Commentary: Best practices for performing olfactory behavioral assays on aquatic animals: A guide for comparative physiologists.

As more physiologists start to incorporate animal behavior into their experiments, especially in the olfactory behavior research field, some considerations are often overlooked, partly due to the inherited way that physiological experiments are traditionally designed and performed. Here we highlight some of these subtle but important considerations and make a case for why these might affect the results collected from behavioral assays. Our aim is to provide useful suggestions for increased standardization of methods so they can be more easily replicated among different experiments and laboratories. We have focused on areas that are less likely to be mentioned in the materials and methods section of a manuscript such as starvation, preliminary experiments, appropriate sample sizes and considerations when choosing an odorant for an assay. Additionally, we are strongly cautioning against the use of alarm cue to generate behavioral responses due to its highly unstable chemical properties/potency. Instead, we suggest using pure chemicals (made up of one known molecule) such as amino acids, bile acids, or polyamines that are commercially available and easier to make up in known concentrations. Lastly, we strongly suggest using environmentally relevant concentrations of these odorants. We believe these guidelines will help standardize these assays and improve replication of experiments within and between laboratories.