how to deaL with chaoS: chooSing a Standard nomencLature with the coSt function The implementation of the cost function (Supporting Information, Appendix S2) reveals that some terms should take precedence over others. However, given the current literature review, some sets of terms are equally optimal, having equivalent individual costs (e.g. both ‘median furrow’ and ‘deep median groove’ have the same cost, appearing in equal frequencies in the surveyed references). Such cases need to be decided case-by-case on the basis of additional parameters (Supporting Information, Appendix S3, Table S1).