All traits are functional: an evolutionary viewpoint 

 -  Trends in Plant Science, 26(7), p.674-676, 2021 .
<br/><br/> There is increasing confusion regarding the term 'functional trait' and its links with ecosystem functioning. Functional traits are defined as traits that affect individual fitness. I use an evolutionary rationale that considers the integration of the phenotype, the environmental variation, and the relationship between both, to propose that all traits are functional.