Jane, it seems to me this dominance-asserting behavior is quite typically male (although I'll confess to having engaged in it myself, when feeling utterly annoyed by uninformed assertions). But the name-calling is utterly pathological. These are "ad hominem" attacks and reflect the attacker's insecurity--his inability to say anything rational about the topic at hand. Such verbal attacks are intended to cut to the core and leave the victim bleeding emotionally. These are the vicious, unconscionable weapons of internet trolls.