Fluctuating asymmetry in ecological and environmental research: Quo vadis?

Abstract

<ol><li>Májeková et al. (2024) demonstrated that leaf fluctuating asymmetry (FA) is not a reliable indicator of stress. I broaden the perspective on the findings by these authors.</li><li>High prevalence of confirmation bias could explain why as much as 39% of 131 unique entries (plant species × stress type) in the database of published studies compiled by these authors showed the significant increase in FA with stress.</li><li>The use of blind methods should be considered obligatory for any study addressing environmental or genetic impacts on FA.</li><li>Both data and conclusions from FA-related studies that did not report blinding should only be used when proof of negligible impact from confirmation bias can be provided.</li><li>It is essential that all measures taken against biases are described in each submitted manuscript, and that the need to check for these requirements is included in instructions for reviewers.</li></ol>