Partner Preference Research Articles

EGFR in Cancer: Signaling Mechanisms, Drugs, and Acquired Resistance.

Simple SummaryGrowth factors are hormone-like molecules able to promote division and migration of normal cells, but cancer captured the underlying mechanisms to unleash tumor growth and metastasis. Here we review the epidermal growth factor (EGF), which controls epithelial cells, the precursors of all carcinomas, and the cognate cell surface receptor, called EGFR. In addition to over-production of EGF and its family members in tumors, EGFR is similarly over-produced, and mutant hyper-active forms of EGFR are uniquely found in some brain, lung, and other cancers. After describing the biochemical mechanisms underlying the cancer-promoting actions of EGFR, we review some of the latest research discoveries and list all anti-cancer drugs specifically designed to block the EGFR’s biochemical pathway. We conclude by explaining why some patients with lung or colorectal cancer do not respond to the anti-EGFR therapies and why still other patients, who initially respond, become tolerant to the drugs.The epidermal growth factor receptor (EGFR) has served as the founding member of the large family of growth factor receptors harboring intrinsic tyrosine kinase function. High abundance of EGFR and large internal deletions are frequently observed in brain tumors, whereas point mutations and small insertions within the kinase domain are common in lung cancer. For these reasons EGFR and its preferred heterodimer partner, HER2/ERBB2, became popular targets of anti-cancer therapies. Nevertheless, EGFR research keeps revealing unexpected observations, which are reviewed herein. Once activated by a ligand, EGFR initiates a time-dependent series of molecular switches comprising downregulation of a large cohort of microRNAs, up-regulation of newly synthesized mRNAs, and covalent protein modifications, collectively controlling phenotype-determining genes. In addition to microRNAs, long non-coding RNAs and circular RNAs play critical roles in EGFR signaling. Along with driver mutations, EGFR drives metastasis in many ways. Paracrine loops comprising tumor and stromal cells enable EGFR to fuel invasion across tissue barriers, survival of clusters of circulating tumor cells, as well as colonization of distant organs. We conclude by listing all clinically approved anti-cancer drugs targeting either EGFR or HER2. Because emergence of drug resistance is nearly inevitable, we discuss the major evasion mechanisms.

Making Choices in Discourse: New Alternative Masculinities Opposing the “Warrior’s Rest”

Psychology research on men studies, attractiveness, and partner preferences has evolved from the influence of sociobiological perspectives to the role of interactions in shaping election toward sexual–affective relationships and desire toward different kinds of masculinities. However, there is a scientific gap in how language and communicative acts among women influence the kind of partner they feel attracted to and in the reproduction of relationship double standards, like the myth of the “warrior’s rest” where female attractiveness to “bad boys” is encouraged or supported. Some women imitate “the warrior” behavior of men by choosing dominant traditional masculinities (DTM) to have “fun” with and oppressed traditional masculinities (OTM) for “rest” after the “fun” with DTM—choosing an OTM for a stable relationship, but perhaps without passion, while also feeling attraction toward DTM, a response which perpetuates the chauvinist double standard that the feminist movement has condemned when men behave in this sexist way. Through conducting a qualitative study with communicative daily life stories, this article explores, on the one hand, how language and social interaction among women can lead to the reproduction of the DTM role by women and, on the other hand, also how new alternative masculinities (NAM) offer an alternative by explicitly rejecting, through the language of desire, to be the rest for the female warrior, the second fiddle to any woman. This has the potential to become a highly attractive alternative to DTM. Findings provide new knowledge through the analysis of communicative acts and masculinities evidencing the importance of language uses in the reproduction of the double standards in gender relations and to understand how and why these practices are maintained and which kind of language uses can contribute to preventing them. Implications for research and interventions on preventive socialization of gender violence are discussed.

A Comparative Analysis of Risky Sexual Behaviors, Self-Reported Sexually Transmitted Infections, Knowledge of Symptoms and Partner Notification Practices among Male and Female University Students in Pretoria, South Africa.

The surge of sexually transmitted infections (STIs) among young people is of public health importance, and the notification and treatment of sex partners after the diagnosis of an STI is a public health approach to prevent and reduce further transmissions. There are limited studies that investigate partner notification among young people in general, and university students in South Africa in particular. We investigated self-reported STIs and partner notification practice, intentions, and preferences among university students. We also assessed their STI knowledge and risky sexual behaviour in relation to STIs. The study was a descriptive cross-sectional survey that used multistage sampling to select 918 students across the five schools of a health sciences university in South Africa. Descriptive statistics and bivariate logistic analysis were performed using Stata IC version 16. More males (54.1%) than females were currently in a sexual relationship (47.3%), more males reported multiple sexual partners (n = 114, 46%), engaged in transactional sex (n = 13, 5.3%), and had one-night stands (n = 68, 28.1%) in the past 12 months (p = 0.001). Moreover, half (55.9%) had poor knowledge of STIs with an overall mean knowledge score of 2.9 ± 2.0, and the majority (85.8%) perceived themselves to be at low risk of acquiring STIs. The odds of intentions to disclose an STI infection to a sexual partner and delivering a partner notification slip to ex-sexual partners were not statistically significant (p = 0.95; p = 0.10), with the likelihood of disclosure being 1.3 times for female students compared to males. Female students were 1.5 times as likely to prefer a doctor to send an SMS notification to their sexual partners (p = 0.02) compared to their male counterparts, while the preference of an SMS notification was 41% (p = 0.03) among female students. Students engaged in risky behaviours but had a low perception of the risks of acquiring STIs. Although they had preferences of different methods of partner notification, both male and female students preferred SMS partner notifications from a doctor, even though women were in the majority. Health care providers should put in place interventions so that young people can safely inform their partners about STIs.

Social autonomy ≠ social empowerment: The social self‐restriction model

This paper introduces the social self-restriction (SSR) model, which highlights a drawback associated with the increasingly accessible privilege of social autonomy. Social autonomy enables individuals to connect with preferred social partners and avoid undesirable others. The benefits of social autonomy are undeniable; however, the SSR model makes the novel assertion that people tend to exercise social autonomy in ways that ultimately constrain their potential for social empowerment—a higher-order form of personal freedom. Attaining the ideal of high social empowerment requires both high social autonomy and high social adaptability. People with high social adaptability can feel reasonably comfortable and act competently in social environments they did not choose to inhabit. Unfortunately, people with high social autonomy are unlikely to possess high social adaptability. We propose that social autonomy undermines social adaptability by tempting people to avoid social challenges and socialize selectively with similar others in familiar contexts, a habit that limits social skill development, promotes social intolerance, and distorts social perceptions. In essence, we argue that social autonomy allows people to live in their social comfort zones, at the cost of restricting their social range. Our discussion of the SSR model incorporates evidence and perspectives from a broad range of academic disciplines, and includes consideration of opportunities for future research.

Mirvetuximab soravtansine, a folate receptor alpha (FRα)-targeting antibody-drug conjugate (ADC), in combination with bevacizumab in patients (pts) with platinum-agnostic ovarian cancer: Final analysis.

5504 Background: Mirvetuximab soravtansine (MIRV) is an ADC comprising a FRα-binding antibody, cleavable linker, and the maytansinoid DM4, a potent tubulin-targeting agent. As part of the Phase 1b FORWARD II trial (NCT02606305), the combination of MIRV with bevacizumab (BEV) was evaluated in pts with FRα-positive (medium/high expression; ≥50%/ ≥75% of cells with PS2+ staining intensity), platinum agnostic ovarian cancer, defined as pts with either platinum resistant (PROC) (recurrence within 6 months after last platinum dose) or platinum sensitive (PSOC)responded to the last platinum therapy and did not progress within 6 months) for whom a non-platinum based doublet would be appropriate. Methods: Pts received MIRV (6 mg/kg; adjusted ideal body weight) and BEV (15 mg/kg) on Day 1 of a 21-day cycle. Responses were assessed by investigator according to RECIST 1.1 and adverse events (AEs) evaluated by CTCAE v4.03. Results: In total, 60 pts received the combination, with a median age of 60 years, a median of 2 prior lines of systemic therapy (range 1-4) and a median follow-up of 17.5 months. The cohort included 32 pts (53%) with PROC disease and 28 (47%) with PSOC disease. Objective responses were seen in 28 of 60 pts for a confirmed overall response rate (ORR) of 47% (95% CI, 34, 60), median duration of response (mDOR) of 9.7 months (95% CI 6.7, 12.9), and median progression free survival (mPFS) of 8.3 months (95% CI 5.6, 10.6). In pts with high FRα expression (n=33), the confirmed ORR was 64% (95% CI 45, 80), mDOR of 11.8 months (95% CI 6.7, 13.7), and mPFS of 10.6 months (95% CI 8.3, 13.3); efficacy results in PROC and PSOC subsets of pts with high FRα expression are shown in the table below. The most common treatment related AEs (all grade, grade 3+) were diarrhea (68%, 2%), blurred vision (63%, 2%), fatigue (58%, 7%), and nausea (57%, 0%). The most common treatment related grade 3 and 4 AEs were neutropenia and hypertension, (12%, 3% and 13%, 0%, respectively); all other grade 3+ events occurred in ≤ 10% of pts. Conclusions: The combination of MIRV with BEV demonstrates impressive anti-tumor activity with durable responses and favorable tolerability in high FRα recurrent ovarian cancer. These results build on data previously reported for MIRV/BEV in PROC patients ( Gyn Oncology O’Malley, et al 2020), suggesting that MIRV has the potential to be a preferred partner for BEV in patients with high FRα recurrent ovarian cancer regardless of platinum sensitivity. Clinical trial information: NCT02606305. [Table: see text]

Almost mutually best in matching markets: rank gaps and size of the core

This paper studies the one-to-one two-sided marriage model (Gale and Shapley 1962). If agents’ preferences exhibit mutually best (i.e., each agent is most preferred by her/his most preferred matching partner), there is a unique stable matching without rank gaps (i.e., in each matched pair the agents assign one another the same rank). We study in how far this result is robust for matching markets that are “close” to mutually best. Without a restriction on preference profiles, we find that natural “distances” to mutually best neither bound the size of the core nor the rank gaps at stable matchings. However, for matching markets that satisfy horizontal heterogeneity, “local” distances to mutually best provide bounds for the size of the core and the rank gaps at stable matchings.

Leveraging the balanced scorecard – a tool for SME advancement

Learning outcomes Illustrate the typical organizational responsibility of a small, medium industry dealing with precision manufacturing products. Introduce a balanced scorecard (BSC) as a concept about the case in the context. Introduce the parameters specific to small and medium enterprise (SME) that could be considered to be part of the key performance indicators. Understand the advantages and disadvantages of using a BSC in SMEs in emerging economies. Case overview/ synopsis Gopika Rani, the recently hired Executive Assistant along with Sanjana M, the Business Development Manager of SEP India Private Ltd. (SEPI), a small medium enterprise, were finalizing a proposal for the forthcoming “India Small Business Excellence Awards 2020.” The proposal was to be considered by the Board of Directors scheduled to meet next week for approvals. Sanjana apprises Gopika on CRISIL’s policy advisory role and its annual awards scheme for SMEs in India. She also details recent modifications announced by the Government of India that had impacted SEPI and was pertinent for filling the application. Gopika understood that SEPI was well-known for the precision and durability of its component, and was poised for growth. The business catered to global suppliers (Tier-1 companies) of the Indian automotive industry that accounted for over 75% and the balance contributed to exports. SEPI’s unique products such as Starter Motor Ignition or the Fuel Vending pump (Automotive) or the non-automotive products such as arrowheads and bowstrings (sports) or the heart-valves (medical) have all the quality certifications. For new product development, customer feedback played a crucial role at all stages of development from prototype to pilot tests. SEPI’s mission “be our customers’ preferred supplier and business partner” drove their personnel and organizational objectives. Also, SEPI could get multiple benefits and be in a strong market position because of this award recognition. Gopika was, however, unclear about SEPI’s business strategies and use of appropriate performance measurement tools. Gopika desired to address the Board of Directors next week on her idea of applying a BSC as a useful “strategic planning and management tool.” The BSC methodology can be used to monitor the performance of SME firms against strategic goals. It can be successfully implemented in smaller organizations because of their simpler set-ups and tendency to arrive at a consensus quickly. However, implementation of BSC within the Indian micro, small and medium enterprises has been scant. Several studies found that the lack of ownership, resistance to change, a scarcity of training and coordination between the departments and lack of funds were among the challenges. The firms also had to make numerous changes to their strategies as business environments evolved. Gopika was convinced that the tool could blend in all the “four perspectives – customer, financial, internal business and learning and growth” and grow. The tool could demonstrate meeting all the prerequisites, “needs to have an exemplary vision, demonstrate outstanding business acumen, use best practices and create a legacy for the others to follow,” that were prerequisites for receipt of this award. Her next project would be to seek approval for the implementation of BSC, a beneficial and apt tool for SEPI. Do you agree with Gopika Rani that BSC is a suitable tool for SEPI? If yes, why? If no, why? Complexity academic level This case study titled leveraging the BSC – a tool for SME advancement is intended for use in the graduate management program (MBA) in subject electives, namely, entrepreneurship, strategy formulation, human resource management or production management. Supplementary materials Teaching Notes are available for educators only. Subject code CSS 3: Entrepreneurship. Supplementary materials Teaching Notes are available for educators only.

Reduced sexual motivation of diabetic female rats: Restoration with insulin

The aim of this study was to evaluate female rat sexual motivation in a model of diabetes mellitus type 1. Severe hyperglycemia was induced in ovariectomized Wistar rats by injecting streptozotocin [STZ, 100 mg/kg, i.p.]. Ten days later, females received estradiol benzoate (10 μg/rat, s.c.) plus progesterone (3 mg/rat, s.c.). A group of STZ-treated animals was administered with insulin (2–4 U) every 12 h for 10 days, which normalized glucose levels. In the partner preference (PP) and sexual incentive motivation (SIM) tests, control females spent more time close to a sexually experienced male (SE) than with a castrated male (CM). STZ-treated females stayed the same amount of time with both stimuli, that is, they lost their sexual preference. We also evaluated the sense of smell using two behavioral tests, one related to sexual odors (SO) and another one to food odors (FO). In the SO test, control females spent more time sniffing the sawdust coming from cages that contained SE males; hyperglycemic females remained the same amount of time sniffing the sawdust of both stimuli: SE and CM. In the FO test, no differences were found between control and STZ-treated groups. Insulin treatment reverted the changes observed in hyperglycemic females in the PP, SIM and SO tests. These data suggest that severe hyperglycemia decreases sexual motivation and that insulin recovers such diminution.

Dark triad, sociosexual orientation, and mate preferences in short and long-term relationships – Exploratory study

Some partner preferences are universal, while others show a pronounced inter-individual variation. As both Dark Triad and sociosexuality play an important role in mate choice, this study measured how inter-individual variation in these traits relate to preferred mate characteristics over two mating conditions. Participants (N = 419, M age = 20.62, SD = 4.27) completed an on-line survey on mate preferences, short Dark Triad measure, and sociosexuality inventory (SOI Attitude, Behaviour and Desire). Narcissism in women correlated with most demands (e.g., good financial prospects) in both short and long-term relationships. Machiavellianism in women correlated with preferring long and short-term partners with financial prospects, and short-term partners with favourable social status. Psychopathy in women had a negative association with several preferences (e.g., desire for children), but only in long-term context. The only significant correlation in men was between narcissism and preference for favourable social status in long-term partners. In both sexes and across both mating contexts chastity correlated negatively with sociosexual attitude. We also found a number of significant, negative correlations between sociosexual attitude and mate preferences in women (e.g., similar religion, desire for children).

Settling down without settling: Perceived changes in partner preferences in response to COVID-19

The goal of this study was to explore the positive association between concern related to COVID-19 and single individuals’ perceived changes to their partner preferences. In addition, we investigated the mediating role of fear of being single. Results indicated that people with greater COVID-19 concern perceived an increase in the importance of stability, family commitment, and physical/social attractiveness, as well as fear of being single. Fear of being single only negatively predicted the importance of physical/social attractiveness, whereas it positively predicted the importance of stability and family commitment. Thus, in most cases, people with a greater concern for COVID-19 perceived themselves to become more selective, even when they exhibit higher levels of fear of being single.

Prenatal Androgen Excess Impairs Sexual Behavior in Adult Female Mice: Perspective on Sexual Dysfunction in PCOS

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders worldwide, affecting 5-20% of reproductive aged women [1]. PCOS is characterised by androgen excess, oligo- or anovulation, and polycystic ovarian morphology [1]. PCOS patients also experience sexual dysfunction, including decreased sexual desire, increased sexual dissatisfaction and gender dysphoria [2-4]. The origins of PCOS-related sexual difficulties remain unidentified, but may be related to impaired central mechanisms regulating sexual behaviours. Prenatally androgenized (PNA) mice recapitulate the PCOS phenotype and exhibit alterations in the neuronal network regulating reproductive function [5], providing a powerful, pathology-based model to unravel the biological origins of sexual dysfunction in PCOS. Here, we aimed to determine whether female sexual behaviours are impaired in the PNA mouse model of PCOS. To model PCOS, female dams received injections of dihydrotestosterone (PNA) or oil vehicle (VEH) daily from gestational day 16-18. Adult female offspring were ovariectomized and implanted with a silastic capsule of estradiol to examine the female-typical sexual behaviour: lordosis as well as partner preference. We also examined a potential masculinisation of the brain by replacing the estradiol implant by a testosterone implant then testing the female for male-like sexual behaviours. PNA females exhibited significantly reduced lordosis behaviour compared to VEH females (p<0.01). In contrast, partner preference and male-like sexual behaviour were not different between PNA and VEH females. In addition, using Open-field test and elevated-plus maze, we observed no effect of prenatal androgen exposure on locomotion and anxiety. These results highlight, for the first time, that prenatal exposure to the non-aromatisable androgen, DHT, impairs female receptivity only without masculinisation. These findings support the use of the PNA mouse model of PCOS to identify the neuronal targets of prenatal androgen action and to determine the mechanisms by which prenatal androgen excess impairs lordosis. Taken together, this study introduce a novel perspective on the origins of sexual dysfunction in women with PCOS and indicate the need for further investigation into the mechanisms of androgen excess on the female brain and sexual function. [1] Lizneva D et al, Fertil Steril. 2016;106:6-15. [2] Fliegner M et al, Geburtshilfe Frauenheilkd. 2019;79:498-509.[3] Kowalczyk R et al, Acta Obstet Gynecol Scand. 2012;91:710-4.[4] Mansson M et al, Eur J Obstet Gynecol Reprod Biol. 2011;155:161-5. [5] Ruddenklau A, Campbell RE. Endocrinology. 2019 Oct 1;160(10):2230-2242.

Strongly bonded individuals prefer to forage together in cooperatively breeding dwarf mongoose groups

In many social species, group members form strong social bonds. Such strong bonds are well-known to generate long-term fitness benefits, but they are also expected to influence short-term behavioural decisions. Here, we use field observations and an experimental manipulation to investigate whether variation in social-bond strength (as determined from grooming interactions) influences nearest-neighbour choices while foraging in wild dwarf mongooses (Helogale parvula). Preferred grooming partnerships (PGPs), representing particularly strong bonds, were found predominately between male–female dyads but among a range of dominance-status dyads. When searching for food, dwarf mongooses with PGPs were more likely than expected by chance to forage close to a preferred grooming partner. Foraging near a strongly bonded groupmate might reduce the predation risk or increase foraging opportunities and the transfer of social information. In addition, there could be stress-reducing benefits, although our field experiment provided no evidence that nearest-neighbour preferences for strongly bonded groupmates were additionally favoured, or indeed disrupted, in the aftermath of a short-term stressful event. Investigating the potential influence of strong social bonds on short-term behavioural decisions with potential fitness consequences is important for our understanding of social interactions and cooperation. Enduring, close social bonds between individuals provide considerable long-term health and fitness benefits, but are also expected to influence short-term behavioural decisions. We investigated whether social-bond strength (as determined from grooming interactions) influenced foraging decisions in cooperatively breeding dwarf mongoose groups. We found particularly strong social bonds in the form of preferred grooming partnerships in a subset of male–female dyads. Dwarf mongoose foraging decisions were affected by the strength of their social relationships with groupmates: individuals with preferred grooming partners preferred to have these individuals as their nearest neighbours when searching for food. We used a field-based experimental manipulation to investigate whether stressful events impact nearest-neighbour choices, but found no evidence that preferences to forage near strongly bonded groupmates were disrupted or more additionally favoured in the aftermath of a stressful event. Our current work extends understanding of how social bonds can potentially influence within-group behaviour.

Matching for Strategic Organizations: Theory and Empirics from Internal Labor Markets

Organizations have recently embraced the tools of market design to address job assignment and internal mobility problems. However, matching objectives within an organization are distinct from those in other settings. We model firm-optimal job assignments and the tradeoffs of using different matching institutions. Our results illuminate where preference-respecting mechanisms (such as those developed for stable matching) perform well for organizational purposes. We then turn to a large organization's internal labor market for empirics. We find that optimal matching is highly productive. Using the organization's preferred metric, the optimal match is 36% more productive than randomly assigned matches within job categories. However, it achieves this through negative assortative matching, placing a majority of workers and managers with assignments they did not rank. By contrast, preference-based matches (using deferred acceptance) are much less productive. They are only 3% more valuable to the firm than the average random match, 24% less than the firm's optimal, and feature positive assortative matching. However, workers and managers are significantly more likely to be assigned to a preferred partner; only 25% are assigned to a match they did not rank.

Attraction Preferences of Men who have Sex with Men

The attraction preferences of men who have sex with men (MSM) are largely unknown. While previous research has examined certain aspects tied to masculinity and race, no comprehensive study has been conducted. The current research addressed this gap by conducting two comprehensive surveys of the attraction preferences for MSM participants. The two surveys had participants identify key elements about themselves and then identify the attraction of these same elements in others. The results showed there were no universal ideal preferences for MSMs. That said, we found trends suggesting different body typed individuals have strong preferences for other body types. We discuss the practical implications of these findings, including the potential to predict attraction among the MSM population. This research supports the belief that MSMs have strong preferences for potential sexual partners.

Comparative Assessment of Familiarity/Novelty Preferences in Rodents.

Sociality—i.e., life in social groups—has evolved many times in rodents, and there is considerable variation in the nature of these groups. While many species-typical behaviors have been described in field settings, the use of consistent behavioral assays in the laboratory provides key data for comparisons across species. The preference for interaction with familiar or novel individuals is an important dimension of social behavior. Familiarity preference, in particular, may be associated with more closed, less flexible social groups. The dimension from selectivity to gregariousness has been used as a factor in classification of social group types. Laboratory tests of social choice range from brief (10 minutes) to extended (e.g., 3 hours). As familiarity preferences typically need long testing intervals to manifest, we used 3-hour peer partner preference tests to test for the presence of familiarity preferences in same-sex cage-mates and strangers in rats. We then conducted an aggregated analysis of familiarity preferences across multiple rodent species (adult male and female rats, mice, prairie voles, meadow voles, and female degus) tested with the same protocol. We found a high degree of consistency within species across data sets, supporting the existence of strong, species-typical familiarity preferences in prairie voles and meadow voles, and a lack of familiarity preferences in other species tested. Sociability, or total time spent near conspecifics, was unrelated to selectivity in social preference. These findings provide important background for interpreting the neurobiological mechanisms involved in social behavior in these species.

Effects of sexual imprinting on partner preference for personality traits in Chinese gay men

Sexual imprinting refers to the phenomena where an individual's mate selection behavior is influenced by the characteristics of their parents in the early stages of life. Previous studies revealed that heterosexual men and women prefer partners with personality traits similar to their opposite-sex parents, indicating the sexual imprinting effects in personality preferences. This study aims to examine whether there are sexual imprinting effects on partner preferences for personality traits in gay men. We tested whether parent-child relationship in childhood (before 12 years old) and/or adolescence (12–18 years old) moderated the sexual imprinting effects. Participants (N = 311) were asked to assess their parents' and ideal partner's Big Five personality traits and gender roles, respectively. The parent-child relationships in childhood and adolescence were also assessed. The results revealed that gay men's ideal partner's traits were similar to their fathers' traits for emotional stability, similar to their mothers' traits for agreeableness and openness, and similar to both their fathers' and mothers' traits for conscientiousness. The ideal partners' gender roles were similar to both mothers' and fathers' instrumentality and expressiveness. The relationship quality with the mother in childhood modulated the mating effects in conscientiousness and expressiveness. The relationship quality with the father in adolescence modulated the mating effects in masculine instrumentality. The findings indicated the sexual imprinting effects on partner preference for personality traits in gay men and both father's and mother's personality traits in shaping gay's partner preference.

Emotional bookkeeping and differentiated affiliative relationships: Exploring the role of dynamics and speed in updating relationship quality in the EMO-model.

Emotional bookkeeping is the process by which primates integrate the emotional effects of social interactions to form internal representations of their affiliative relationships. The dynamics and speed of this process, which comprises the formation, maintenance and fading out of affiliative relationships, are not clear. Empirical data suggest that affiliative relationships are slowly formed and do not easily fade out. The EMO-model, an agent-based model designed to simulate the social life of primates capable of emotional bookkeeping, was used to explore the effects of different types of internal relationship dynamics and speeds of increase and decrease of relationship strength. In the original EMO-model the internal dynamics involves a fast built-up of a relationship independent of its current quality, alongside a relatively fast fading out of relationship quality. Here we explore the effect of this original dynamics and an alternative dynamics more in line with empirical data, in combination with different speeds of internal relationship quality increase and decrease, on the differentiation and stability of affiliative relationships. The alternative dynamics leads to more differentiated and stable affiliative relationships than the original dynamics, especially when the speed with which internal relationship quality increases is low and the speed with which it decreases is intermediate. Consequently, individuals can groom different group members with varying frequency and support a rich social life with stable preferred partners and attention to several others. In conclusion, differentiated and stable affiliative relationships are especially formed when friends are not made too quickly and not forgotten too easily.

Performance in video games affects self-perceived mate value and mate preferences.

Mate value is tied to appearance and age in women, and social status and wealth in men. Theory surrounding self-perceived mate value suggests that mate value shows relatively little situational plasticity. Here we challenge this concept by asking participants to compete in video games to test (a) whether self-perceived and actual performance affects subjective mate value, and (b) whether subjective mate value affects mate preferences. By randomly allocating participants to play either a violent or nonviolent game in three separate experiments, we show that both men and women who played a violent game had significantly lower self-perceived performance, and as a result, reported a lower self-perceived mate value. We also demonstrate that this effect led to different preferences for short-term mating partners, mainly among women. Our results strongly suggest that mate value in humans is situationally dynamic and responds to recent contest experiences, as it does in nonhumans. We discuss our results with reference to online multiplayer digital gaming experiences and how variation in self-perceived mate value affects mating market dynamics. (PsycInfo Database Record (c) 2021 APA, all rights reserved) Public Significance Statement—People’s perceptions of their own quality as romantic partners (i.e., their mate value) often depends on physical attractiveness for women or social status for men. Here we show that self-perceived mate value is not a fixed trait but varies according to subjective performance in a competitive video game. Compared with people who played nonviolent video games, the men and women that played a violent video game believed they performed more poorly and rated themselves as having a relatively lower mate value. These experiments provide evidence that people’s perception of their quality as romantic partners varies according to the social experiences they have and their performance in online contests. (PsycInfo Database Record (c) 2021 APA, all rights reserved)

Natural variation in the oxytocin receptor gene and rearing interact to influence reproductive and nonreproductive social behavior and receptor binding

Individual variation in social behavior offers an opportunity to explore gene-by-environment interactions that could contribute to adaptative or atypical behavioral profiles (e.g., autism spectrum disorders). Outbred, socially monogamous prairie voles provide an excellent model to experimentally explore how natural variations in rearing and genetic diversity interact to shape reproductive and nonreproductive social behavior. In this study, we manipulated rearing (biparental versus dam-only), genotyped the intronic NT213739 single nucleotide polymorphism (SNP) of the oxytocin receptor gene (Oxtr), and then assessed how each factor and their interaction related to reciprocal interactions and partner preference in male and female adult prairie voles. We found that C/T subjects reared biparentally formed more robust partner preferences than T/T subjects. In general, dam-only reared animals huddled less with a conspecific in reproductive and nonreproductive contexts, but the effect of rearing was more pronounced in T/T animals. In line with previous literature, C/T animals exhibited higher densities of oxytocin receptor (OXTR) in the striatum (caudoputamen, nucleus accumbens) compared to T/T subjects. There was also a gene-by-rearing interaction in the striatum and insula of females: In the insula, T/T females expressed varying OXTR densities depending on rearing. Overall, this study demonstrates that significant differences in adult reproductive and nonreproductive social behavior and OXTR density can arise due to natural differences in Oxtr, experimental manipulations of rearing, and their interaction.

Cooperative partner choice in multi-level male dolphin alliances

Investigations into cooperative partner choice should consider both potential and realised partners, allowing for the comparison of traits across all those available. Male bottlenose dolphins form persisting multi-level alliances. Second-order alliances of 4–14 males are the core social unit, within which 2–3 males form first-order alliances to sequester females during consortships. We compared social bond strength, relatedness and age similarity of potential and realised partners of individual males in two age periods: (i) adolescence, when second-order alliances are formed from all available associates, and (ii) adulthood, when first-order allies are selected from within second-order alliances. Social bond strength during adolescence predicted second-order alliance membership in adulthood. Moreover, males preferred same-aged or older males as second-order allies. Within second-order alliances, non-mating season social bond strength predicted first-order partner preferences during mating season consortships. Relatedness did not influence partner choice on either alliance level. There is thus a striking resemblance between male dolphins, chimpanzees and humans, where closely bonded non-relatives engage in higher-level, polyadic cooperative acts. To that end, our study extends the scope of taxa in which social bonds rather than kinship explain cooperation, providing the first evidence that such traits might have evolved independently in marine and terrestrial realms.