Social reasons:
* Schooling: Many fish species, like sardines or herring, school together for safety, feeding efficiency, and navigation. In this case, following is the norm, and the fish are likely not individually choosing who to follow.
* Pair bonding: Some fish species, like clownfish, form monogamous pairs. The follower could be the mate of the fish it's following.
* Hierarchy: In some species, there are dominant individuals. A fish might follow a dominant individual to learn feeding areas, avoid predators, or even gain social acceptance.
Survival reasons:
* Predator avoidance: If a fish sees another species flee, it might follow to avoid a predator it doesn't see.
* Food sources: A fish might follow another fish that it knows has found a good food source.
* Shelter: Some fish might follow others to find a safe place to hide, especially if it's a new environment.
Other reasons:
* Curiosity: A fish might be curious about the other fish's behavior and follow to learn.
* Mistaken identity: If the fish look similar, it could be a simple case of mistaking another fish for a member of its own school.
Ultimately, the outcome of one fish following another depends on the specific situation and the species of fish involved. It's always fascinating to observe fish behavior and try to understand their motivations!