...Her species would have to reproduce somehow. And, when one gets down to it, sexual reproduction basically boils down an exchange of chemicals. So why not see what would happen if two females could just exchange their chemicals and make a child without a man? After all, flowers needed no differing sexes between them to create seeds.
And parthenogenisis (spontaneous virgin birth) was a thing that could happen, although Linda had never seen or heard of any actual cases of it.
So, with a flick of her mental finger, human sex (or at least this version of it) was forever redefined. Two females could now insert their fluids into each other with their fingers, or else ejaculate into one another to produce what would, in nine months, eventually become a child.
Granted, this could lead to less of a need for men or something like that, but Linda was too excited to try out this plan to do much long-term thinking.
And so it went that Ashley returned home to the couple's shared cave to find Eve waiting for her, leaning seductively against the wall of the cave, her bare boobs practically in Ashley's face.
If only Linda could hear what they were saying.
Whatever it was, it must have worked, because Ashley practically threw down her meat animal carcass and came over to Eve.