Gerudo Tribe - Random Theory Stuff

(yes, I know I think way too far into this, but here it goes!)

If you follow the Legend of Zelda game series, you've probably heard of the Gerudo tribe. They are the people that Link's arch nemesis, Ganondorf, grew up with and was the proud king of. Another thing you might know is that a male is born into the race approximately every hundred years. Now, thinking further into this statement, how is this possible? Here are some things that make this difficult to be true:

-In order for a race or tribe to keep existing, they need to have children, and would need to reproduce with men their own race

-There is very little chance ONLY women could be born into a tribe/race for that long a time

-If all the women reproduced with only that ONE male, it would cause lots of inbreeding because all of the children would be related

-The male Gerudo would have to live for a VERY long time, and literally have children with his own children

-Even then, female Gerudos would have to have children with men from other tribes or of other races

In Ocarina of Time, a Gossip Stone tells you that Gerudos sometimes go to Castle Town to look for boyfriends.. but again that's only SOMETIMES. And also, if Gerudo women keep having children with Hylian men, wouldn't that shorten the gene pool and make the race closer to dying out?

I don't know, all I'm saying is that it is next to impossible for a Gerudo male to be born every hundred years, let alone for the Gerudos to survive for that long a time. (YES I KNOW I HAVE NO LIFE)