Wait, what? A little too broad a statement. Natural (whatever that means) regs will hermie under adverse conditions, even outdoors. Its in the genetics alright, all marijuana has the genetic traits to express hermaphroditism. Even those "true xxx females" won't be after a gen or 2... Leave a poorch light on 24/7 with a 'bomb-proof' female growing under it outdoors, you'll see.Natural regular seeds don't hermie. It has to do with how the fem seeds are made.