#1:
Novice Marksdwarf, Adequate Discipline, Dabbling Archer, Skilled Dodger, Novice Animal Caretaker, Novice Animal Dissector, Novice Ambusher, some social skills, no melee skills. No melee weapon, one crossbow, one quiver with 17 bolts left after combat.
#2:
Novice Marksdwarf, Dabbling Discipline, Dabbling Archer, Adequate Dodger, Novice Animal Caretaker, Novice Animal Dissector, Novice Ambusher, no melee skills. No melee weapon, one crossbow (in left hand, but AFAIK that shouldn't matter), one quiver with 19 bolts left after combat.
#3:
Novice Marksdwarf, Dabbling Discipline, Dabbling Archer, Adequate Dodger, Novice Animal Caretaker, Novice Animal Dissector, Novice Ambusher, no melee skills. No melee weapon, one crossbow, one quiver with 17 bolts left after combat. Carrying her infant child into combat, but besides from being completely crackbrained dwarfish this shouldn't influence combat behaviour, should it?
#4:
Competent Marksdwarf, Novice Shield User, Novice Armor User, Novice Discipline, Novice Observer, Dabbling Archer, Novice Dodger, Novice Fish Dissector, Novice Fish Cleaner, Novice Fisherdwarf, Novice Tracker, Novice Climber. No melee weapon, one crossbow, 15 bolts left after combat.
So no hammerers at all, the only melee skills with No.#4 dwarf and these only defensives, all had bolts and none had melees weapons. Maybe some trees obscured line of sights so the dwarves felt compelled to approach with each loss of LOS?
Cheers.