Amphipods (Gammarus pseudolimnaeus) do not demonstrate a left-right preference in a 3-D printed aquatic T-maze

Abstract

Crustaceans are increasingly used as research subjects in experiments investigating learning in invertebrates. While many of these species may be useful models it is essential to document the presence or absence of behavioral laterality, especially considering the long-held belief that functional lateralization was unique to humans or other vertebrate species. Neglecting this fundamental step weakens the applicability of results and may unnecessarily complicate experimental design. Amphipods (Gammarus pseudolimnaeus) may be a useful invertebrate for studying simple discriminations or escape behavior, but research on their potential behavioral laterality is absent. The current study investigated whether amphipods demonstrate a left-right bias when navigating an aquatic T-maze by placing them in the maze and recording their choices across multiple trials. Our results suggested that amphipods do not show a strong left-right bias during initial navigation of an aquatic T-maze. These findings may encourage other researchers to test invertebrates for behavioral laterality, utilize amphipods in studies of simple forms of learning, and potentially simplify future experimental design.