The ability to change color in response to aggression may play an important role in social hierarchy and communication among these fish. These adaptations are a striking reminder of the diversity and complexity of marine life and the evolutionary strategies that emerge to meet the challenges of the aquatic environment.

Domain signaling

Dominance signaling is an important aspect of animal behavior, especially in social species where dominance hierarchy plays a crucial role in group organization. In marine life, many species, such as fish, crustaceans, and cetaceans, use a variety of visual, vocal, and behavioral signals to establish and maintain their position in the social hierarchy.

Color change during periods of aggression, as seen in the Celebes medaka mentioned earlier, is an example of dominance signaling. In this context, color change can serve as a means of visual communication to indicate superiority or submission during social interactions, helping to avoid unnecessary conflict or establish power relations within the group.

This signaling can involve a variety of behaviors, such as specific body postures, displays of vibrant colors, distinct vocalizations, and even physical confrontations, depending on the species and the environment in which they live. These signals play a fundamental role in structuring animal societies and maintaining social order within groups.

Color change as an indication of physical fitness

The ability to change color can also be an indicator of physical fitness in many animal species, including some marine life. In some cases, the intensity of colors displayed by an animal can reflect its health, stamina, and physical vigor, making it an important signal to potential breeding partners or competitors.

For example, in fish such as the dragonfish (Pterois) mentioned earlier, bright, vibrant coloration can be an indicator of health and strength, conveying information about the genetic quality and physical condition of the individual. In competitions for resources, territory, or mates, individuals with more intense colors may be perceived as more dominant and therefore more capable of competing successfully.

Furthermore, in species where sexual selection plays an important role, such as many ornamental fish, the ability to display bright and elaborate colors can attract potential mates by demonstrating the genetic quality and fitness of the individual for reproduction.

Therefore, color change in response to factors such as aggression or environmental stimuli may not only play a role in social communication and dominance signaling, but may also serve as a visual cue of fitness and health in particular species.