A good example of different animals being different size. In Vietnam we armored cavalry types had to dodge RPGs all the time. Well, the RPG had stadia lines in the sight based on the size of a tank. When they shot at a personnel carrier(which is much shorter) they always shot high because the sight would say the " TANK" was further away. We had dozens of those things go sailing harmlessly overhead. The smart gunners aimed low on us or quite often got lucky and hit us high up in the gunshields which caused some personnel damage but left the vehicles running. Big deer... little deer... big Tank... little personnel carrier.[]