Male sperm (Y) swim faster and die sooner than female sperm(X),
Because female sperm contain heavier genetic material, which slows them down but allows them to live longer.
Males with longer penises tend to produce more male offspring because they deposit the sperm closer to the egg and Y sperm cells win the "sprint."
Males with shorter penises tend to have more female offspring because sperm is deposited further from the egg, Y sperm die off thus allowing X sperm to win the "marathon."
Look at your family. This tells you whether or not your father had a big dick.
BTW, I have 2 boys
I listen to Adam Carolla, yes I spelled his name right, he hates that so many get his name wrong, love his rants, sometimes they go on a bit thou