The role of genetic essentialism and genetics knowledge in support for eugenics and genetically modified foods.

People are regularly exposed to discussions about the role of genes in their lives, despite often having limited understanding about how they operate. The tendency to oversimplify genetic causes, and ascribe them with undue influence is termed genetic essentialism. Two studies revealed that genetic essentialism is associated with support for eugenic policies and social attitudes based in social inequality, and less acceptance of genetically modified foods. These views about eugenics and genetically-modified foods were especially evident among people who had less knowledge about genes, potentially highlighting the value of education in genetics.

Considering cross-cultural differences in sleep duration between Japanese and Canadian university students.

Sleep is a fundamental biological process that all humans exhibit, and there is much evidence that people suffer adverse health outcomes from insufficient sleep. Despite this evidence, much research demonstrates significant heterogeneity in the amounts that people sleep across cultures. This suggests that despite serving fundamental biological functions, sleep is also subject to cultural influence. Using self-report and actigraphy data we examined sleep among European Canadian, Asian Canadian, and Japanese university students. Significant cultural differences emerged in terms of various parameters of sleep (e.g. sleep time), and beliefs about sleep (e.g. perceived relation between sleep and health). Despite sleeping significantly less than European Canadians, Japanese participants slept less efficiently, yet reported being less tired and having better health. Moreover, relative to European Canadians, Japanese participants perceived a weaker relation between sleep and physical health, and had a significantly shorter ideal amount of sleep. Asian Canadians' sleep behaviors and attitudes were largely similar to European Canadians suggesting that people acculturate to local cultural sleep norms.

Exploring people's thoughts about the causes of ethnic stereotypes.

Much research has shown that people tend to view genes in rather deterministic ways-often termed genetic essentialism. We explored how people would view the causes of ethnic stereotypes in contexts where human genetic variability was either emphasized or downplayed. In two studies with over 1600 participants we found that people viewed ethnic stereotypes to be more of a function of underlying genetics after they read an article describing how ancestry can be estimated by geographic distributions of gene frequencies than after reading an article describing how relatively homogeneous the human genome was or after reading a control essay. Moreover, people were more likely to attribute ethnic stereotypes to genes when they scored higher on a measure of genetic essentialism or when they had less knowledge about genes. Our understanding of stereotypes is a function of our understanding of genetics.

Making Sense of Genetics: The Problem of Essentialism.

"Psychological essentialism" refers to our tendency to view the natural world as emerging from the result of deep, hidden, and internal forces called "essences." People tend to believe that genes underlie a person's identity. People encounter information about genetics on a regular basis, as through media such as a New York Times piece "Infidelity Lurks in Your Genes" or a 23andMe commercial showing people acquiring new ethnic identities as the result of their genotyping. How do people make sense of new scientific findings that are inherently complex if they don't have years of specialized training and education at their disposal? Given the substantial overlap between a lay understanding of genetics and lay intuitions about essences, we argue that, when most people are thinking about genes, they are not really thinking about genes in the complex ways that good scientists are. Combating people's essentialist biases can be a formidable challenge. Although we have identified some promising results of trying to reduce people's genetic essentialist tendencies, there is still much to learn about how these essentialist biases can be countered. It is important to help people understand genetic information so they are able make well-informed decisions about their lives.

The double-edged sword of genetic accounts of criminality: causal attributions from genetic ascriptions affect legal decision making.

Much debate exists surrounding the applicability of genetic information in the courtroom, making the psychological processes underlying how people consider this information important to explore. This article addresses how people think about different kinds of causal explanations in legal decision-making contexts. Three studies involving a total of 600 Mechanical Turk and university participants found that genetic, versus environmental, explanations of criminal behavior lead people to view the applicability of various defense claims differently, perceive the perpetrator's mental state differently, and draw different causal attributions. Moreover, mediation and path analyses highlight the double-edged nature of genetic attributions-they simultaneously reduce people's perception of the perpetrator's sense of control while increasing people's tendencies to attribute the cause to internal factors and to expect the perpetrator to reoffend. These countervailing relations, in turn, predict sentencing in opposite directions, although no overall differences in sentencing or ultimate verdicts were found.

Can merely learning about obesity genes affect eating behavior?

Public discourse on genetic predispositions for obesity has flourished in recent decades. In three studies, we investigated behaviorally-relevant correlates and consequences of a perceived genetic etiology for obesity. In Study 1, beliefs about etiological explanations for obesity were assessed. Stronger endorsement of genetic etiology was predictive of a belief that obese people have no control over their weight. In Study 2, beliefs about weight and its causes were assessed following a manipulation of the perceived underlying cause. Compared with a genetic attribution, a non-genetic physiological attribution led to increased perception of control over one's weight. In Study 3, participants read a fictional media report presenting either a genetic explanation, a psychosocial explanation, or no explanation (control) for obesity. Results indicated that participants who read the genetic explanation ate significantly more on a follow-up task. Taken together, these studies demonstrate potential effects of genetic attributions for obesity.

Do scientific theories affect men's evaluations of sex crimes?

Evolutionary psychology accounts of gender differences in sexual behaviors in general and men's sexual aggression, in particular, has been criticized for legitimizing males' sexual misconduct. To empirically assess such critiques, two studies examined how men's judgments of male sex crimes (solicitation of sex from a prostitute; rape) are influenced by exposure to (a) evolutionary psychological theories and (b) social-constructivist theories. Across two studies, a consistent pattern emerged compared with a control condition (a) exposure to evolutionary psychology theories had no observable impact on male judgments of men's criminal sexual behavior, whereas (b) exposure to social-constructivist theories did affect judgments, leading men to evaluate sex crimes more harshly. Additional results (from Study 2) indicate that this effect is mediated by perceptions of male control over sexual urges. These results have implications for journalists, educators, and scientists. Aggr. Behav. 37:440-449, 2011. © 2011 Wiley-Liss, Inc.

Evidence for a sensitive period for acculturation: younger immigrants report acculturating at a faster rate.

Though recent adult immigrants often seem less acculturated to their new society than people who immigrated as children, it is not clear whether this difference is driven by duration of exposure or exposure during a sensitive developmental period. In a study aimed at disambiguating these influences, community and student samples of Hong Kong immigrants to Vancouver, Canada, completed the Vancouver Index of Acculturation, a measure that assesses respondents' identification with their mainstream and heritage cultures. A longer duration of exposure was found to be associated with greater identification with Canadian culture only at younger ages of immigration, but not at later ages of immigration. Conversely, identification with Chinese culture was unaffected by either age of immigration or length of exposure to Canadian culture. These findings provide evidence for a sensitive period for acculturation: People are better able to identify with a host culture the longer their exposure to it, but only if this exposure occurs when they are relatively young.