Answer:

LEMMING

Answer	Crossword Clue
LEMMING	Migratory rodent
LEMMING	Mass-migrating rodent
LEMMING	Arctic rodent with suicidal bent.

LEMMING	Animal with a herd mentality
LEMMING	Victim of herd mentality
LEMMING	Animal in a mass migration
LEMMING	Hardly an independent thinker
LEMMING	Not an independent thinker
LEMMING	Epitome of herd mentality