The polydactyly gene is dominant over the common gene for finger number. Will humans ever have six fingers?
Will humans ever have six fingers?
I'm assuming you mean all/most humans here.
Unlikely. Being dominant means it will show up when present. It also makes it easier to spot. If 6 fingered people became 'desirable' and reproduced more then it's possible. But more likely it has the opposite affect and it reduces their opportunities because it is a 'strange' physical 'defect' that often will make them less desirable (less successful in producing heirs to carry the gene).
My understanding is that in general humans are slowly losing the pinky finger and in a few hundred generations we will have 3 fingers and a thumb.