at those stages it's more reflex toward food than it is aggression. similarly, however, gars show aggression by nipping at each other, shredding fins, or doing the entertaining "follow the gar" routine. in captivity they definitely seem to form a sort of social hierarchy, whereas in the wild there is more space so behavior tends to be different.
in my tank with the largest gars, the hierarchy of aggression goes like this (top to bottom of the group) croc II - Cubans - Florida/tropical - spotteds. keep in mind relative sizes of fishes will make a difference, but IMO/IME, gators and Cubans are more aggressive, TPG/SNG/FLG can be pretty similar with TPG at a slight edge, LNG tend to be the least aggressive in a group of gars...again, size is relative and these are generalizations--
--solomon
