Y'know I am strangely curious as to why my baby will wake suddenly when I put her down, but will…

Y'know I am strangely curious as to why my baby will wake suddenly when I put her down, but will full on sleep through a sound of thunder, glasses breaking, alarm clocks going off, etc...then I realized her daddy does the same (well, not for being put down for bed :P I don't usually carry him off to bed.)