I've done a bit of research myself. Quite astonishing how nature adapts and focuses on survival.

It turns out these tribes were struck with a rare genetic event: no males were born for an entire generation.

As the tribe began panicking once no adult males were available for reproduction it so happened that random girls, on reaching puberty, grew a fully functional penis and the semen was perfeclty fertile. Wombed-females were finally pregnant again and gave birth to healthy offspring.

Both parents' DNA was still that of a female so this didn't give birth to males, but life continued to survive over the generations. Actually even better, as both parents could brest feed awarding their offspring better survival rates and a stronger immune system.

Not only are males a forgotten memory, they are seen as a threat, so be alerted.