Research Findings: Anthropomorphism--the attribution of human characteristics to nonhuman entities--has long been a staple of children's media. However, children's experiences with anthropomorphic media may interfere with biological reasoning instead encouraging an anthropocentric view of the natural world. To date, little research has addressed the typical content of children's storybooks about animals: Do these storybooks present factual information that may support early developing biological reasoning, or do they instead focus on human-centered, psychological information that may encourage anthropocentrism? We analyzed the types of causal explanatory information that commercial storybooks about animals provide to children about 2 biological concepts that have been extensively studied in the experimental literature: biological inheritance and the transmission of illness. Using coding schemes similar to those used in prior experimental literature to assess preschool-age children's biological reasoning, we found that none of the anthropomorphized books presented children with scientifically accurate causal mechanisms. These books focused almost exclusively on social-emotional experiences as opposed to biological explanations, which may inadvertently encourage anthropocentric reasoning. Practice or Policy: Understanding more about the content of informal sources of early learning can help inform educators on how to best support developing knowledge about the natural world and biological properties.