Diagramsdescribingrelationshipbetweenorganisms,andtheiroverallevolution,com-monly in the form of phylogenetic trees or other evolutionary diagrams, havebecomea part of even lower secondary biology textbooks. These diagrams can help promotebasic science literacy, yettheir designmayalso strengthenmisconceptions aboutevo-lution.
Therefore, based on the content analysis of 112 Czech biology textbooks forsecondary schools (ISCED levels 2 and 3), characteristics of introduced phylogenetictrees and other evolutionary diagrams were recorded and evaluated according to thecladistics to see if their construction supports the current scientific understanding ofevolution.Thecontentanalysisindicatesthatthedesign ofnearlyhalfofalldiagramsin currentlower (ISCED2) anduppersecondary (ISCED3) textbooks promotes lad-der thinking. More than 80% of all diagrams were not accompanied by instructionson how to read them, meaning that students did not have sufficient scaffolding tounderstand them.
Mainly ISCED 3 textbooks did not introduce additional problemtasksthatwouldsupporttheuseofthediagrams inthelessons. Therefore, authorsoftextbooks should focus more on theconstruction qualityof these diagrams while alsosupporting their correct application during the educational process.
This is likely toprevent a further increase in student misconceptions.