How Many Giant Animal Movies Were There?

Them! really started it with giant irradiated ants.  YouTube has a channel of old science fiction movies, free, and you look at the titles and you see why.  The Killer Shrews, Attack of the Giant Leeches (to what do they parasite?), The Giant Gila Monster.   And other classics The Brain That Wouldn't Die, War of the Insects, Invasion of the Neptune Men, Cat Women of the Moon, The Brain Eaters!  There was a lot of money available to make horrible movies back then.