Is Evolution Unfair to Women?

Many of us have seen or heard the results of the recent Emory University study probing the correlation between testicular size and nurturing parenting.  It made for fun radio banter for the overgrown 12 year old DJs and talk show hosts today and the amount of awful word play I saw today when reading about this was overwhelming (see here for instance.)  

For those who may have missed it the take away from most of the conversations was that men with smaller testicles tended to get the most joy out of being more nurturing fathers.  This was not wholly surprising since we learned 2 years ago in this Northwestern University study that your testosterone levels dropped some when you remained in a relationship and significantly farther after fatherhood.  It noted that the more paternal involvement, the lower the level.  This was fascinating at the time because it challenged the old school thinking that men were only wired to hunt and women to gather and take care of the kids. 

 

What was telling about the Emory study's results was that they found that

1) Testosterone levels were not strongly tied to testicular size

2) Bigger testes were ties to stronger, higher quality sperm

These 2 facts got me thinking.  Are our daughters genetically drawn to jerks who will leave them --or at least leave them to handle the child rearing-- because it's best for the species?  That seems a little unfair, doesn't it?  How could evolution, a system which has brought us so far have come to this?  The strongest sperm, the ones voted "most likely to succeed" in their sperm class, are from fathers who are not genetically programmed to be as engaged and nurturing as their weaker sperm classmates?