Monday, August 8, 2011

The Mystery of Birthday Clusters

by Julia Buckley

Long ago my school friend Lydia suggested to me that she believed in a phenomenon which she called "birthday clusters." Basically this was the idea that we are somehow drawn to, or at least brought together with, people who have birthdays around the same time.

It's easy to poo-poo this idea until I apply it to my own life: first, the August cluster: August 5th was my mother's birthday, but August also marks birthdays for my father (who turns 80 on the 11th), my brother, my son, my godson, my grandfather, my father-in-law, and several of my friends.

Then there is the December cluster: I was born in December, as was my college roommate, both of my next-door neighbors, my sister-in-law. And most interesting of all, when I became pregnant for the first time, I was given a due date of my own birthday. My son was born a week early, so we celebrate our December birthdays one week apart.

I've met many women who gave birth to children on their own birthdays--a phenomenon I always considered fascinating, considering that they had 364 other possible days on which to birth a child.

My husband tells me this is mere coincidence, and it may well be--or perhaps are we drawn to people who make their imprint on the world at a certain time, in certain months? Do any of you have birthday clusters in your lives?

And happy birthday to all members of the August cluster. :)


Sheila Connolly said...

In my family there were many unrelated family events clustered in April-May (birthdays, anniversaries). I had to laugh when my daughter was born in March, because she moved to the front of the list.

My sister and I were both born in May, but that's because my parents always took a beach vacation in August...

Kathleen George said...

My brother and one of my sisters and I are all in the first week of July. This may say something about my parents and cold weather, though. I love the idea of clusters, though. We always laugh in my playwriting classes that so many people write about the same things in any one assignment. It's kind of like women in dorms unconsciously coordinating their periods. "There are more things in heaven and earth," right?

Julia Buckley said...

Sheila, it's just a phenomenon in families, isn't it?

Kathleen, that's a great point--a sort of innate alignment. :)

Mike Dennis said...

Julia, I've always been intrigued by the oddity of birthdays and their proximity to one another. Here's a little something that may be relevant.

You know of course that you would need to put 367 people in one room in order to be 100% certain that at least two people had the same birthday (one for each of 365 different days + Feb 29 + 1). Naturally, if you had 363 people in a room, or even 358, it's a near certainty you'll find at least two with the same birthday.

But how many people need to be in a room to have a 50-50 chance of two of them having the same birthday? Answer: 40.

Stunning, but true. It was demonstrated to me in a college math class that contained exactly 40 students. The prof started at the front of the room, telling each student to say his birthday. As soon as someone else heard their birthday, they were to speak up. The very first student's birthday was also mine.

Back during my professional musician days, I was in a four-piece band. Two of the members' birthdays were one day apart and the third member's birthday was the same as mine.

Julia Buckley said...

That's pretty fascinating, Mike, and you're right--those odds are hard to believe. But I was never a numbers person. :)