More than a token photo: humanizing scientists enhances student engagement.

Despite broad consensus that highlighting counter-stereotypical scientist role models in educational materials promotes equity and success, the specific elements that make these materials effective remain untested. Are pictures of counter-stereotypical scientists enough to communicate to students that scientists come from a variety of backgrounds, or is additional information required? To parse the effects of including visual depictions and humanizing information about scientists featured in biology course materials, we distributed three randomized versions of assignments over several academic terms across 36 undergraduate institutions (n > 3700 students). We found that including humanizing information about scientists was key to increasing student engagement with the biology course materials. The positive effect of humanizing information was especially important for students who related to the scientists. Structural equation modelling revealed the extent to which students related to scientists mediated the positive effect of humanizing descriptions on student engagement. Furthermore, our results were strongest among students who shared one or more excluded identity(s) with the featured scientists. Our findings underscore the importance of providing students with examples of humanized and relatable scientists in classrooms, rather than simply adding a photo to increase representation.