Plant anatomy help?

Question

What advantage do bryophyte gameopphytes that are either male or female have over bryophyte gametophyes that have both male and female structures?

I really do not know the answer to this question for my biology class and I really can't find it in the book. Please help me. No spam answers. I hate those.

Answer 1

Probably the answer is that the condition reduces the chance of selfing.  Selfing could result in too many homozygous genes that are harmful, thus producing no or very poor sporophytes.