Cohen, S. E., & Todd, P. M. (2018). Relationship foraging: Does time spent searching predict relationship length? Evolutionary Behavioral Sciences, 12(3), 139-151. http://dx.doi.org/10.1037/ebs0000131
Abstract: Animals foraging for resources often need to alternate between searching for and benefiting from patches of those resources. Here we explore whether such patterns of behavior can usefully be applied to the human search for romantic relationships. Optimal foraging theory (OFT) suggests that foragers should alter their time spent in patches based on how long they typically spend searching between patches. We test whether human relationship search can be described as a foraging task that fits this OFT prediction. By analyzing a large, demographically representative data set on marriage and cohabitation timing using survival analysis, we find that the likelihood of a relationship ending per unit time goes down with increased duration of search before that relationship, in accord with the foraging prediction. We consider the possible applications and limits of a foraging perspective on mate search and suggest further directions for study.
Tuesday, July 10, 2018
Identification of individual subjects on the basis of their brain anatomical features
Identification of individual subjects on the basis of their brain anatomical features. Seyed Abolfazl Valizadeh, Franziskus Liem, Susan Mérillat, Jürgen Hänggi & Lutz Jäncke. Scientific Reports volume 8, Article number: 5611 (2018), https://www.nature.com/articles/s41598-018-23696-6
Abstract: We examined whether it is possible to identify individual subjects on the basis of brain anatomical features. For this, we analyzed a dataset comprising 191 subjects who were scanned three times over a period of two years. Based on FreeSurfer routines, we generated three datasets covering 148 anatomical regions (cortical thickness, area, volume). These three datasets were also combined to a dataset containing all of these three measures. In addition, we used a dataset comprising 11 composite anatomical measures for which we used larger brain regions (11LBR). These datasets were subjected to a linear discriminant analysis (LDA) and a weighted K-nearest neighbors approach (WKNN) to identify single subjects. For this, we randomly chose a data subset (training set) with which we calculated the individual identification. The obtained results were applied to the remaining sample (test data). In general, we obtained excellent identification results (reasonably good results were obtained for 11LBR using WKNN). Using different data manipulation techniques (adding white Gaussian noise to the test data and changing sample sizes) still revealed very good identification results, particularly for the LDA technique. Interestingly, using the small 11LBR dataset also revealed very good results indicating that the human brain is highly individual.
Abstract: We examined whether it is possible to identify individual subjects on the basis of brain anatomical features. For this, we analyzed a dataset comprising 191 subjects who were scanned three times over a period of two years. Based on FreeSurfer routines, we generated three datasets covering 148 anatomical regions (cortical thickness, area, volume). These three datasets were also combined to a dataset containing all of these three measures. In addition, we used a dataset comprising 11 composite anatomical measures for which we used larger brain regions (11LBR). These datasets were subjected to a linear discriminant analysis (LDA) and a weighted K-nearest neighbors approach (WKNN) to identify single subjects. For this, we randomly chose a data subset (training set) with which we calculated the individual identification. The obtained results were applied to the remaining sample (test data). In general, we obtained excellent identification results (reasonably good results were obtained for 11LBR using WKNN). Using different data manipulation techniques (adding white Gaussian noise to the test data and changing sample sizes) still revealed very good identification results, particularly for the LDA technique. Interestingly, using the small 11LBR dataset also revealed very good results indicating that the human brain is highly individual.
Men purchase larger, more expensive engagement rings when imagining themselves mated to a more attractive woman; women desire larger, more expensive engagement rings when imagining themselves mated to a less attractive man
The Effect of Mate Value Discrepancy on Hypothetical Engagement Ring Purchases. Jaime M. Cloud, Madalyn H. Taylor. Evolutionary Psychological Science, https://link.springer.com/article/10.1007/s40806-018-0156-6
Abstract: Few material goods entail as high a cost and carry as little practical value as an engagement ring. Despite their obvious signaling value, engagement ring expenditures have rarely been studied. The purpose of the current study was to experimentally manipulate a discrepancy in the physical attractiveness of romantic partners to determine its effect on hypothetical engagement ring purchases. We predicted that (1) men would purchase larger, more expensive engagement rings when imagining themselves mated to a more attractive rather than less attractive woman and (2) women would desire larger, more expensive engagement rings when imagining themselves mated to a less attractive rather than more attractive man. We further predicted a positive correlation between women’s self-ratings of attractiveness and the size and cost of the engagement ring women chose, regardless of target attractiveness. Results supported all three predictions. Data about the cost and quality of actual engagement rings was also collected to explore their correlations with age and attractiveness discrepancies in real-world couples; however, we failed to find a consistent pattern whereby more desirable women received more expensive and higher quality engagement rings. Results from the experimental portion of the current study show that men invest greater resources in attractive women and that increased resource investment can compensate for decreased physical attractiveness within the domain of women’s mate preferences.
Abstract: Few material goods entail as high a cost and carry as little practical value as an engagement ring. Despite their obvious signaling value, engagement ring expenditures have rarely been studied. The purpose of the current study was to experimentally manipulate a discrepancy in the physical attractiveness of romantic partners to determine its effect on hypothetical engagement ring purchases. We predicted that (1) men would purchase larger, more expensive engagement rings when imagining themselves mated to a more attractive rather than less attractive woman and (2) women would desire larger, more expensive engagement rings when imagining themselves mated to a less attractive rather than more attractive man. We further predicted a positive correlation between women’s self-ratings of attractiveness and the size and cost of the engagement ring women chose, regardless of target attractiveness. Results supported all three predictions. Data about the cost and quality of actual engagement rings was also collected to explore their correlations with age and attractiveness discrepancies in real-world couples; however, we failed to find a consistent pattern whereby more desirable women received more expensive and higher quality engagement rings. Results from the experimental portion of the current study show that men invest greater resources in attractive women and that increased resource investment can compensate for decreased physical attractiveness within the domain of women’s mate preferences.
Children’s gender-stereotypical dress and appearance might be one of the first representations of children’s emerging sense of gender identity; surprisingly, mothers’ gender-role attitudes were not significantly associated with toddlers’ gender-typed appearance
The Roles of Self-Socialization and Parent Socialization in Toddlers’ Gender-Typed Appearance. May Ling et al. Archives of Sexual Behavior, https://link.springer.com/article/10.1007/s10508-018-1263-y
Abstract: Children’s gender-stereotypical dress and appearance might be one of the first representations of children’s emerging sense of gender identity. Gender self-socialization theories posit that as children become more aware of gender categories, they become motivated to adhere to gender stereotypes, such as by expressing interest in dressing in feminine or masculine ways. Socialization theories predict that children’s gender-typed appearance reflects parents’ choices. For example, gender-traditional parents might dress their children in gender-stereotypical ways. At the same time, dressing in gender-stereotypical ways might contribute to children’s growing awareness of gender categories. The current study investigated the factors associated with gender-typed appearance among 175 (87 girls, 88 boys) Mexican American, Dominican American, and African American 2-year-olds. We examined both child and parent contributions to early gender-typed appearance. To measure children’s early conceptual understanding of gender categories, we assessed children’s use and recognition of gender verbal labels. To examine the influence of parent socialization, we assessed mothers’ gender-role attitudes. Children’s gender-typed appearance was observed and coded during an assessment. Surprisingly, mothers’ gender-role attitudes were not significantly associated with toddlers’ gender-typed appearance. However, toddlers’ gender labeling was associated with their gender-typed appearance, suggesting that self-socialization processes can be found as early as 24 months of age.
Abstract: Children’s gender-stereotypical dress and appearance might be one of the first representations of children’s emerging sense of gender identity. Gender self-socialization theories posit that as children become more aware of gender categories, they become motivated to adhere to gender stereotypes, such as by expressing interest in dressing in feminine or masculine ways. Socialization theories predict that children’s gender-typed appearance reflects parents’ choices. For example, gender-traditional parents might dress their children in gender-stereotypical ways. At the same time, dressing in gender-stereotypical ways might contribute to children’s growing awareness of gender categories. The current study investigated the factors associated with gender-typed appearance among 175 (87 girls, 88 boys) Mexican American, Dominican American, and African American 2-year-olds. We examined both child and parent contributions to early gender-typed appearance. To measure children’s early conceptual understanding of gender categories, we assessed children’s use and recognition of gender verbal labels. To examine the influence of parent socialization, we assessed mothers’ gender-role attitudes. Children’s gender-typed appearance was observed and coded during an assessment. Surprisingly, mothers’ gender-role attitudes were not significantly associated with toddlers’ gender-typed appearance. However, toddlers’ gender labeling was associated with their gender-typed appearance, suggesting that self-socialization processes can be found as early as 24 months of age.
No evidence that facial attractiveness, femininity, averageness, or coloration are valid health cues in young adult women
No evidence that facial attractiveness, femininity, averageness, or coloration are valid health cues in young adult women. Ziyi Cai et al. https://osf.io/f9tu2/
Description: Previous reports that women with attractive faces are healthier have been widely cited as evidence that sexual selection has shaped human mate preferences. However, evidence for correlations between women’s physical health and facial attractiveness is equivocal. Moreover, positive results on this issue have generally come from studies of self-reported health in small samples. The current study took standardized face photographs of women who completed three different health questionnaires (Ns=582, 583, 572). Of these women, 221 also provided a saliva sample that was assayed for immunoglobulin A (a marker of immune function). Analyses showed no significant correlations between rated facial attractiveness and either scores on any of the health questionnaires or salivary immunoglobulin A. Furthermore there was no compelling evidence that objective measures of sexual dimorphism of face shape, averageness of face shape, or facial coloration were correlated with health. These null results do not support the prominent and influential assumption that women’s facial attractiveness is a health cue, at least in young adult women.
Description: Previous reports that women with attractive faces are healthier have been widely cited as evidence that sexual selection has shaped human mate preferences. However, evidence for correlations between women’s physical health and facial attractiveness is equivocal. Moreover, positive results on this issue have generally come from studies of self-reported health in small samples. The current study took standardized face photographs of women who completed three different health questionnaires (Ns=582, 583, 572). Of these women, 221 also provided a saliva sample that was assayed for immunoglobulin A (a marker of immune function). Analyses showed no significant correlations between rated facial attractiveness and either scores on any of the health questionnaires or salivary immunoglobulin A. Furthermore there was no compelling evidence that objective measures of sexual dimorphism of face shape, averageness of face shape, or facial coloration were correlated with health. These null results do not support the prominent and influential assumption that women’s facial attractiveness is a health cue, at least in young adult women.
List of the 20 most charismatic animals. The majority are large exotic, terrestrial mammals. These species were deemed charismatic, mainly because they were regarded as beautiful, impressive, or endangered
The twenty most charismatic species. Céline Albert, Gloria M. Luque, Franck Courchamp. PLOS, https://doi.org/10.1371/journal.pone.0199149
Abstract: Charisma is a term commonly used in conservation biology to describe species. However, as the term “charismatic species” has never been properly defined, it needs to be better characterized to fully meet its potential in conservation biology. To provide a more complete depiction, we collected information from four different sources to define the species currently considered to be the most charismatic and to understand what they represent to the Western public. First, we asked respondents of two separate surveys to identify the 10 animal species that they considered to be the most charismatic and associate them with one to six traits: Rare, Endangered, Beautiful, Cute, Impressive, and Dangerous. We then identified the wild animals featured on the website homepages of the zoos situated in the world’s 100 largest cities as well as on the film posters of all Disney and Pixar films, assuming in both cases that the most charismatic species were generally chosen to attract viewers. By combining the four approaches, we set up a ranked list of the 20 most charismatic animals. The majority are large exotic, terrestrial mammals. These species were deemed charismatic, mainly because they were regarded as beautiful, impressive, or endangered, although no particular trait was discriminated, and species were heterogeneously associated with most of the traits. The main social characteristics of respondents did not have a significant effect on their choices. These results provide a concrete list of the most charismatic species and offer insights into the Western public’s perception of charismatic species, both of which could be helpful to target new species for conservation campaigns.
Abstract: Charisma is a term commonly used in conservation biology to describe species. However, as the term “charismatic species” has never been properly defined, it needs to be better characterized to fully meet its potential in conservation biology. To provide a more complete depiction, we collected information from four different sources to define the species currently considered to be the most charismatic and to understand what they represent to the Western public. First, we asked respondents of two separate surveys to identify the 10 animal species that they considered to be the most charismatic and associate them with one to six traits: Rare, Endangered, Beautiful, Cute, Impressive, and Dangerous. We then identified the wild animals featured on the website homepages of the zoos situated in the world’s 100 largest cities as well as on the film posters of all Disney and Pixar films, assuming in both cases that the most charismatic species were generally chosen to attract viewers. By combining the four approaches, we set up a ranked list of the 20 most charismatic animals. The majority are large exotic, terrestrial mammals. These species were deemed charismatic, mainly because they were regarded as beautiful, impressive, or endangered, although no particular trait was discriminated, and species were heterogeneously associated with most of the traits. The main social characteristics of respondents did not have a significant effect on their choices. These results provide a concrete list of the most charismatic species and offer insights into the Western public’s perception of charismatic species, both of which could be helpful to target new species for conservation campaigns.