Fewer than three pages in a typical 1,000-page biology textbook from recent decades address climate change, according to the new study, despite climate experts’ warnings that this is one of the biggest environmental threats the world is facing. Researchers analyzed 57 textbooks published between 1970 and 2019. They counted the sentences in the books’ climate-change passages — identified by phrases such as ‘global warming’ and ‘greenhouse gas’ — and found that the median number of sentences per passage rose until the 2000s to approximately 52 but then dropped to 45 in the 2010s.

“It’s incredibly useful data,” says Mariëlle Hoefnagels, a science-education specialist at the University of Oklahoma in Norman and author of two general biology textbooks, one of which was analyzed in the study. She says that the paper’s insights concerning climate-change solutions will help her to shape a forthcoming edition of one of her books. However, “books can’t continue to grow indefinitely,” she adds.

Experts suggest that references to climate change grew in the 2000s because of a growing awareness of the problem. Joseph Henderson, an associate professor of environment and society at Paul Smith’s College who wasn’t involved in the research, argued that textbooks are only one vehicle for students to learn more about the impacts and effects of climate change, “They could be doing a better job with biology textbooks. It’s important to also think about whether and how teachers are actually using them.” (Washington Post $, Nature, Grist, The Guardian, The Hill, Space Daily)