Not Exactly like your Mother: Children’s Understanding of Genetic Inheritance for Familiar and Unfamiliar Animals

• In Event: The role of experience and beliefs in children’s biological reasoning

Abstract

Genetic inheritance is a fundamental concept in biology, as it is the mechanism for the transmission of traits. Therefore, understanding genetic inheritance is pivotal for science education and biological reasoning. Prior work on children’s understanding of genetic inheritance suggests children have a “mother bias” such that, if parents have different traits, children think that offspring will have the same trait as the mother rather than the father. However, this pattern might be due to prior work only allowing children to select one possible offspring. In this study, we examine children’s genetics reasoning using a new task.
Children 4 to 11 years old (N=91) completed the study at a local children’s museum. We showed them a set of parents from either a familiar or unfamiliar mammal species, in which the two parents had either the same or different color eyes. Then, we showed them multiple images of the same animal species that had eye colors that either matched the parents (light or dark), blended the parents’ eye color (either by mixing the colors or having one eye of each color), or were purple (a color not found in any mammal species; see Figure 1.). Children judged whether each of the offspring presented was possible, given the set of parents.
Children endorsed more offspring as possible when parents had different eye colors (M = 3.42, SD = 1.15) than when they had the same eye color (M = 2.67, SD = 1.44), χ2(1, N = 91) = 53.14, p < .001. Children were equally likely to endorse offspring with dark and light eyes, χ2(1, N = 91) = 1.09, p = .179. They were more likely to endorse offspring with dark and light eyes than with blended eye colors (dark: χ2(1, N = 91) = 9.22, p = .002, light: χ2(1, N = 91) = 8.27, p = .004) and more likely to endorse offspring with blended eye colors than purple eyes, χ2(1, N = 91) = 37.74, p < .001. Children were more likely to endorse the blended eye colors when the parents had different eye colors, χ2(1, N = 91) = 4.41, p = .036. Older children were also less likely than younger children to endorse offspring with purple eyes, χ2(1, N = 91) = 6.66, p = .010. We did not find any other age-related changes. In addition, animal familiarity did not influence performance.
Overall, our study highlights that from the age of 4, children have a sophisticated understanding of inheritance. Children understand that offspring can look different from their parents, as they endorsed multiple possible offspring. As seen in Figure 2, children were not more likely to choose the mother’s eye color; therefore, they did not show the mother bias that has been reported in prior literature. Additionally, children’s reasoning changed with age, as older children were less likely to endorse purple eyes (which are not found in nature for mammals). Interestingly, familiarity did not influence children’s understanding of genetics, suggesting that children appropriately generalize their understanding of inheritance to novel species.

Authors

• David Menendez, University of Michigan - Ann Arbor
  Presenting Author

• Olympia N Mathiaparanam, University of Wisconsin - Madison
  Non-Presenting Author

• Andrea Marquardt Donovan, University of Wisconsin - Madison
  Non-Presenting Author

• Vienne Seitz, University of Wisconsin-Madison
  Non-Presenting Author

• David Liu, University of Oklahoma
  Non-Presenting Author

• Karl S Rosengren, University of Wisconsin-Madison
  Non-Presenting Author

• Martha Wagner Alibali, University of Wisconsin - Madison
  Non-Presenting Author

• Chuck Kalish, Society for Research in Child Development (SRCD)
  Non-Presenting Author