August 8, 2024 — A new study by researchers at the Hebrew University of Jerusalem comparing twins and non-related individuals illustrates how genetically diverse groups make more accurate collective judgments than genetically homogeneous groups.

The new research, published in Personality and Individual Differences, provides the first empirical evidence of genetic diversity’s role in enhancing collective intelligence. This finding is crucial as it suggests that genetic diversity can significantly improve group decision-making processes, which has profound implications for organizational management, innovation, and our understanding of biodiversity’s role in adaptation and resilience.

“This study is the first empirical demonstration of the significant impact genetic diversity can have on collective decision-making, underscoring the importance of embracing diversity in all its forms to enhance our cognitive abilities and tackle complex challenges more effectively,” says Dr. Meir Barneron of the Hebrew University Seymour Fox School of Education. “It adds a new dimension to the ‘wisdom of crowds’ phenomenon.”

Previous studies have suggested that combining individual judgments can improve accuracy amongst groups with varied backgrounds, education, and demography. However, Dr. Barneron’s research takes this a step further by proposing that genetic diversity itself contributes significantly to decision-making accuracy.

The study involved 602 identical and fraternal twins, who participated by making numerical judgments in pairs. These pairs consisted either of co-twins (related pairs) or non-related individuals (unrelated pairs). The results revealed that judgments made by unrelated (i.e., heterogeneous) pairs were more accurate than those made by related (i.e., homogeneous) pairs.

In order to distinguish between environmental and genetic factors, the study compares the performance of related and unrelated pairs separately among identical and fraternal twins. This comparison is relevant as genetic influences make identical twins more similar to one another compared to fraternal twins because the former share virtually 100 percent of their genetic variance, whereas fraternal twins share, on average, 50 percent of the genetic variance.

The findings also revealed that the superior performance of unrelated versus related pairs was evident for the identical twins underscoring the impact of genetic relatedness on collective judgment.

This empirical evidence supports the broader theory that diversity enhances decision-making, with significant implications for organizational management. It suggests that diverse teams may be better equipped to tackle complex problems and innovate effectively.

The research paper titled “Genetically-diverse crowds are wiser” can be accessed here.

Researchers:

Meir Barneron^a, Ilan Yaniv^b, Lior Abramson^{b c}, Ariel Knafo-Noam^b

Institution:

1. Seymour Fox School of Education, Hebrew University of Jerusalem, Israel
2. Department of Psychology, Hebrew University of Jerusalem, Israel
3. Department of Psychology, Columbia University, New York, United States