Science Says the First Born Child is the Most Intelligent ...

My older sister was always obsessed with turning me into her “minnie-me.” That required teaching me everything she learned from kindergarten through high school. She would also always pretend to be the teacher when we played school and mom when we played house. Turns out that playtime paid off! Older siblings become smarter by teaching; this is called the “tutoring hypothesis.”

Did your parents play favorites with your oldest sibling? Looking back that may seem harmless, but they actually robbed you of 1.5 IQ points by doing so! The more attention parents pay to their kids, the smarter they are likely to be. And it just so happens that first-born children are the center of attention for longer than their siblings who come after them.

This intelligence boost is sort of a self-fulfilling prophecy. Oldest siblings think they are smarter and hence become smarter. Talk about fake it till you make it!

Whether your family consists of just you and one other sibling or you and nine, you have to share your resources—resources being your parents’ time and attention. The higher you are in the sequence of kids in your family, the easier it is to take advantage of your resources. And more resources equals higher intelligence!

This is sad but potentially true—especially sad for someone like me who is 4/4 daughters! Some parents are biased toward their first child because that is the one they planned to have. If the subsequent kids were accidents, they don’t treat them the same way. In this case, there’s a clear reason for less attention and a lower intelligence.

Before having their first child, parents might read all the best parenting books five times to be prepared and make sure everything goes smoothly. But after the first child turns out with nothing more than a few scrapes and bruises, they put the breaks on parent-of-the-year style parenting and take a more relaxed approach.

Older siblings can usually think more abstractly than their younger siblings. While thinking differently doesn’t necessarily make you smarter, having a more creative, less concrete perspective can help you come off as more intelligent.

Science isn’t perfect—so don’t go bragging to your younger sibling about how you are a genius and they’re an idiot just yet. But this is interesting to keep in mind, especially as you raise children of your own. Do you think this is true in your family?