Satoshi Kanazawa, who often writes on gender issues from a scientific perspective, posted an article explaining why the practice of giving children their fathers’ surnames is beneficial to children:
Marilyn vos Savant may be the most intelligent person alive in the world today, with the recorded IQ of 228, and she is a wizard when it comes to solving logical and mathematical problems in her weekly column “Ask Marilyn” in the Parade magazine. But she does get at least one biological problem wrong.
vos Savant advocates a social institution where all individuals – men and women – keep their last names for life, rather than women adopting their husband’s last name upon marriage, and where all boys inherit their last names from their fathers and all girls inherit their last names from their mothers. That is why, as an adult, she changed her last name from Mach that she was born with (vos Savant is a descendent of the physicist Ernst Mach) to her mother’s maiden name, vos Savant.
Patrilineal inheritance of family names, where children inherit their last names from the father, not from the mother, evolved as a social institution as one of the mechanisms to alleviate paternity uncertainty. Like all mammalian males, human fathers can never be completely certain of their paternity, but, unlike most mammalian males, they are asked to invest very heavily in their offspring. Therein lies the possibility of cuckoldry – unwittingly investing their precious limited resources in the genetic offspring of another man. Males of only a very few species in nature (humans, and many avian species) face the danger of cuckoldry because male parental investment among these species is high … Males of these few species – human fathers in particular – therefore need to be reasonably convinced that they are indeed the genetic fathers of their putative offspring before they would agree to invest heavily in them. Both nature and social institutions aid in such an effort.
Patrilineal inheritance of family names is another social institution that emerged to convince the fathers of their paternity, by saying (if social institutions have a vocal cord) “The baby’s really yours, because it has your last name!” … Fathers are therefore expected to invest more heavily in children who bear their last names than children who bear the mother’s last names, because they are more likely to be convinced of their paternity. As a result, ceteris paribus, children who inherit their last names from their fathers are expected to be more likely to survive and thrive than children who inherit their last names from their mothers. Like polyandry, the social institution of matrilineal inheritance of last names contains the seeds of its own extinction….
Kanazawa is right. Patriarchy is indeed best for children and societies that practice it. This is why matriarchal societies are always outcompeted, and eventually lose out to stronger, patriarchal societies. Feminism results in cultural and ethnic extinction for all those who practice it for an extended period of time.