It doesn't become an advantage if lefties are just as common as righties.

但如果左撇子和右撇子一样常见的话，那么它也不会演变成这种优势的。

youdao

If both parents are left handed, 50% of their offspring will be left-handed. Two righties only have a 2% chance of having a lefty.

如果双亲都是左撇子，他们的孩子有50%的可能是左撇子。两个右撇子的人生出左撇子的孩子的几率只有2%。

youdao

If both parents are left handed, 50% of their offspring will be left-handed. Two righties only have a 2% chance of having a lefty.

如果双亲都是左撇子，他们的孩子有50%的可能是左撇子。两个右撇子的人生出左撇子的孩子的几率只有2%。

youdao