Concision

(1) When schools of fish gather again after time apart, they will swim around each other while waving their fins and performing elaborate dances. (2) Stingrays have been seen frolicking over fields of coral, twirling and flapping their wings, even when ample open ocean is readily available. (3) Some have argued that these kinds of behaviors show that fish can feel emotions like joy and delight.

(4) Even advocates for the argument that fish have feelings acknowledge that scientists can easily misidentify what they are seeing with their eyes. (5) The shape of a fish’s mouth makes it look like it is surprised; it looks that way even when it is excited or in danger. (6) Fish are social, communicating underwater using clicks and bubbles. (7) Feelings are challenging to understand even in humans, who have the ability to talk about their emotions.

(8) Many oceanographers who devote their time to studying fish behavior have argued that at least some fish, such as triggerfishes and eels, have strong feelings like the ones we experience as humans. (9) Other researchers are doubtful. (10) They argue that it has not yet been proven that fish feel emotion in any reliable, reproducible scientific experiments.

(11) Regardless, scientific consensus on the question of fish emotion is beginning to shift. (12) Many biologists have accepted that fish most likely have “primary” emotions such as fear or anger. (13) These responses seem to be found in most fish. (14) For instance, a zebrafish will avoid a part of the tank where it was once shocked even if the shock has been removed. (15) Additionally, scientists believe that feelings can be inferred from fishes’ changes in activity and eye movement, or even from involuntary responses like scale shedding. 

Which of the following is the best version of the underlined portion of sentence 1 (reproduced below)?

When schools of fish gather again after time apart, they will swim around each other while waving their fins and performing elaborate dances.