Does egg shape determine gender?

[RcoM]

Did you notice a difference in the sizes of the hens? I had a columbian rock hen that I hatched 2 chicks from when crossed with a buff laced polish rooster. I only now realize they were cockerels because she was silver and he was gold. There was an EE hen I got with her from the same place and her eggs were often round. She was about half the size of the rock. She was splash so I don’t think she would have produced sex linked chicks but if I had kept those chicks long enough to see if male or female and if they were mostly female I would wonder if nature wanted the males to hatch from the largest hen of the flock.

For some reason nature always wants more roosters. I think it's for safety. 65% of eggs in any clutch are roosters, on average.

 

[Ridgerunner]

Most of my individual hatches are 2/3 to 3/4 of the same sex, sometimes boys sometimes girls. I typically hatch about 40 to 45 chicks a year. Some years I will have more boys, some years more girls. But several times I've looked at a two year average, 80 to 90 chicks. Those are practically always a 50-50 split of the sexes. You have to hatch enough for averages to mean much.

Where did you get your statistics? They do not match what I see over time.