution of intentionality to (nonhuman) animals raises serious problems for fashionable linguistic accounts of belief and of intentionality generally; and many of the alleged problems arise from such linguistic theories of mind. Another deeper source of alleged problems is the apartness thesis, that there is a significant difference in kind, with substantial moral import, between humans and other animals; for the last lines of defence of this erroneous thesis consist in making out that there are significant intentional differences. A wide range of recent arguments against assigning intentionality (in the full sense) to animals are criticized in detail: those of Stich and Williams, in terms of animals lacking effective or specifiable concepts (concepts now replacing souls); those of Stich and Davidson based on the requirement for beliefs of an isomorphic belief network; those based on the usual opacity of intentionality; those of Descartes and Davidson and others based on the requirement of, or arguments to the essentiality of, language use for attributions of intentionality; arguments based on the requirement of capacity for pretence or awareness of error; and arguments used by Vendler and Malcolm. Several different arguments for assigning intentionality to animals are then advanced, arguments from cerebral organization, exteriorization arguments, and interiorization arguments from the semantical analysis of intentionality. The main arguments advanced are not analogical; they are not anthropocentric, or the result of personifying languageless animals; and the attributions of intentionality they lead to are not impoverished or of reduced status.     

THE IMAGO DEI AS THE MIND OF JESUS CHRIST

In this essay I examine David Clough's interpretation of the imago Dei and his use of “creaturely” language in his book On Animals: Volume 1, Systematic Theology. Contrary to Clough, I argue that the imago Dei should be interpreted as being uniquely human. Using a neuroscientific approach, I elaborate on my claim that while Jesus is the image of God perfected, the imago Dei is best understood as having the mind of Christ. In regards to language, I make the case that using terms such as “creature” when referring to nonhuman animals is problematic in that it can serve to alienate human beings from their capacity to image God. In addition I argue that “creaturely” language raises concerns for the African American community given Western Christianity's history as it relates to their valuation of black bodies and human enslavement.     

Wittgenstein and the Animal Origins of Linguistic Communication

Wittgenstein's notorious sample of a ‘complete primitive language’ (viz. the builders’ game of the Philosophical Investigations) is often thought to be closer in kind to animal forms of communication than human language. Indeed, it has been criticised on precisely these grounds. But such debates make little sense if we take seriously Wittgenstein's idea that language is a family resemblance concept. So, rather than argue that the builders’ game ‘really is a language’ (or not), I propose to turn the debate on its head and welcome the comparison. By changing our perspective in this way, I suggest that we can see that the learning of language is crucially dependent on forms of communication that are animal in nature. I then discuss how these lessons might shed light on empirical research into both the ontogenetic and phylogenetic origins of linguistic communication.     

Domestic horses send signals to humans when they face with an unsolvable task

Some domestic animals are thought to be skilled at social communication with humans due to the process of domestication. Horses, being in close relationship with humans, similar to dogs, might be skilled at communication with humans. Previous studies have indicated that they are sensitive to bodily signals and the attentional state of humans; however, there are few studies that investigate communication with humans and responses to the knowledge state of humans. Our first question was whether and how horses send signals to their potentially helpful but ignorant caretakers in a problem-solving situation where a food item was hidden in a bucket that was accessible only to the caretakers. We then examined whether horses alter their behaviours on the basis of the caretakers’ knowledge of where the food was hidden. We found that horses communicated to their caretakers using visual and tactile signals. The signalling behaviour of the horses significantly increased in conditions where the caretakers had not seen the hiding of the food. These results suggest that horses alter their communicative behaviour towards humans in accordance with humans’ knowledge state.