Metaphor-based metaheuristics, a call for action: The elephant in the room

Claus Aranha, Christian Leonardo Camacho-Villalón, Felipe Campelo*, Marco Dorigo, Ruben Ruiz, Marc Sevaux, Kenneth Sörensen, Thomas Stützle

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Taking inspiration from natural behaviors to devise new optimization algorithms has played an important role in the history of the field of metaheuristics (Sörensen et al. 2017). Unfortunately, in the last two decades we have been witnessing a new trend by which dozens of metaphor-based metaheuristics based on the most diverse possible set of natural, artificial, social, and sometimes even supernatural phenomena and behaviors are proposed, without a clear motivation beyond the desire of their authors to publish their papers. Despite several attempts (Sörensen 2015; Sörensen et al. 2019; Weyland 2010; Piotrowski et al. 2014; Fong et al. 2016; Camacho Villalón et al. 2019; Camacho Villalón et al. 2020; Swan et al. 2015; Lones 2020; Tzanetos and Dounias 2020) to put an end to the flood of increasingly outlandish, “novel” metaphor-centered metaheuristics, there is still a steady inflow of such papers submitted, and often accepted for publication. For many reasons, we believe this is detrimental to the field of metaheuristics. This letter describes some of the negative effects of publishing such papers in the literature and proposes a necessary action to try to put a limit to this highly undesirable phenomenon.
Original languageEnglish
Pages (from-to)1-6
Number of pages6
JournalSwarm Intelligence
Early online date30 Nov 2021
Publication statusPublished - Mar 2022

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