Biological Markets
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Biological Markets
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Falco, Albinet, Rattat, Paul & Fabre (2019). Being the chosen one: social inclusion modulates decisions in the ultimatum game. An ERP study. Social Cognitive and Affective Neuroscience

Falco, Albinet, Rattat, Paul & Fabre (2019). Being the chosen one: social inclusion modulates decisions in the ultimatum game. An ERP study. Social Cognitive and Affective Neuroscience | Biological Markets | Scoop.it

Abstract: In the present study, participants played a modified ultimatum game simulating a situation of inclusion/exclusion, in which either the participant or a rival could be selected to play as the responder. This selection was made either randomly by a computer (i.e. random pairing mode) or by the proposer (i.e. choice mode), based on physical appearance. Being chosen by the proposer triggered positive reciprocal behavior in participants, who accepted unfair offers more frequently than when they had been selected by the computer. Independently of selection mode, greater P200 amplitudes were found when participants received fair offers than when they received unfair offers and when unfair shares were offered to their rivals rather than to them, suggesting that receiving fair offers or observing a rival’s misfortune was rewarding for participants. While participants generally showed more interest in the offers they themselves received (i.e. greater P300 responses to these offers), observing their rivals receive fair shares after the latter had been chosen by the proposer triggered an increase in P300 amplitude likely to reflect a feeling of envy. This study provides new insights into both the cognitive and affective processes underpinning economic decision making in a context of social inclusion/exclusion.


Keywords: ultimatum game, social inclusion/exclusion, biological market, responder, ERP

Ronald Noë's insight:
Partner choice in an ultimatum game setting: either the proposer or a computer chooses the responder among two candidates. Remarkable is that the proposer chooses on physical appearance rather than on a criterion that could eventually be (more directly) linked to strategic behaviour.
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Austin, Horack & Dunlap (2018). Choice in a floral marketplace: the role of complexity in bumble bee decision-making. Behavioral Ecology

Austin, Horack & Dunlap (2018). Choice in a floral marketplace: the role of complexity in bumble bee decision-making. Behavioral Ecology | Biological Markets | Scoop.it

Abstract: Animals have evolved in complex, heterogeneous environments. Thus, decision-making behavior is likely affected by a diversity of cooccurring community-level traits. Here, we investigate how 3 co-occurring traits of floral communities—the number of flower types, reliability that flowers are associated with a reward, and signal complexity of flowers—affect bumble bee (Bombus impatiens) decision- making. We used arrays of artificial flowers in a full factorial experimental design to assess floral selectivity (preference and constancy), foraging efficiency, and decision latency in foraging bumble bees. We find that our environmental traits uniquely affect each of these behavioral variables, revealing the intricate, yet biologically significant ways that co-occurring environmental traits can affect behavior. Floral selectivity, but not foraging efficiency, is increased by a greater number of choices. Decision latency is greatest when bees are inexperienced foraging in environments with high choice number. Collectively taken, we argue that these results suggest a cost to deciding among many choices, which promotes choice fidelity when many options are present. We suggest that these results have implications for theory on decision-making and selection in biological markets, while demonstrating the importance of studying interactions between naturally co-occurring traits.


Keywords: Bombus, constancy, decision-making, floral selectivity, foraging theory, rationality theory

Ronald Noë's insight:
The authors explore the effect of having more - and more complex - choices on foraging bumblebees. They compare their findigns with the results of studies of (human) consumer behaviour which were confronted with either few or many choices between comparable products in supermarkets.

I think the authors are correct in claiming that their results are relevant to many other types of biological markets in with the members of either or both trader classes have multiple choices based on multiple cues of varying complexity and reliability.
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Dreyer, Spitz, Kanonenberg ... (2019). Nutrient exchange in arbuscular mycorrhizal symbiosis from a thermodynamic point of view. New Phytologist

Dreyer, Spitz, Kanonenberg ... (2019). Nutrient exchange in arbuscular mycorrhizal symbiosis from a thermodynamic point of view. New Phytologist | Biological Markets | Scoop.it
Abstract: To get insights into the dynamics of nutrient exchange in arbuscular mycorrhizal (AM) symbiosis, we modelled mathematically the two-membrane system at the plant–fungus interface and simulated its dynamics. In computational cell biology experiments, the full range of nutrient transport pathways was tested for their ability to exchange phosphorus (P) / carbon (C) / nitrogen (N) sources. As a result, we obtained a thermodynamically justified, independent, and comprehensive model of the dynamics of the nutrient exchange at the plant–fungus contact zone. The predicted optimal transporter network coincides with the transporter set independently confirmed in wet-lab experiments previously, indicating that all essential transporter types have been discovered. The thermodynamic analyses suggest that phosphate is released from the fungus via proton-coupled phosphate transporters rather than anion channels. Optimal transport pathways, such as cation channels or proton-coupled symporters, shuttle nutrients along with a positive charge across the membranes. Only in exceptional cases, also the electroneutral transport via diffusion facilitators appears plausible. The thermodynamic models presented here can be generalised and adapted to other forms of mycorrhiza and open the door for future studies combining wet-lab experiments with computational simulations to obtain a deeper understanding of the investigated phenomena.

Keywords: computational cell biology nutrient transport plant–fungus interaction plant biophysics modelling
Ronald Noë's insight:
The following quote from the paper gives the reason why you see this here: "The question “How harmonious are AM symbioses?” is still widely discussed (Smith & Smith, 2015), and each experiment approaches this topic from a different perspective. A reasonable and rather successful concept describes AM symbiosis as a biological market (Kiers et al., 2011; Hammerstein & Noë, 2016; Noë & Kiers, 2018). In this context, our model now explains the thermodynamic basis of the underlying market forces".

It is my habit to list all authors of a paper, but in this case that didn't fit. Here is the full list: Dreyer, I., O. Spitz, K. Kanonenberg, K. Montag, M. Handrich, S. Ahmad, S. Schott-Verdugo, C. Navarro-Retamal, M. E. Rubio-Meléndez, J. L. Gomez-Porras, J. Riedelsberger, M. A. Molina-Montenegro, A. Succurro, A. Zuccaro, S. B. Gould, P. Bauer, L. Schmitt and H. Gohlke
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Berthier & Semple (2018). Observing grooming promotes affiliation in Barbary macaques. Proceedings of the Royal Society B 285(1893), 20181964

Berthier & Semple (2018). Observing grooming promotes affiliation in Barbary macaques. Proceedings of the Royal Society B 285(1893), 20181964 | Biological Markets | Scoop.it
Abstract: Observing friendly social interactions makes people feel good and, as a result, then act in an affiliative way towards others. Positive visual contagion of this kind is common in humans, but whether it occurs in non-human animals is unknown. We explored the impact on female Barbary macaques of observing grooming, a behaviour that physiological and behavioural studies indicate has a relaxing effect on the animals involved. We compared females' behaviour between two conditions: after observing conspecifics groom, and in a matched control period. We found that observing grooming was associated with reduced behavioural indicators of anxiety, suggesting that seeing others groom is, in itself, relaxing. Observing grooming was also associated with a shorter latency to becoming involved in a grooming bout (and higher likelihood both of initiating that bout and being the groomer rather than groomee), and with elevated rates of other affiliative behaviours. These results provide evidence for positive visual contagion; this phenomenon may contribute fundamentally to group cohesion not just in this species, but also in the many mammal and bird species where grooming occurs. Our study highlights the importance of exploring social behaviour beyond the level of the interacting individuals, within the broader social context where it occurs.

Keywords: cooperation social audience eavesdrop social network primate
Ronald Noë's insight:
Could/should be of interest to those working on 'grooming markets', notably in primates
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Albrecht, Hagge, Schabo, Schaefer & Farwig (2018). Reward regulation in plant–frugivore networks requires only weak cues. Nature Communications, 9(1), 4838

Albrecht, Hagge, Schabo, Schaefer & Farwig (2018). Reward regulation in plant–frugivore networks requires only weak cues. Nature Communications, 9(1), 4838 | Biological Markets | Scoop.it

A challenge for mutualists is that partner cue reliability is often low. Here, the authors show that though fruit brightness is weakly predictive of nutritional content, the diets of birds (e.g. migrants vs. residents) are structured by fruit brightness in alignment with expected nutritional needs.


Abstract: Theory assumes that fair trade among mutualists requires highly reliable communication. In plant–animal mutualisms the reliability of cues that indicate reward quality is often low. Therefore, it is controversial whether communication allows animal mutualists to regulate their reward intake. Here we show that even loose relationships between fruit brightness and nutritional rewards (r2 = 0.11–0.35) allow birds to regulate their nutrient intake across distinct European plant–frugivore networks. Resident, over-wintering generalist frugivores that interact with diverse plant species select bright, lipid-rich fruits, whereas migratory birds select dark, sugar- and antioxidant-rich fruits. Both nutritional strategies are consistent with previous physiological experiments suggesting that over-wintering generalists aim to maximize their energy intake, whereas migrants aim to enhance the build-up of body fat, their immune response and oxidative status during migration. Our results suggest that animal mutualists require only weak cues to regulate their reward intake according to specific nutritional strategies.

Ronald Noë's insight:
The paper shows that the reliability of cues of reward quality ('advertisements') don't have to be very reliable in order to make selection on quality through partner chocie work, as long as there are many partners to choose from (here notably the fruits of many plant species by generalist frugivorous birds) and the interaction is repeated (i.e. the same individual bird visists the same individual plant many times and hence checks the quality of its fruit repeatedly).

In the last sentence of their Discussion the authors explain themselves why this paper is listed here: "In a broader context, our results support the idea that, in analogy to human markets, plant–animal mutualistic networks can be considered as biological markets in which consumers rely on advertisement by producers to select those partners whose offer best matches their specific demands."
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Loverdo, & Viciana (2018). Cultural transmission and biological markets. Biology & Philosophy (via Philsci-Archive)

Loverdo, & Viciana (2018). Cultural transmission and biological markets. Biology & Philosophy (via Philsci-Archive) | Biological Markets | Scoop.it
Abstract: Active cultural transmission of fitness-enhancing behavior (sometimes called “teaching”) can be seen as a costly strategy: one for which its evolutionary stability poses a Darwinian puzzle. In this article, we offer a biological market model of cultural transmission that substitutes or complements existing kin selection-based proposals for the evolution of cultural capacities. We explicitly demonstrate how a biological market can account for the evolution of teaching when individual learners are the exclusive focus of social learning (such as in a fast-changing environment). We also show how this biological market can affect the dynamics of cumulative culture. The model works best when it is difficult to have access to the observation of the behavior without the help of the actor. However, in contrast to previous non-mathematical hypotheses for the evolution of teaching, we show how teaching evolves even when innovations are insufficiently opaque and therefore vulnerable to acquisition by emulators via inadvertent transmission. Furthermore, teaching in a biological market is an important precondition for enhancing individual learning abilities

Keywords: Social learning Comparative advantage Teaching Cumulative culture Partner choice
Ronald Noë's insight:
The authors construct a biological market model based on the trade between teachers and learners in which the latter pay the teachers for aquired skills and knowledge by deference and an increase in prestige
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Phelps, Ng,  Musolesi & Russell (2018). Precise time-matching in chimpanzee allogrooming does not occur after a short delay. PLOS ONE, 13(9), e0201810

Phelps, Ng,  Musolesi & Russell (2018). Precise time-matching in chimpanzee allogrooming does not occur after a short delay. PLOS ONE, 13(9), e0201810 | Biological Markets | Scoop.it
Allogrooming is a key aspect of chimpanzee sociality and many studies have investigated the role of reciprocity in a biological market. One theoretical form of reciprocity is time-matching, where payback consists of an equal duration of effort (e.g. twenty seconds of grooming repaid with twenty seconds of grooming). Here, we report a study of allogrooming in a group of twenty-six captive chimpanzees (Chester Zoo, UK), based on more than 150 hours of data. For analysis, we introduce a methodological innovation called the “Delta scale”, which unidimensionally measures the accuracy of time-matching according to the extent of delay after the cessation of grooming. Delta is positive when reciprocation occurs after any non-zero delay (e.g. A grooms B and then B grooms A after a five second break) and it is negative when reciprocation begins whilst the original grooming has not yet ceased. Using a generalized linear mixed-method, we found evidence for time-matched reciprocation. However, this was true only for immediate reciprocation (Delta less than zero). If there was a temporal break in grooming between two members of a dyad, then there was no evidence that chimpanzees were using new bouts to retroactively correct for time-matching imbalances from previous bouts. Our results have implications for some of the cognitive constraints that differentiate real-life reciprocation from abstract theoretical models. Furthermore, we suggest that some apparent patterns of time-matched reciprocity may arise merely due to the law of large numbers, and we introduce a statistical test which takes this into account when aggregating grooming durations over a window of time.
Ronald Noë's insight:
(comment follows)
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Noë & Kiers (2018). "Mycorrhizal markets, firms, and co-ops." Trends in Ecology & Evolution (online) ScienceDirect

Noë & Kiers (2018). "Mycorrhizal markets, firms, and co-ops." Trends in Ecology & Evolution (online) ScienceDirect | Biological Markets | Scoop.it
Highlights:
 The mutualism between plants and arbuscular mycorrhizal fungi shows several market characteristics, including partner choice and adjustments to supply and demand.

Nutrient exchanges via communally formed arbuscules reduce trading costs the same way the formation of firms reduces ‘transaction costs’ on human markets.

Plants may discriminate among individual arbuscules, which are associated with subsets of the many nuclei found in a single fungus.

Subsets of polymorphic nuclei acting in unison are like co-ooperatives (‘co-ops’), institutions midway between independently acting traders and firms, that help traders coordinate their trading strategies and reduce competition among themselves.

Future models of the evolution of mycorrhizal mutualisms should concurrently incorporate their market-, firm-, and co-op-like characteristics.

Abstract: The nutrient exchange mutualism between arbuscular mycorrhizal fungi (AMFs) and their host plants qualifies as a biological market, but several complications have hindered its appropriate use. First, fungal ‘trading agents’ are hard to identify because AMFs are potentially heterokaryotic, that is, they may contain large numbers of polymorphic nuclei. This means it is difficult to define and study a fungal ‘individual’ acting as an independent agent with a specific trading strategy. Second, because nutrient exchanges occur via communal structures (arbuscules), this temporarily reduces outbidding competition and transaction costs and hence resembles exchanges among divisions of firms, rather than traditional trade on markets. We discuss how fungal nuclei may coordinate their trading strategies, but nevertheless retain some independence, similar to human co-operatives (co-ops).

Keywords: arbuscular mycorrhizal fungibiological market theorymycorrhizal mutualismnutrient exchange mutualism
Ronald Noë's insight:
I perhaps better don't comment on my own papers, except perhaps to say that this is a special paper in several ways, among other things because it is the fruit of a cooperation between a mycorrhiza expert and an (ex-) primatologist and because it came online the last day before my retirement.

I hope it contains a few ideas worth giving a bit of thought.
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Jiang, Xia, Wang, Zhang, Sun & Li (2018). Interchange between grooming and infant handling in female Tibetan macaques (Macaca thibetana). Zoological Research, 79-

Jiang, Xia, Wang, Zhang, Sun & Li (2018). Interchange between grooming and infant handling in female Tibetan macaques (Macaca thibetana). Zoological Research, 79- | Biological Markets | Scoop.it
Abstract: In some nonhuman primates, infants function as a social tool that can bridge relationships among group members. Infants are a desired commodity for group members, and mothers control access to them. The biological market theory suggests that grooming is widespread and represents a commodity that can be exchanged for infant handling. As a limited resource, however, the extent to which infants are interchanged between mothers (females with an infant) and non-mothers (potential handlers, females without an infant) remains unclear. In this study, we collected behavioral data to investigate the relationship between grooming and infant handling in free-ranging Tibetan macaques (Macaca thibetana) at Mt. Huangshan, China. Our results showed that females with infants received more grooming than females without infants. After her infant was handled, mother females received more grooming than they did during daily grooming interactions. However, with the increasing number of infants within the social group, both the grooming that mothers received and the grooming that non-mothers invested for handling infants decreased. We also found that non-mothers invested more time in grooming to gain access to younger infants than older infants. Our results provide evidence that infants are social commodities for both mother and non-mother females. Mothers use infants for obtain grooming and non-mothers use grooming to gain access to infants. The current study implies a bidirectional and complex interchange pattern between grooming and infant handling to compensate for the dyadic grooming disparity in non-human primates.

Keywords: Tibetan macaques (Macaca thibetana) Interchange Infant handling Grooming Biological market theory
Ronald Noë's insight:
Monkeys, and especially female monkeys, are very eager to inspect and handle newborn babies, but in many species they have to groom the mother in order to get permission to do so. The amount of grooming they have to spend most often depends on three factors: the dominance relationship between handler and mother (the 'grooming-up-the-hierarchy' effect; the age of the infant (the younger, the higher the value) and the number of infants relative to the number of would-be handlers (the effect of supply and demand). The authors of this study managed to show all three effects convincingly in the rarely studied Tibetian macaque.
The keyword they did not use, but under which this phenomenon is often described is 'baby market'.
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Ueno & Nakamichi (2018). Grooming facilitates huddling formation in Japanese macaques. Behavioral Ecology and Sociobiology, 72(6), 98

Ueno & Nakamichi (2018). Grooming facilitates huddling formation in Japanese macaques. Behavioral Ecology and Sociobiology, 72(6), 98 | Biological Markets | Scoop.it

Abstract: Some animals conserve body heat through physical contact with conspecifics (i.e., huddling) under cold climate conditions. However, the factors that promote huddle partner selection have not been clarified. We hypothesized that exchanging grooming for huddling is a beneficial strategy used by female Japanese macaques (Macaca fuscata) to withstand cold temperatures. In this study, we undertook focal sampling of 17 female macaques at Katsuyama, Okayama Prefecture, Japan, between April 2012 and March 2013. We used generalized linear mixed models and determined influential factors based on the Akaike information criterion. As a result, we found that female Japanese macaques were likely to participate in grooming interactions before huddling with adult females, but that they rarely did so before huddling with their young (1-year-old or younger) offspring. In particular, adult females tended to huddle with other adult females after unreciprocated grooming bouts. Moreover, they solicited return grooming less frequently when females huddled after grooming interactions than when they did not huddle after grooming interactions. Finally, we evaluated whether grooming improved huddling position. Immediately after grooming, females huddled at advantageous positions more often than they huddled without grooming, and relative benefit by huddling position in the groomer was likely to be larger than the groomee. In contrast, when females huddled after reciprocal grooming, females tended to huddle in positions that were equally beneficial to both females. Overall, our results suggest that female Japanese macaques, particularly those without young offspring, exchange grooming for huddling with other adult females.


Keywords: thermoregulation reciprocity cooperative behaviors young offspring primates

Ronald Noë's insight:
Over the years many commodities have been mentioned that primates can trade against their 'common currency' grooming: support in fights, tolerance in food patches, access to infants, sex etc. These authors add another one that is of special interest for a primate that lives in a cold climate: huddling.
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D'Souza, Shitut, Preussger, Yousif, Waschina & Kost (2018). Ecology and evolution of metabolic cross-feeding interactions in bacteria. Natural Product Reports, 35(5), 455-488

D'Souza, Shitut, Preussger, Yousif, Waschina & Kost (2018). Ecology and evolution of metabolic cross-feeding interactions in bacteria. Natural Product Reports, 35(5), 455-488 | Biological Markets | Scoop.it

Abstract: Literature covered: early 2000s to late 2017

Bacteria frequently exchange metabolites with other micro- and macro-organisms. In these often obligate cross-feeding interactions, primary metabolites such as vitamins, amino acids, nucleotides, or growth factors are exchanged. The widespread distribution of this type of metabolic interactions, however, is at odds with evolutionary theory: why should an organism invest costly resources to benefit other individuals rather than using these metabolites to maximize its own fitness? Recent empirical work has shown that bacterial genotypes can significantly benefit from trading metabolites with other bacteria relative to cells not engaging in such interactions. Here, we will provide a comprehensive overview over the ecological factors and evolutionary mechanisms that have been identified to explain the evolution and maintenance of metabolic mutualisms among microorganisms. Furthermore, we will highlight general principles that underlie the adaptive evolution of interconnected microbial metabolic networks as well as the evolutionary consequences that result for cells living in such communities.

Ronald Noë's insight:
This is a somewhat overwhelming (433 refs!) review of trading among baxcteria and between bacteria and other organisms. Trade doesn't necessarily to markets, but in combination with partner choice, which is also extensively reviewed, one is close enough even if the word 'market' doesn't appear in the text. In any case a rich source for all those struggling to keep up with the recent literature on trade involving bacteria.
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Shu, Zhang, Queller & Strassmann (2018). Burkholderia bacteria use chemotaxis to find social amoeba Dictyostelium discoideum hosts. The ISME Journal

Shu, Zhang, Queller & Strassmann (2018). Burkholderia bacteria use chemotaxis to find social amoeba Dictyostelium discoideum hosts. The ISME Journal | Biological Markets | Scoop.it

Abstract: A key question in cooperation is how to find the right partners and maintain cooperative relationships. This is especially challenging for horizontally transferred bacterial symbionts where relationships must be repeatedly established anew. In the social amoeba Dictyostelium discoideum farming symbiosis, two species of inedible Burkholderia bacteria (Burkholderia agricolaris and Burkholderia hayleyella) initiate stable associations with naive D. discoideum hosts and cause carriage of additional bacterial species. However, it is not clear how the association between D. discoideum and its carried Burkholderia is formed and maintained. Here, we look at precisely how Burkholderia finds its hosts. We found that both species of Burkholderia clones isolated from D. discoideum, but not other tested Burkholderia species, are attracted to D. discoideum supernatant, showing that the association is not simply the result of haphazard engulfment by the amoebas. The chemotactic responses are affected by both partners. We find evidence that B. hayleyella prefers D. discoideum clones that currently or previously carried Burkholderia, while B. agricolaris does not show this preference. However, we find no evidence of Burkholderia preference for their own host clone or for other hosts of their own species. We further investigate the chemical differences of D. discoideum supernatants that might explain the patterns shown above using a mass spectrometry based metabolomics approach. These results show that these bacterial symbionts are able to preferentially find and to some extent choose their unicellular partners. In addition, this study also suggests that bacteria can actively search for and target phagocytic cells, which may help us better understand how bacteria interact with immune systems.

Ronald Noë's insight:
This is not really about tiny markets, but shows that bacteria can exert partner choice very well. The amoeba of this paper are known for their habit of 'farming' bacteria. Farming is made possible with the help of the Burkholderia-bacteria, which are not suited as amoebe-food themselves. In this paper the authors show that two species of Burkholderia actively seek out their amoebe-hosts by chemotaxis. This mechansism of partner choice is also know from other mutualistic bacteria, such as the rhizobia (attracted to plant roots where they become N-providers in nodules formed on the roots) and Vibrio that enter the light organs of bobtail squids where they take care of the light production (bioluminiscence) their hosts need as a kind of camouflage.
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Smith, Larroucau, Mabulla & Apicella (2018). Hunter-gatherers maintain assortativity in cooperation despite high-levels of residential change and mixing. bioRxiv

Smith, Larroucau, Mabulla & Apicella (2018). Hunter-gatherers maintain assortativity in cooperation despite high-levels of residential change and mixing. bioRxiv | Biological Markets | Scoop.it

Abstract: Widespread cooperation is a defining feature of human societies from hunter-gatherer bands to nation states. But explaining its evolution remains a challenge. While positive assortment of cooperators with cooperators is recognized as a basic requirement for the evolution of cooperation, the mechanisms governing assortment are debated. Moreover, the social structure of modern hunter-gatherers, characterized by high mobility, residential mixing and low genetic relatedness, undermine assortment and add to the puzzle of how cooperation evolved. Here, we analyze four years of data (2010, 2013, 2014, 2016) tracking residence and levels of cooperation elicited from a public goods game (PG), in Hadza hunter-gatherers of Tanzania. Data were collected from 56 camps, comprising 383 unique individuals, 137 of whom we have data for two or more years. Despite significant residential mixing, we observe a robust pattern of assortment necessary for cooperation to evolve: In every year, Hadza camps exhibit high between-camp and low within-camp variation in cooperation. We further consider the role of homophily in generating this assortment. We find little evidence that cooperative behavior within individuals is stable over time or that similarity in cooperation between dyads predicts their future cohabitation. Both sets of findings are inconsistent with homophilic models that assume stable cooperative and selfish types (e.g. partner choice). Consistent with social norms, culture and reciprocity theories, the data suggest that the strongest predictor of an individual's level of cooperation in any given year is the mean cooperation of their campmates in that year. These findings underscore the adaptive nature of human cooperation - particularly its responsiveness to social contexts - as a feature important in generating the assortment necessary for cooperation to evolve.


Keywords: evolution of cooperation, homophily, partner choice, social influence, social norms, hunter-gatherers

Ronald Noë's insight:
The authors measured the tendency of Hadza hunter-gatherers from northern Tanzania to form groups living together in camps on the basis of cooperativeness. I listed this paper here, because it tests ‘partner choice models’, among others, and refers to BMT as one of those. The tendency of to cooperate is measured as an individual’s contribution in a public goods game (PGG) over several years. The authors neither find assortment on the basis of average contributions in the PGG (‘homophily’), nor a tendency to move to camps with generous contributors or to stay with the latter. They interpret this as lack of support for partner choice models.
I am not sure that I indeed recognise BMT as a model tested here. BMT is about dyadic cooperation and I am not convinced an n-player game tests the tendency to cooperate in a two-player situation very well. BMT also doesn’t predict choice on the basis of cooperativeness as such, but on the basis of profitability as a partner, which also depends on factors such as the partner’s status, skill, knowledge etc.. The authors indeed mention this problem. Moreover, BMT would only predict assortment in the sense measured here, if cooperativeness would be the major factor determining profitability AND competition over partners would force less cooperative ‘choosers’ to settle for less cooperative partners. It is not clear to me, however, that such competition takes place, i.e. that individuals are forced out of groups or that group sizes are strictly limited. In short, I find the paper highly interesting as such, but I am not convinced it reports a valid test of BMT.
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Muggleton, Tarran & Fincher (2018). Who punishes promiscuous women? Both women and women, but only women inflict costly punishment. Evolution and Human Behavior

Muggleton, Tarran & Fincher (2018). Who punishes promiscuous women? Both women and women, but only women inflict costly punishment. Evolution and Human Behavior | Biological Markets | Scoop.it
Abstract: Across human societies, female sexuality is suppressed by gendered double standards, slut shaming, sexist rape laws, and honour killings. The question of what motivates societies to punish promiscuous women, however, has been contested. Although some have argued that men suppress female sexuality to increase paternity certainty, others maintain that this is an example of intrasexual competition. Here we show that both sexes are averse to overt displays of female sexuality, but that motivation is sex-specific. In all studies, participants played an economic game with a female partner whose photograph either signalled that she was sexually-accessible or sexually-restricted. In study 1, we found that men and women are less altruistic in a Dictator Game (DG) when partnered with a woman signalling sexual-accessibility. Both sexes were less trusting of sexually-accessible women in a Trust Game (TG) (study 2); women (but not men), however, inflicted costly punishment on a sexually-accessible woman in an Ultimatum Game (UG) (study 3). Our results demonstrate that both sexes are averse to overt sexuality in women, whilst highlighting potential differences in motivation.

Keywords: Sexual suppression Sexist attitudes Intrasexual competition Evolutionary psychology Economic games
Ronald Noë's insight:
This is an interesting paper, but has one of the weirdest typos in the title that I have ever seen. Let's assume that "Both men and women.." is meant (or the other way around) and that this will be corrected in the final version.

The authors invoke BMT in the form introduced in this context by Baumeister and colleagues: the form and severity of sexual suppression depends on the state of the mating market and is a way of rigging the market in one's advantage.

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Cossins (2018). The animal economists that can wheel and deal as well as any human. New Scientist Christmas issue (online version)

Cossins (2018). The animal economists that can wheel and deal as well as any human. New Scientist Christmas issue (online version) | Biological Markets | Scoop.it

From monkey markets to fishy business, we’re finding that many animals make rational trades. Even brainless fungi have a thing or two to teach us.

Ronald Noë's insight:
A nice story by Daniel Cossins in the Christmas issue of New Scientist. He notably stresses the fact that one doesn't need a big brain - or any brain at all - to use sophisticated trading strategies.

Note that the same story appeared in print on the 21st of December under the title "Rogue traders"
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Sánchez-Amaro, Duguid, Call & Tomasello (2018). Chimpanzees’ understanding of social leverage. PLOS ONE, 13(12), e0207868

Sánchez-Amaro, Duguid, Call & Tomasello (2018). Chimpanzees’ understanding of social leverage. PLOS ONE, 13(12), e0207868 | Biological Markets | Scoop.it

Abstract: Social primates can influence others through the control of resources. For instance, dominant male chimpanzees might allow subordinates access to mate with females in exchange for social support. However, little is known about how chimpanzees strategically use a position of leverage to maximize their own benefits. We address this question by presenting dyads of captive chimpanzee (N = 6) with a task resulting in an unequal reward distribution. To gain the higher reward each individual should wait for their partner to act. In addition, one participant had leverage: access to an alternative secure reward. By varying the presence and value of the leverage we tested whether individuals used it strategically (e.g. by waiting longer for partners to act when they had leverage in the form of alternatives). Additionally, non-social controls served to show if chimpanzees understood the social dilemma. We measured the likelihood to choose the leverage and their latencies to act. The final decision made by the chimpanzees did not differ as a function of condition (test versus non-social control) or the value of the leverage, but they did wait longer to act when the leverage was smaller—particularly in test (versus non-social control) trials suggesting that they understood the conflict of interest involved. The chimpanzees thus recognized the existence of social leverage, but did not use it strategically to maximize their rewards.

Ronald Noë's insight:
The authors ask a question that is also of interest in the context of BMT: do agents understand that they have leverage over theior partners thanks to outside options they have but their partners don't. Even though the typical outside option that is of interest in most biological markets is having alternative partners to choose from, non-social outside options (e.g. an abiotic source of the resource of interest at hand) should also have an effect. Alejandro Sanchez-Amara and colleagues set up an experiment of the latter kind: one chimpanzee had a non-social outside option, while the other didn't.

This is an interesting experiment, even though providing a social outside option yields - to my mind at least - a more relevant and more interesting experiment (see for an example from the same lab: Melis, Hare & Tomasello (2006). Chimpanzees recruit the best collaborators. Science, 311(5765), 1297-1300).

What I don't quite see is that understanding the fact that one has leverage and hence can use it is such a congitive challenge. In most cases the agent will learn by simple trial-and-error that their conspecifics are willing to pay more or demand less than in situations in which the outside options lack. Wasps, for example , can do that too (Grinsted  & Field (2017). Market forces influence helping behaviour in cooperatively breeding paper wasps. Nature Communications, 8, 13750). In the vervet example cited in the paper (Fruteau et al 2009 PNAS) we didn't assume that the task was cognitive demanding for the female. On the contrarey, the real problem was for those that had to learn to wait to approach the baited food container (Fruteau, van Damme & Noë (2013). Vervet monkeys solve a multiplayer “Forbidden Circle Game” by queuing to learn restraint. Current Biology, 23(8), 665-670).
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Herrmann, Engelmann & Tomasello (2019). Children engage in competitive altruism. Journal of Experimental Child Psychology, 179, 176-189

Herrmann, Engelmann & Tomasello (2019). Children engage in competitive altruism. Journal of Experimental Child Psychology, 179, 176-189 | Biological Markets | Scoop.it
Abstract: Humans cultivate their reputations as good cooperators, sometimes even competing with group mates, to appear most cooperative to individuals during the process of selecting partners. To investigate the ontogenetic origins of such “competitive altruism,” we presented 5- and 8-year-old children with a dyadic sharing game in which both children simultaneously decided how many rewards to share with each other. The children were either observed by a third-person peer or not. In addition, the children either knew that one of them would be picked for a subsequent collaborative game or had no such knowledge. We found that by 8 years of age, children were more generous in the sharing game not only when their behavior was observed by a third party but also when it could affect their chances of being chosen for a subsequent game. This is the first demonstration of competitive altruism in young children, and as such it underscores the important role of partner choice (and individual awareness of the process) in encouraging human cooperation from an early age.

Keywords: Competitive altruism Reputation Cooperation Partner choice Dyadic sharing game 5- and 8-year-old children
Ronald Noë's insight:
A borderline case for these pages perhaps, but highly interesting: the ontogeny of strategies in situations in which being chosen as a partner depends on one's reputation and hence strategies to outcompete competitors in this respect.

Also interesting to see that the importance of partner choice in the context of coperation (slowly) gains recognition among psychologists.
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Sparrowe (2018). LMX and welfare trade-off ratios: An evolutionary perspective on leader-member relations. The Leadership Quarterly

Sparrowe (2018). LMX and welfare trade-off ratios: An evolutionary perspective on leader-member relations. The Leadership Quarterly | Biological Markets | Scoop.it
Abstract: A growing stream of theory and research in evolutionary psychology proposes that people mentally represent dyadic relationships through an internal regulatory variable, the “Welfare Tradeoff Ratio.” I introduce welfare tradeoff theory and indicate how it speaks to the problematic distinction between social exchanges and relationship quality in Leader-Member Exchange (LMX) theory and research. I then address issues related to leader-member agreement, LMX development, upward impression management, emotions in leader-member relationships and LMX differentiation from the perspective of welfare tradeoffs. Implications and consideration of measurement also are discussed.
Ronald Noë's insight:
The author makes an interesting connection between the dynamics of leader - follower ('member') relationships and Pat Barclay's brand of biological market theory.
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Ortega Ballesteros (2018). A comparative study of sociality and prosociality in geladas, Theropithecus gelada, and mandrills, Mandrillus Sphinx. (doctoral thesis Madrid)

Ortega Ballesteros (2018). A comparative study of sociality and prosociality in geladas, Theropithecus gelada, and mandrills, Mandrillus Sphinx. (doctoral thesis Madrid) | Biological Markets | Scoop.it
Sociality or group living has evolved independently in many animal taxa, but only in some of them it is based on social bonds between group members that are serviced through the exchange of a variety of social behaviours with multiple partners. This bonded sociality of nonhuman (and human) primates and of a few other taxa stands out for its reliance on prosociality or cooperation between individuals who typically know well one another and who engage in long-term, highly individualized partnerships. The patterns of sociality and prosociality observed in primates reflect trade-offs between several antagonistic but equally welfare- and fitness-enhancing activities and, ultimately, are the outcome of the way the individuals skilfully manage their inevitable conflicts of interest through strategies of aggressive competition, cooperation and post-conflict reconciliation. Contemporary theory on primate sociality and prosociality emphasizes the need for integrating socioecology (i.e., ecological, demographic and social factors), phylogeny (i.e., evolutionary history) and life history (i.e., life history traits) in any account of the proximate and ultimate causes of variation in primate social systems.
Ronald Noë's insight:
Contains a chapter with a test of BMT.
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"Not your typical fish market" by Rebecca Parsons (Georgia Dolphins Ecology Program)

"Not your typical fish market" by Rebecca Parsons (Georgia Dolphins Ecology Program) | Biological Markets | Scoop.it

First par.: Obviously, we here at GDEP have a lot of love for big, charismatic, marine animals. Marine mammals such as orcas and dolphins are known for their intelligence, complex social structure, and beauty. We could go on and on about the interesting facets of cetacean species (and we have), but today we’re taking a moment to appreciate the not-so-glamorous little guys, the unsung heroes of the deep sea.

Ronald Noë's insight:
A popular science-style account of "fish markets"in the sense of BMT. Unfortunately there is one consistent misspelling: Redouan's surname is Bsary, not Bshari
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Mielke, Preis, Samuni, Gogarten, Wittig & Crockford (2018). Flexible decision-making in grooming partner choice in sooty mangabeys and chimpanzees. Royal Society Open Science, 5(7)

Mielke, Preis, Samuni, Gogarten, Wittig & Crockford (2018). Flexible decision-making in grooming partner choice in sooty mangabeys and chimpanzees. Royal Society Open Science, 5(7) | Biological Markets | Scoop.it

Abstract: Living in permanent social groups forces animals to make decisions about when, how and with whom to interact, requiring decisions to be made that integrate multiple sources of information. Changing social environments can influence this decision-making process by constraining choice or altering the likelihood of a positive outcome. Here, we conceptualized grooming as a choice situation where an individual chooses one of a number of potential partners. Studying two wild populations of sympatric primate species, sooty mangabeys ( Cercocebus atys atys ) and western chimpanzees ( Pan troglodytes verus ), we tested what properties of potential partners influenced grooming decisions, including their relative value based on available alternatives and the social relationships of potential partners with bystanders who could observe the outcome of the decision. Across 1529 decision events, multiple partner attributes (e.g. dominance ranks, social relationship quality, reproductive state, partner sex) influenced choice. Individuals preferred to initiate grooming with partners of similar global rank, but this effect was driven by a bias towards partners with a high rank compared to other locally available options. Individuals also avoided grooming partners who had strong social relationships with at least one bystander. Results indicated flexible decision-making in grooming interactions in both species, based on a partner's value given the local social environment. Viewing partner choice as a value-based decision-making process allows researchers to compare how different species solve similar social problems.


Keywaords: grooming bystanders sooty mangabey chimpanzee decision-making

Ronald Noë's insight:
What is really nice about this paper, is that the authors consider the decisions of primates who to groom when and for how long, as a result of a dynamic decision process the outcome of which can be different from day to day and situation to situation. The paper gives the impression that we are finally approaching the end of a long road that started with tit-for-tatting individuals taking always the same kind of decisions based on rigid rules that took a limited number of parameters such as kinship, rank-distance and the (recent) experiences with the same partner into account.
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Thomson, Yuki, Talhelm, Schug, Kito, Ayanian, . . . Visserman (2018). Relational mobility predicts social behaviors in 39 countries and is tied to historical farming and threat. Proceedings of the ...

Thomson, Yuki, Talhelm, Schug, Kito, Ayanian, . . . Visserman (2018). Relational mobility predicts social behaviors in 39 countries and is tied to historical farming and threat. Proceedings of the ... | Biological Markets | Scoop.it

Abstract: Biologists and social scientists have long tried to understand why some societies have more fluid and open interpersonal relationships—differences in relational mobility—and how those differences influence individual behaviors. We measure relational mobility in 39 societies and find that relationships are more stable and hard to form in east Asia, North Africa, and the Middle East, while they are more fluid in the West and Latin America. Results show that relationally mobile cultures tend to have higher interpersonal trust and intimacy. Exploring potential causes, we find greater environmental threats (like disease and warfare) and sedentary farming are associated with lower relational mobility. Our society-level index of relational mobility for 39 societies is a resource for future studies.Biologists and social scientists have long tried to understand why some societies have more fluid and open interpersonal relationships and how those differences influence culture. This study measures relational mobility, a socioecological variable quantifying voluntary (high relational mobility) vs. fixed (low relational mobility) interpersonal relationships. We measure relational mobility in 39 societies and test whether it predicts social behavior. People in societies with higher relational mobility report more proactive interpersonal behaviors (e.g., self-disclosure and social support) and psychological tendencies that help them build and retain relationships (e.g., general trust, intimacy, self-esteem). Finally, we explore ecological factors that could explain relational mobility differences across societies. Relational mobility was lower in societies that practiced settled, interdependent subsistence styles, such as rice farming, and in societies that had stronger ecological and historical threats.


Keywords: relational mobility culture socioecology multicountry interpersonal relationships

Ronald Noë's insight:
The link between this paper and BMT is perhaps not obvious, but recognized by the authors: more relational mobility means more freedom to choose social partners, which translates into a more open and volatile market of relationships.

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Kern & Radford (2018). Experimental evidence for delayed contingent cooperation among wild dwarf mongooses. Proceedings of the National Academy of Sciences (PNAS)

Kern & Radford (2018). Experimental evidence for delayed contingent cooperation among wild dwarf mongooses. Proceedings of the National Academy of Sciences (PNAS) | Biological Markets | Scoop.it

Abstract: Humans frequently trade goods and can track the amount they owe using memories of past exchanges. While nonhuman animals are also known to be capable of trading cooperative acts immediately for one another, more contentious is the possibility that there can be delayed rewards. We use detailed field observations, social-network analyses, and a playback experiment to demonstrate that wild dwarf mongooses provide more grooming to those groupmates who contribute more to sentinel behavior (acting as a raised guard to look out for danger). We therefore provide experimental evidence of delayed contingent cooperation, and cross-commodity exchange, in a wild nonprimate.

Many animals participate in biological markets, with strong evidence existing for immediate cooperative trades. In particular, grooming is often exchanged for itself or other commodities, such as coalitionary support or access to food and mates. More contentious is the possibility that nonhuman animals can rely on memories of recent events, providing contingent cooperation even when there is a temporal delay between two cooperative acts. Here we provide experimental evidence of delayed cross-commodity grooming exchange in wild dwarf mongooses ( Helogale parvula ). First, we use natural observations and social-network analyses to demonstrate a positive link between grooming and sentinel behavior (acting as a raised guard). Group members who contributed more to sentinel behavior received more grooming and had a better social-network position. We then used a field-based playback experiment to test a causal link between contributions to sentinel behavior and grooming received later in the day. During 3-h trial sessions, the perceived sentinel contributions of a focal individual were either up-regulated (playback of its surveillance calls, which are given naturally during sentinel bouts) or unmanipulated (playback of its foraging close calls as a control). On returning to the sleeping refuge at the end of the day, focal individuals received more grooming following surveillance-call playback than control-call playback and more grooming than a matched individual whose sentinel contributions were not up-regulated. We believe our study therefore provides experimental evidence of delayed contingent cooperation in a wild nonprimate species.


Keywords: biological markets delayed rewards economic behavior reciprocity social information

Ronald Noë's insight:
The authors report both observational data and the results of a beautiful experiment showing that dwarf mongooses reward group members with grooming before going to bed for their sentinel duties during the day. Sentinel behaviour is typical for social mongooses: one or two animals stand on a higher position and look out for the raptors that are ready to attack any time. Sentinels advertise their work with a special call and their group members regularly check the presence of sentinels. The 'sentinel call' is what is used in this study: by using playbacks one can suggest additional duties of an individual that is in fact quietly going about in his daily business.

Compared to primates, with whom a number of more or less comparable studies have been done, the dwarf mongooses have a number of advantages: (1) one can more easily work with multiple groups (here 12 groups in total; playback trials done in 5), (2) doing sentinel duty is a public good that benefits all group members equally and (3) sentinel behaviour is shown during the day, while the grooming is done in the evening at the den, so quite a bit of time may pass between service and reward.

All together the result show that the market value of diligent sentinels increases. All group members are inclined to reward them and not only the dominants or their best friends or their close kin. Worth reading!
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Freitas, DeScioli, Thomas & Pinker (2018). Maimonides’ ladder: States of mutual knowledge and the perception of charitability. Dept. Psychology, Harvard, Dept Political Science, Stony Brook (draft)

Freitas, DeScioli, Thomas & Pinker (2018). Maimonides’ ladder: States of mutual knowledge and the perception of charitability. Dept. Psychology, Harvard, Dept Political Science, Stony Brook (draft) | Biological Markets | Scoop.it
Abstract: Why do people esteem anonymous charitable giving? We connect normative theories of charitability (captured in Maimonides’ Ladder of Charity) with evolutionary theories of partner choice to test predictions on how attributions of charitability are affected by states of knowledge: whether the identity of the donor or of the beneficiary is revealed to the other. Consistent with the theories, in Experiments 1-2 participants judged a double-blind gift as more charitable than one to a revealed beneficiary, which in turn was judged as more charitable than one from a revealed donor. We also found one exception: Participants judged a donor who revealed only himself as slightly less, rather than more, charitable than one who revealed both identities. Experiment 3 explains the exception as a reaction to the donor’s perceived sense of superiority and disinterest in a social relationship. Experiment 4 found that donors were judged as more charitable when the gift was shared knowledge (each aware of the other’s identity, but unsure of the other’s awareness) than when it was common knowledge (awareness of awareness). Experiment 5, which titrated anonymity against donation size, found that not even a hundredfold larger gift could compensate for the disapproval elicited by a donor revealing his identity. Experiments 6-7 showed that participants’ judgments of charitability flip depending on whose perspective they take: observers disapprove of donations that they would make as donors and would prefer as beneficiaries. Together, these experiments provide insight into why people care about how a donor gives, not just how much.

Keywords: Charity; partner choice; reciprocity; common knowledge
Ronald Noë's insight:
This draft paper departs from the idea that people choose their partners on a market of potential candidates, based on the information they have of the latters' cooperative and altruistic behaviour. But what is the criterion for preferring one person over another? This depends on the chooser's estimates of the motives for altruism, but also on knowledge of the relationship between donor and receiver and so forth.

The authors use a classification proposed by the 12th century philosopher Maimonides as inspiration for a series of experiments in which they manipulated the various relevant parameters. The result is a rather long paper that I will soon read in more detail.
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Geoffroy, Baumard & André (2018). Why cooperation is not running away. bioRxiv

Geoffroy, Baumard & André (2018). Why cooperation is not running away. bioRxiv | Biological Markets | Scoop.it

Abstract: A growing number of experimental and theoretical studies show the importance of partner choice as a mechanism to promote the evolution of cooperation, especially in humans. In this paper, we focus on the question of the precise quantitative level of cooperation that should evolve under this mechanism. Using a classic adaptive dynamics model, we first highlight the existence of a paradox. When individuals compete to be chosen by others, their level of investment in cooperation evolves towards ever-higher values, a process called competitive altruism, or runaway cooperation. Our model shows that this runaway process leads to a profitless escalation of the level of cooperation, up to the point where the cost of cooperation exactly cancels out its benefit. In other words, at first sight, under the effect of partner choice we predict that cooperation should have no benefit at ESS. Second, importing models from matching theory in economics we, however, show that, when individuals can plastically modulate their choosiness in function of their own cooperation level, partner choice stops being a runaway competition to outbid others, and becomes a competition to form the most optimal partnerships. Assortative partner choice then leads to the evolution of the socially optimum level of cooperation. This result could explain the observation that human cooperation seems to be often constrained by considerations of social efficiency.


Keywords: partner choice, biological markets, matching models, competitive altruism, human cooperation

Ronald Noë's insight:
This what looks like – to me at least – a very elegant model of the effects of partner choice and the levels of cooperative investment on the evolution of cooperation. The work builds on an extensive number of previous theoretical studies of the same problem, notably those of McNamara etal 2008 and previous work of the same group (Debove, André & Baumard), as well as ‘search and matching’ models from economics

The authors obviously had human cooperation in mind, but their results are much more general than that and could apply to many more intra- and inter-specific biological markets. The authors do not simply try to explain whether cooperation can emerge and remain stable as such, but notably at what level of investment in choosiness and cooperation it should stabilise. With the help of a first model they show the risk of runaway processes that end up in such a high investment in partner choice that the costs are no longer compensated by the benefits of cooperation. This problem will look familiar to those who remember the early days of sexual selection models.
They then introduce a more elaborate model in which the level of choosiness is coupled to the level of cooperative investment, which shows phenotypic variation. In this model assortative matching occurs whereby partners match each other in the level of investment and the runaway problem disappears.
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