Abstract
This systematic review synthesizes results from 93 studies analysing 1083 biology textbooks. Most studies focused on high school textbooks and originated from the USA, China, Spain, Germany and Sweden. Papers primarily addressed human biology but no research examined botanical or geological topics, despite their low attractiveness for students. Studies within human biology focused mainly on topics related to reproduction, gender differences, sexuality and health in textbooks published in North America and Europe and identified ideas supporting heteronormativity and stereotypical views of gender. Conversely, papers focused on the topic of health analysed textbooks from almost all over the world and those for high schools from selected countries in South America and Asia provided insufficient coverage of the risks associated with bad nutrition (e.g., obesity). A positive trend was the increasing amount of content devoted to environmental topics in recent years but textbooks do not sufficiently emphasize the importance of individual and social behaviour change in addressing environmental challenges. Studies of genetics chapters show that textbooks do not emphasize the influence of environmental factors on the formation of traits. Analyses focused on microbiology revealed a lack of information needed to protect the health of the population; for example less than 30% of textbooks contained information that antibiotics are ineffective against viruses. The textbook analysis also revealed that graphs and tables constituted only up to 8% of all visuals. These findings highlight the need for textbook authors and curriculum developers to avoid misconceptions, emphasize diverse perspectives and integrate visual tools that support conceptual understanding.
Context and implications
Rationale for this study: Research on biology textbooks is extensive but fragmented across regions and topics. We are unaware of work aimed at understanding global patterns, key strengths and recurring gaps in biology textbook content.
Why the new findings matter: By systematically reviewing 93 studies, this paper provides a global overview of what has been analysed, highlighting underrepresented themes, persistent misconceptions and areas where textbooks fail to reflect contemporary science.
Implications for researchers, curriculum developers, educators and policy-makers: Researchers will get a clear map of existing literature to guide future studies and identify underexplored topics such as botany. Curriculum developers and textbook authors can use these findings to improve content accuracy, inclusivity and integration of visuals that support deeper conceptual understanding. Educators can recognize the limitations of current materials and design complementary strategies to address misconceptions. For policy-makers, the findings underline the importance of regularly updating textbooks to reflect current scientific knowledge and to better support biology education.