You’re tall, statuesque, ruggedly good-looking—at least moderately so—and yet your girlfriend’s family just isn’t warming up to you. What gives?
Simple: They have different priorities. Your girlfriend sees you as her partner, but her mother and sister are only grading you as a potential member of their family—and that's a problem of genetics and evolution, according to research from The Norwegian University of Science and Technology.
"We see a conflict between mother and daughter because of opposing interests," study co-author Robert Biegler said in a press release. Your girlfriend's mom wants her daughter to date respectable men with "promising prospects"—like a high-paying job, deep pockets, or a strong family lineage—because they're looking out for their offspring in terms of survival.
As for your girlfriend's sister? She likewise prefers a guy who's safe and reliable, even if that means he's lacking in the looks and personality department. And yet even though your (hopefully) future sister-in-law prefers a square for her sister, when choosing for herself, she wants a hunk of her own.
This phenomenon is called the "Juliet effect" after the famed conflict between Juliet and her mother in Shakespeare's drama. Juliet's mother hates Romeo and prefers Paris, the nice guy from a great family. Juliet, on the other hand, loves Romeo, even though he spends most of his time wandering around Italian cities, getting in fights with his buddies.
"For their own partners, women focus on an attractive appearance that suggests good health and an ability to pass on their genes," the researchers explain. "At the same time, they prioritize qualities in their sister's partner [you] that can provide direct benefits for the whole family."
Your girlfriend's mom and sister want her potential husband to have a genetic advantage—to bring a lot to the table, so to speak—that provides direct benefits like wealth or status to the family as a whole. (They don't want to get stuck raising or supporting your children if your job doesn't make enough money; they want to ensure and increase the survival and status of their own children, the researchers explain.)
To come to these conclusions, researchers provided female students and their sisters with a survey. The women were asked to rank 133 different characteristics describing the "perfect partner" for themselves or their sister. (This was cross-analyzed with a similar survey conducted among mothers and daughters a few years ago.)
"For the most part, women choose the same ideal partner characteristics for themselves as for their sister," Biegler says. "The qualities of faithfulness, loyalty, honesty, trustworthiness and reliability score highest when women are asked who would make an ideal partner." But differences were also quite clear and evident. "The women perceived characteristics like being understanding, empathetic, responsible, helpful, sensible and kind as more important for their sister's partner than for their own," Biegler adds.
What's more, women will prioritize sincerity, humor, charm, and excellent, ahem, skills in the sack as more important for their own partner than their sister's.
Our advice? Prove your self-worth. If you are, indeed, a free-loader who doesn't work and has no personal drive, re-evaluate your life and make some changes. If you're a law-abiding citizen who pays his taxes on time, volunteers every now and again, and you're working your way up in your company—let it be known.