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.     

Five-month-old infants know humans are solid, like inanimate objects

Infants know that humans are exempt from some of the principles that govern the motion of inanimate objects: for instance, humans can be caused to move without being struck. In the current study, we report that infants nevertheless do apply some of the same principles to both humans and objects, where appropriate. Five-month-old infants expect humans, like all material objects, to be solid.     

On behalf of moderate speciesism

ABSTRACT Because of the existence of severely defective humans it is commonly held that whatever consideration is due to all humans is also due to many other animals, and that therefore speciesism, or the readiness to prefer the interest of humans to those of other animals, is unjustified. After criticism of this reasoning a 'naturalised' speciesism, acknowledging, for example, the affinities between species, is articulated and defended. A key to this defence is the separation of the task of specifying morally significant differences between humans and other animals from the task of justifying the extension of consideration to defective humans. The conclusion is that more traditional vices than speciesism are chiefly to blame for the shabby treatment of animals by humans.     

INEVITABLE HUMANS: SIMON CONWAY MORRIS'S EVOLUTIONARY PALEONTOLOGY

Abstract. Simon Conway Morris, noted Cambridge University paleontologist, argues that in evolutionary natural history humans (or beings rather like humans) are an inevitable outcome of the developing speciating processes over millennia; humans are “inherent” in the system. This claim, in marked contrast to claims about contingency made by other prominent paleontologists, is based on numerous remarkable convergences—similar trends found repeatedly in evolutionary history. Conway Morris concludes approaching a natural theology. His argument is powerful and informed. But does it face adequately the surprising events in such history, particularly notable in unexpected co‐options that redirect the course of life? The challenge to understand how humans are both on a continuum with other species and also utterly different remains a central puzzle in paleontology.     

How horses (Equus caballus) see the world: humans as significant “objects”

This study aimed to determine whether horses have a kind of memory of humans (based on previous interactions), leading to a general significance of humans revealed by their reactions to humans in subsequent interactions. Subjects were 59 adult horses used to interact daily with humans. Three types of behavioural tests involving an unknown experimenter evaluated three possibly different memorized types of human–animal interactions (not work-related, using work-related objects, unfamiliar working task). We also performed standardized observations of routine interactions between each horse and its familiar handler (caretaker). To get a broad overview of the horses’ reactions to humans, we recorded both investigative and aggressive behaviours during the tests, representing respectively a “positive” and a “negative” memory of the relationship. Whereas correlations between tests revealed a general perception of humans as either positive or negative, unusual tests, i.e. that are not usually performed, elicited more positive reactions. Moreover, some horses reacted positively to a motionless person in their box, but negatively when this same person approached them, for example for halter fitting. Overall, aggressive reactions were more reliable indicators of the relationship than positive reactions, both between tests and between familiar and unfamiliar humans. Our results also show generalization of the perception of humans. These results support our hypothesis that perception of humans by horses may be based on experience, i.e. repeated interactions. Altogether, our results support the hypothesis that horses can form a memory of humans that impacts their reactions in subsequent interactions.     

A dog's got personality: a cross-species comparative approach to personality judgments in dogs and humans

This research offers a blueprint for how a cross-species comparative approach can be realized empirically. In a single design, parallel procedures and instruments were used in 2 species, dogs (Canis familiaris) and humans (Homo sapiens), to test whether personality differences exist and can be judged in dogs as accurately as in humans. Personality judgments of humans and dogs were compared on 3 accuracy criteria: internal consistency, consensus, and correspondence. Results showed that, on all 3 criteria, judgments of dogs were as accurate as judgments of humans. These findings are consistent with the evolutionary continuity hypothesis and suggest an important conclusion not widely considered by either personality or animal researchers: Personality differences do exist and can be measured in animals other than humans.     

Rationality and reflective equilibrium

Cohen (1981) and others have made an interesting argument for the thesis that humans are rational: normative principles of reasoning and actual human reasoning ability cannot diverge because both are determined by the same process involving our intuitions about what constitutes good reasoning as a starting point. Perhaps the most sophisticated version of this argument sees reflective equilibrium as the process that determines both what the norms of reasoning are and what actual cognitive competence is. In this essay, I will evaluate both the general argument that humans are rational and the reflective equilibrium argument for the same thesis. While I find both accounts initially appealing, I will argue that neither successfully establishes that humans are rational.     

Moral Agency in Other Animals

Some philosophers have argued that moral agency is characteristic of humans alone and that its absence from other animals justifies granting higher moral status to humans. However, human beings do not have a monopoly on moral agency, which admits of varying degrees and does not require mastery of moral principles. The view that all and only humans possess moral agency indicates our underestimation of the mental lives of other animals. Since many other animals are moral agents (to varying degrees), they are also subject to (limited) moral obligations, examples of which are provided in this paper. But, while moral agency is sufficient for significant moral status, it is by no means necessary.     

NATURE, GOD'S GREAT PROJECT

Abstract. Scientific understandings suggest very strongly that humans are related to the rest of nature in ways that are expressed both by metaphors of genetic kinship and by ecological interrelatedness. The image of genetic kinship is the more intense image, and also the most likely to cause discomfort for Western traditions. Both secular critical reason and Western religious traditions favor images that portray the relation of humans to nature in terms of separation, domination, and stewardship. At best they are ambivalent toward portrayals of a more intense relatedness. In order to best serve our self-understandings, we must recognize (1) our intrinsic kinship with the rest of nature; (2) that our purpose as humans is to serve nature; (3) that we are preparers for nature's future; (4) that our highest calling as humans is to discern the dimensions of ultimacy in nature and to conceptualize them. In this, we follow God's own pattern of investing in nature as the greatest project.     

Rational maximizing by humans (Homo sapiens) in an ultimatum game

In the human mini-ultimatum game, a proposer splits a sum of money with a responder. If the responder accepts, both are paid. If not, neither is paid. Typically, responders reject inequitable distributions, favoring punishing over maximizing. In Jensen et al.’s (Science 318:107–109, 2007) adaptation with apes, a proposer selects between two distributions of raisins. Despite inequitable offers, responders often accept, thereby maximizing. The rejection response differs between the human and ape versions of this game. For humans, rejection is instantaneous; for apes, it requires 1 min of inaction. We replicate Jensen et al.’s procedure in humans with money. When waiting 1 min to reject, humans favor punishing over maximizing; however, when rejection requires 5 min of inaction, humans, like apes, maximize. If species differences in time horizons are accommodated, Jensen et al.’s ape data are reproducible 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.     

Vestibular stimulation affects optic-flow sensitivity

Typically, multiple cues can be used to generate a particular percept. Our area of interest is the extent to which humans are able to synergistically combine cues that are generated when moving through an environment. For example, movement through the environment leads to both visual (optic-flow) and vestibular stimulation, and studies have shown that non-human primates are able to combine these cues to generate a more accurate perception of heading than can be obtained with either cue in isolation. Here we investigate whether humans show a similar ability to synergistically combine optic-flow and vestibular cues. This was achieved by determining the sensitivity to optic-flow stimuli while physically moving the observer, and hence producing a vestibular signal, that was either consistent with the optic-flow signal, eg a radially expanding pattern coupled with forward motion, or inconsistent with it, eg a radially expanding pattern with backward motion. Results indicate that humans are more sensitive to motion-in-depth optic-flow stimuli when they are combined with complementary vestibular signals than when they are combined with conflicting vestibular signals. These results indicate that in humans, like in nonhuman primates, there is perceptual integration of visual and vestibular signals.     

Wild birds recognize individual humans: experiments on magpies, <Emphasis Type="Italic">Pica pica</Emphasis>

The ability to distinguish among heterospecific individuals has been reported in only a few animal species. Humans can be viewed as a special type of heterospecifics because individuals differ widely in behavior, ranging from non-threatening to very threatening toward animals. In this study, we asked whether wild magpies can recognize individual humans who had accessed their nests. We compared the behavior of breeding pairs toward individual humans before and after the humans climbed up to the birds’ nests, and also toward climbers and non-climbers. We have evidence for (i) aggressive responses of the magpie pairs toward humans who had repeatedly accessed their nests (climbers) and a lack of response to humans who had not accessed the nest (non-climbers); (ii) a total lack of scolding responses toward climbers by magpie pairs whose nests had not been accessed; (iii) a selective aggressive response to the climber when a climber and a non-climber were presented simultaneously. Taken together, these results suggest that wild magpies can distinguish individual humans that pose a threat to their nests from humans that have not behaved in a threatening way. The magpie is only the third avian species, along with crows and mockingbirds, in which recognition of individual humans has been documented in the wild. Here, we propose a new hypothesis (adopted from psychology) that frequent previous exposure to humans in urban habitats contributes to the ability of birds to discriminate among human individuals. This mechanism, along with high cognitive abilities, may predispose some species to learn to discriminate among human individuals. Experimental tests of these two mechanisms are proposed.     

社会认知的神经基础

人类的社会技能高于其它任何动物,能够形成对社会环境的高级表征,并能利用这些表征进行十分灵活的推理判断。但是社会认知的神经基础目前仍不十分明了。来自于人类和其它灵长类动物的研究已经发现有一些脑结构（如杏仁核、前额叶、颞上沟、扣带前回等）在社会认知中起着特殊重要的作用。此外,越来越多的研究表明其它一些脑区结构（如右侧躯体体感区、岛叶、基底节、白质等）也共同参与社会认知加工过程。文章对近年来关于社会认知的神经基础研究做了较为详细的综述。     

What makes us human (Homo sapiens)? The challenge of cognitive cross-species comparison

Two major theoretical approaches have dominated the quest for uniquely human cognitive abilities: a developmentalist approach stressing the importance of environmental and social conditions, and a predominant approach in experimental and comparative psychology, the deterministic approach suggesting the effect of environmental and social conditions to be minimal. As a consequence, most claims of human cognitive uniqueness are based on comparisons of White middle class Westerner humans (Homo sapiens) with captive chimpanzees (Pan troglodytes). However, humans are much more than only White middle class Westerners, and chimpanzees are much more than only captives. A review of some data available on different populations of humans and chimpanzees reveals that only the predictions of the developmentalist approach are supported. In addition, systematic biases are too often introduced in experiment protocols when comparing humans with apes that further cast doubts on cross-species comparisons. The author argues that only with consideration of within-species population differences in the cognitive domains and the use of well-matched cross-species experimental procedures will an objective understanding of the different cognitive abilities between species emerge. This will require a shift in the theoretical approach adopted by many in experimental and comparative psychology.     

Interpersonal distance in immersive virtual environments

Digital immersive virtual environment technology (IVET) enables behavioral scientists to conduct ecologically realistic experiments with near-perfect experimental control. The authors employed IVET to study the interpersonal distance maintained between participants and virtual humans. In Study 1, participants traversed a three-dimensional virtual room in which a virtual human stood. In Study 2, a virtual human approached participants. In both studies, participant gender, virtual human gender, virtual human gaze behavior, and whether virtual humans were allegedly controlled by humans (i.e., avatars) or computers (i.e., agents) were varied. Results indicated that participants maintained greater distance from virtual humans when approaching their fronts compared to their backs. In addition, participants gave more personal space to virtual agents who engaged them in mutual gaze. Moreover, when virtual humans invaded their personal space, participants moved farthest from virtual human agents. The advantages and disadvantages of IVET for the study of human behavior are discussed.     

EVOLUTION,CULTURE, AND SIN: RESPONDING TO PHILIP HEFNER'S PROPOSAL

Abstract. In his recent book, The Human Factor, Philip Hefner proposes to deepen theological understanding of the natural world and the place of humans within it. He describes humans as products of converging streams of genes and culture, and as possessors of freedom that requires them to be “created cocreators.” In accordance with the requirements of “the way things really are” (God), humans are to become divine agents in enlarging the realm of freedom in the world through self-sacrificing altruism. While Hefner's insights are admirable, his work could be viewed, in part, as a covert expression of nineteenth century liberal beliefs in progress. In fact, human culture and freedom are more ambiguous products of both good and evil, and hence we must take more cognizance of the pervasiveness of what theology has termed sin.     

Testosterone affects gaze aversion from angry faces outside of conscious awareness

Throughout vertebrate phylogeny, testosterone has motivated animals to obtain and maintain social dominance-a fact suggesting that unconscious primordial brain mechanisms are involved in social dominance. In humans, however, the prevailing view is that the neocortex is in control of primordial drives, and testosterone is thought to promote social dominance via conscious feelings of superiority, indefatigability, strength, and anger. Here we show that testosterone administration in humans prolongs dominant staring into the eyes of threatening faces that are viewed outside of awareness, without affecting consciously experienced feelings. These findings reveal that testosterone motivates social dominance in humans in much the same ways that it does in other vertebrates: involuntarily, automatically, and unconsciously.