Tentative evidence for inequity aversion to unequal work-effort but not to unequal reward distribution in Goffin's cockatoos

One hallmark in the evolution of cooperation is the ability to evaluate one's own payoff for a task against that of another person. To trace its evolutionary history, there has recently been a surge in comparative studies across different species. In non-human animals, evidence of inequity aversion has so far been identified in several primate species, dogs, and rats. Research in birds revealed mixed findings so far: among corvids, crows and ravens did react sensitively to unequal payoffs and work-effort, while New Caledonian crows did not. Among psittacids, kea were studied so far: Yet, despite the fact that they live in large, hierarchically organized social groups that show complex interactions, they did not show a significant reaction to inequitable payoffs. Here we tested for the first time a Cacatua, the Goffin's cockatoo, using a standardized token exchange paradigm in which first the partner and then the subject could exchange a token for a food reward. Our results show that subjects did not react to unequal reward distributions. However, in comparison to the Equity Condition, the likelihood to exchange was lower in the condition in which the partner received the same reward as a gift (without having to work for it) whereas the subject had to perform a task involving substantial work-effort, suggesting that the Goffin's cockatoos do react aversively to work-effort inequity. In a follow-up experiment, subjects never received a reward but observed a conspecific receive a high-quality reward depending on condition. We found again no evidence for an aversion for the unequal reward distribution, but only that, independent of condition, subjects quickly lost their motivation to participate due to not receiving a reward. In summary, Goffins showed some sensitivity to increased unequal work-effort, but did not react to unequal reward distribution.     

Punishment is strongly motivated by revenge and weakly motivated by inequity aversion

There are two broad functional explanations for second-party punishment: fitness-leveling and deterrence. The former suggests that people punish to reduce fitness differences, while the latter suggests that people punish in order to reciprocate losses and deter others from inflicting losses on them in the future. We explore the relative roles of these motivations using a pre-registered, two-player experiment with 2426 US participants from Amazon Mechanical Turk. Participants played as the “responder” and were assigned to either a Take or Augment condition. In the Take condition, the “partner” could steal money from the responder's bonus or do nothing. In the Augment condition, the partner could augment the responder's bonus by giving them money at no cost to themselves or do nothing. We also manipulated the responders' starting endowments, such that after the partner's decision, responders experienced different payoff outcomes: advantageous inequity, equality, or varying degrees of disadvantageous inequity. Responders then decided whether to pay a cost to punish the partner. Punishment was clearly influenced by theft and was most frequent when theft resulted in disadvantageous inequity. However, people also punished in the absence of theft, particularly when confronted with disadvantageous inequity. While the effect of inequity on punishment was small, our results suggest that punishment is motivated by more than just the desire to reciprocate losses. These findings highlight the multiple motivations undergirding punishment and bear directly on functional explanations for the existence of punishment in human societies.     

Attending to the outcome of others: disadvantageous inequity aversion in male capuchin monkeys (Cebus apella)

Brosnan and de Waal [Nature 425:297-299, 2003] reported that capuchin monkeys responded negatively to unequal reward distributions between themselves and another individual when comparing their own rewards with that of their partner. It was suggested that social emotions provided the underlying motivation for such behavior and that this inequity aversion is specific to the social domain. However, alternative hypotheses such as the "frustration effect" or the "food expectation hypothesis" may provide more parsimonious explanations for Brosnan and de Waal's [Nature 425:297-299] results, while others have argued that these findings are not congruent with the Fehr-Schmidt inequity aversion model cited by the authors. The claim that inequity aversion behavior is specific to the social domain has also been questioned, as primates also develop expectations about rewards in the absence of partners, and react negatively when those expectations are violated. In this study, a modified Dictator game was used to investigate whether capuchins would exhibit either disadvantageous inequity aversion behavior or reference-dependent expectancy violation in social and nonsocial conditions, respectively. When given the choice between an equitable and an inequitable outcome, the subjects showed disadvantageous inequity aversion behavior, choosing the equitable outcome significantly more in the social condition. In the nonsocial condition, however, subjects did not show negative expectancy violation resulting from the formation of reference-dependent expectations, choosing the equitable outcome at chance levels. These results suggest that capuchins attend to differential payoffs and that they are averse to inequity, which is disadvantageous to themselves.     

Activity enhancement of Zygogramma bicolorata,a biocontrol agent of Parthenium hysterophorus,by temperature regulated diapause aversion

Diapause is a unique strategy of dormancy in insects to avoid unfavourable conditions. The exotic beetle Zygogramma bicolorata, is an effective biological control agent of Parthenium hysterophorus in India, Adults diapause in soil during December to May. As a result, there is delay in its effectiveness on the plant that reaches to flowering and seed production by the time the beetle is able to build up its population after emerging from diapause. Therefore, a study was conducted to explore possibilities of diapause aversion by temperature regulation. Results indicated that exposure of newly emerged adults to heat treatment of 35°C and to low temperature of 10°C could reduce diapause in Z. bicolorata. The low temperature can also be used as a medium for the storage of the mass reared beetles for a long time without having negative effect on their longevity and fecundity.     

Rapid,reverse reciprocity failure for phytochrome control of its own accumulation*

Abstract. Fluence–response curves have been obtained for end-of-day far-red stimulation and red reversal of phytochrome accumulation in leaves of light-grown corn during darkness following a white-light period. The response to end-of-day far-red, but not to R, shows rapid, reverse reciprocity failure which cannot be explained by escape from photoreversibility. Because the Pfr/Ptot established by long, low fluence rate and short, high fluence rate exposures of the same total fluence is the same and can lead to vastly different responses, explanations for this phenomenon based simply on Pfr levels or Pfr/Ptot are inadequate. Reciprocity failure for end-of-day far-red is not necessarily coupled to reciprocity failure for red reversal of the far-red effect. The two phenomena must stem from different causes.     

Conditioned taste aversion by lithium and saline: a methodological evaluation

Conditioned taste aversion (CTA) to saccharin induced by orallithium chloride and normal saline were investigated in 270Wistar rats in a CTA paradigm. They were trained to drink for20-min sessions per day in a two-bottle choice, providing saccharinand water simultaneously. Saccharinn neophobia was replacedby a preference with two more exposures. Saccharin was withheldfor 2 days following force-feeding of lithium or saline in orderto assess lithium-illness. Lithium-fed rats showed signs ofillness followed by a strong CTA to saccharin persisting for3–4 days. Saline-fed rats did not suffer from any illnessbut showed a weak and inconsistent CTA lasting for a day ortwo. Scopolamine injections prior to force-feeding did not affectthe pattern of aversion in either group, but significantly suppressedthe revocation of CTA in the saline-fed rats by a second oraldose of saline.     

A comparative tool for the validity of rate kinetics in ion channels by Onsager reciprocity theorem

The precise form of the rate constant functions of ion channels is very crucial for reproducing the electrophysiological behavior. Therefore, how well they account for experimental data plays an important role in the behavior of the model. In this study, we derive kinetic coefficients of activation and inactivation gates in ion channels by Onsager reciprocity theorem for an ensemble of gating particles, and propose that the obtained kinetic coefficients can be used as a comparative tool for the empirical validity of fitted rate constant functions to experimental data. We also illustrate its applicability based on the activation and inactivation kinetics of T-type calcium channel in thalamic relay neurons. We show that the shape of the steady-state curve by itself seems to be a poor indicator of the functional form of the rate functions, but the time constant curves reflect considerable variation depending on the particular form of the rate functions, and that the kinetic coefficients related to the time constants provide a powerful tool to determine the empirical validity of the fitted rate constants.     

Blocking of acquisition of a taste aversion by a context experienced prior to the taste

This experiment tested the proposal that events taking place before a rat has access to a taste can proactively interfere with acquisition of an aversion to the taste when this has been followed by lithium chloride injection. Rats were initially given context discrimination whereby placement in one distinctive context (target) was followed by lithium injection, while placement in a second context (safe) was followed by saline injection. In the subsequent 1-trial taste conditioning session, rats were first placed in either their target context (Blocking group), their safe context (Control-Safe group) or a neutral context (Control-Neutral group), then given access to sucrose and 30 min later were injected with lithium. Subsequent tests of sucrose intakes revealed a blocking effect. These results indicate that proactive interference with taste aversion learning by a context can occur that is unlikely to be based on generalization decrement.     

Reciprocity,culture and human cooperation: previous insights and a new cross-cultural experiment

Understanding the proximate and ultimate sources of human cooperation is a fundamental issue in all behavioural sciences. In this paper, we review the experimental evidence on how people solve cooperation problems. Existing studies show without doubt that direct and indirect reciprocity are important determinants of successful cooperation. We also discuss the insights from a large literature on the role of peer punishment in sustaining cooperation. The experiments demonstrate that many people are ‘strong reciprocators’ who are willing to cooperate and punish others even if there are no gains from future cooperation or any other reputational gains. We document this in new one-shot experiments, which we conducted in four cities in Russia and Switzerland. Our cross-cultural approach allows us furthermore to investigate how the cultural background influences strong reciprocity. Our results show that culture has a strong influence on positive and in especially strong negative reciprocity. In particular, we find large cross-cultural differences in ‘antisocial punishment’ of pro-social cooperators. Further cross-cultural research and experiments involving different socio-demographic groups document that the antisocial punishment is much more widespread than previously assumed. Understanding antisocial punishment is an important task for future research because antisocial punishment is a strong inhibitor of cooperation.     

Tolerant food sharing and reciprocity is precluded by despotism among bonobos but not chimpanzees

Tolerant food sharing among human foragers can largely be explained by reciprocity. In contrast, food sharing among chimpanzees and bonobos may not always reflect reciprocity, which could be explained by different dominance styles: in egalitarian societies reciprocity is expressed freely, while in more despotic groups dominants may hinder reciprocity. We tested the degree of reciprocity and the influence of dominance on food sharing among chimpanzees and bonobos in two captive groups. First, we found that chimpanzees shared more frequently, more tolerantly, and more actively than bonobos. Second, among chimpanzees, food received was the best predictor of food shared, indicating reciprocal exchange, whereas among bonobos transfers were mostly unidirectional. Third, chimpanzees had a shallower and less linear dominance hierarchy, indicating that they were less despotic than bonobos. This suggests that the tolerant and reciprocal sharing found in chimpanzees, but not bonobos, was made possible by the absence of despotism. To investigate this further, we tested the relationship between despotism and reciprocity in grooming using data from an additional five groups and five different study periods on the main groups. The results showed that i) all chimpanzee groups were less despotic and groomed more reciprocally than bonobo groups, and ii) there was a general negative correlation between despotism and grooming reciprocity across species. This indicates that an egalitarian hierarchy may be more common in chimpanzees, at least in captivity, thus fostering reciprocal exchange. We conclude that a shallow dominance hierarchy was a necessary precondition for the evolution of human‐like reciprocal food sharing. Am J Phys Anthropol 143:41–51, 2010. © 2010 Wiley‐Liss, Inc.     

A study of indirect reciprocity involving a reputation system or a simple tag system in a one-shot, multi-player game

The possibility of the evolution of cooperation backed by indirect reciprocity (IDR) in a one-shot, multi-player game is investigated focusing on two mechanisms. First of all, the reputation system with image score (RS with IS), as proposed by Nowak and Sigmund [Nowak, M.A., Sigmund, K., 1998. Evolution of indirect reciprocity by image scoring. Nature 393, 573–577], is investigated in various game structures. A numerical experiment demonstrates that the RS with IS is a robust mechanism for the support of IDR in various dilemma games, but whose effectiveness decreases with an increase in the number of players in a game. It is fair to say that the RS is an information mapping function to relate between player's cooperative fraction on his action and IS. As the second mechanism, a simple tag system which could be applicable to animals having no cognitive complexity is considered to support IDR. Computer simulations of the tag system's strategy for invading a population initially consisting of AllD, AllC, and Random strategies suggest several novel facts. The Tag strategy with plausible crossover and mutation probabilities can only invade to settle down if the game structure is not Trivial and contains a moderate dilemma. The Tag strategy's evolutionary competition takes place mainly in the presence of the AllD strategy. During the competition, the Tag strategy frequently metamorphoses to shake off the AllD strategy, but stops after winning in order to avoid a shrinking payoff due to fragmentation.     

Innovating inequity: if race is a technology,postracialism is the genius bar

ABSTRACT

In this essay I posit race as a kind of technology, one that creates parallel universes and premature death, requiring routine maintenance and upgrade. I suggest that David Theo Goldberg’s Are We Postracial Yet? is a story of innovation that expertly exposes the trade secrets of the social production of race. I argue that not only are technological and social innovation metaphorically linked; technoscience is also one of the most effective conduits for reproducing racial inequality, and so I extend Goldberg’s analysis to address the central role of science and technology in modern statecraft and racecraft. Finally, if postracial innovators are busily refurbishing racism to remake inequality, then those who seek radical transformation in the other direction, towards freedom and justice, must re-examine the default settings, rather than the routine breakdowns, of social life.     

Defectors,not norm violators,are punished by third-parties

Punishment of defectors and cooperators is prevalent when their behaviour deviates from the social norm. Why atypical behaviour is more likely to be punished than typical behaviour remains unclear. One possible proximate explanation is that individuals simply dislike norm violators. However, an alternative possibility exists: individuals may be more likely to punish atypical behaviour, because the cost of punishment generally increases with the number of individuals that are punished. We used a public goods game with third-party punishment to test whether punishment of defectors was reduced when defecting was typical, as predicted if punishment is responsive to norm violation. The cost of punishment was fixed, regardless of the number of players punished, meaning that it was not more costly to punish typical, relative to atypical, behaviour. Under these conditions, atypical behaviour was not punished more often than typical behaviour. In fact, most punishment was targeted at defectors, irrespective of whether defecting was typical or atypical. We suggest that the reduced punishment of defectors when they are common might often be explained in terms of the costs to the punisher, rather than responses to norm violators.     

Genetic studies of a behavioral mutant,glucose aversion,in the German cockroach (Dictyoptera: Blattellidae)

Glucose aversion(Glu) is a naturally occurring behavioral mutant of the German cockroach,Blattella germanica. Earlier work suggested thatGlu is a semidominant autosomal trait. Further study was undertaken to place the mutant gene in the linkage map of the species and expand the information on its genetic basis. Linkage was investigated in test crosses with morphologic markers for 7 of the 11 autosomal linkage groups. Assays for amounts of glucose ingested per individual confirmed the expected low consumption ofGlu heterozygotes(Glu/+) and that continuous selection pressure on the parental strain had resulted in near- and probably complete homozygosity forGlu. Glu genotypes were identified by means of a discriminating ingestion that separated heterozygotes from wild type(Glu+). Variations in expression indicate that genetic factors influence food consumption inB. germanica. Positive results were obtained in linkage tests ofGlu with ruby eye(ru), indicating that theGlu locus lies in linkage group VIII (chromosome 9), a group notable for mutants that apparently result in the expression of latent, highly primitive development pathways.     

Declining acceptability of a food plant for the polyphagous grasshopper Schistocerca americana: the role of food aversion learning

ABSTRACT Successive contacts with a food that was initially acceptable to the acridid Schistocerca americana (Drury) (Orthoptera: Acrididae) were monitored. It was found that acceptability, as measured by meal length, declined with experience until the food, spinach, was completely rejected. Reduced acceptability of spinach was maintained even after feeding for three meals on a fully acceptable and suitable food, a period of 2–3 h. Experiments with spinach-filled capsules placed in the gut suggested that the decline in acceptability was not due to direct feedback from the gut or haemolymph on the sensory or feeding control systems. Food aversion learning is indicated as the mechanism underlying the decline in acceptability.     

Human splicing factor SF3a, but not SF1, is essential for pre-mRNA splicing in vivo

The three subunits of human splicing factor SF3a are essential for the formation of the functional 17S U2 snRNP and prespliceosome assembly in vitro. RNAi-mediated depletion indicates that each subunit is essential for viability of human cells. Knockdown of single subunits results in a general block in splicing strongly suggesting that SF3a is a constitutive splicing factor in vivo. In contrast, splicing of several endogenous and reporter pre-mRNAs is not affected after knockdown of SF1, which functions at the onset of spliceosome assembly in vitro and is essential for cell viability. Thus, SF1 may only be required for the splicing of a subset of pre-mRNAs. We also observe a reorganization of U2 snRNP components in SF3a-depleted cells, where U2 snRNA and U2-B' are significantly reduced in nuclear speckles and the nucleoplasm, but still present in Cajal bodies. Together with the observation that the 17S U2 snRNP cannot be detected in extracts from SF3a-depleted cells, our results provide further evidence for a function of Cajal bodies in U2 snRNP biogenesis.