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The royal gramma (Gramma loreto) is vulnerable to anthropogenic impact in its coral reef habitats, and is deemed an “indicator” species of pollution. It is also heavily fished for the aquarium trade, being among the top 1% of imported marine aquarium fish species into the U.S. The objective of this study was to establish optimal sex ratios of broodstock groups for aquaculture as an alternative to wild capture, while balancing territorial aggression. Three two-month breeding trials were carried out in six 23 L aquaria stocked with one male and one, two, or three females. During the trials, each aquarium was filmed weekly for one hour at first light to record courtship, nest use, and aversive behaviors. Behaviors were quantified with JWatcher software and analyzed in repeated measures ANOVAs. Results suggest that in small aquaria, a sex ratio of one male to two females may be optimal for spawning because courtship and nest use behaviors are optimized while aversive behaviors are moderated. Past efforts to aquaculture the species have typically been conducted at broodstock sex ratios of 1:1. These results offer the potential to increase productivity of commercial aquaculture of the species. 

Synopsis Teeth lie at the interface between an animal and its environment and, with some exceptions, act as a major component of resource procurement through food acquisition and processing. Therefore, the shape of a tooth is closely tied to the type of food being eaten. This tight relationship is of use to biologists describing the natural history of species and given the high instance of tooth preservation in the fossil record, is especially useful for paleontologists. However, correlating gross tooth morphology to diet is only part of the story, and much more can be learned through the study of dental biomechanics. We can explore the mechanics of how teeth work, how different shapes evolved, and the underlying forces that constrain tooth shape. This review aims to provide an overview of the research on dental biomechanics, in both mammalian and non-mammalian teeth, and to synthesize two main approaches to dental biomechanics to develop an integrative framework for classifying and evaluating dental functional morphology. This framework relates food material properties to the dynamics of food processing, in particular how teeth transfer energy to food items, and how these mechanical considerations may have shaped the evolution of tooth morphology. We also review advances in technology and new techniques that have allowed more in-depth studies of tooth form and function.