About 80 percent of you have at least one brother or sister, and science says their influence goes way beyond whether or not you had someone to play catch with or just had to silently bounce a ball off the garage door in the driveway.
Whether or not you have siblings--and whether they were born before or after you--goes a long way toward determining what kind of person you are.
Guys, remember the torment that your older brothers put you through when you were growing up? If you are the oldest (or only) brother in your clan, then you're lucky. You didn't have a bunch of quarterbacks pulling your arms behind your back, stealing your glasses and calling you a pencil-necked little gaynerd.
Plus, your younger brothers provided ample punching practice.
If your mother spat out a few boys already before you came along, then you know the pain of having your older brothers constantly questioning your sexuality. You may be interested to learn that, according to science, they were right to do so: Having older brothers increases the probability that you will be gay.
It's called the Fraternal Birth-Order Effect, and it's quite clearly documented. For each son a woman produces, the chances that the next one will be spending his first 20 years inside a closet increase by 28 to 48 percent. By the fourth or fifth, you might begin to notice a puzzling affinity for musical theater.
Now, keep in mind the base rate of homosexuality is low already, you would need over 10 brothers before your probability of being gay propelled over 50 percent. Still, it's estimated that one in seven gay men can attribute their sexuality to this effect.
And they can take one hell of a photo.
Scientists think that this phenomenon is caused by a mother's body reacting to her son's foreign dude-proteins, and making antibodies to fight them. Each time another boy passes through a woman's system, these antibodies get stronger, and their target is your masculinity. We wish we were making that up. Before you're even born, your older brothers actually gang up on you and attempt to beat the straight out of you for nine months.
There are many benefits to having older brothers and/or sisters: they provide a reliable source of advice, they keep the bullies off your back and they can help you build up a healthy alcohol and cigarette dependency long before it's legal to do so. Now it turns out that older siblings give you someone to look up to. Literally.
Science has proven that having older siblings noticeably stunts your growth. A scientific study following 14,000 British children found that those with three siblings were, on average, one inch shorter than their peers, the youngest being the shortest.
Tom Cruise: third child out of four.
Why? They think one factor is that, along with stinky second-hand clothes and a beat up backpack, the youngest has to make do with a stretched-out, hand-me-down uterus. As a mother goes through multiple pregnancies, she tends to put on weight, has worse blood sugar and generally stops giving a fuck.
"Screw it. The other two are smart enough."
It's like making three pizzas. The first one gets all the best ingredients, arranged carefully in a perfect ratio across every slice. For the second one, you find that you've run out of cheese halfway through, and you kind of just throw everything on there. For the third, you shit on the pizza just to see how it turns out. If you're the youngest in your family, you are that third pizza.
Then, after you're born, it turns out that not only do your parents love your older siblings more than you, they also spend more of their household's available resources on them. There is simply less time, money and attention available to a family's youngest child.
In big families, parents cannot provide proper nutrition to their youngest children, presumably because after years of responsible child rearing, they decide that owning a feral scavenger might be a fun change of pace.
"Honey, I think I know how we can save some money on our grocery bills..."
It's for similar reasons that...
Anyone with an older brother or sister has shared this pain. No matter how hard you try, your older sibling always seems to come out ahead. Upon realizing that your parents actually went to that sibling's athletic events, hugged them and even gave them real meals rather than your two daily bowls of expired dog food, you decided that, if you hit the books hard enough, you could at least surpass your elders academically. Curing cancer will show them all!
Great science is driven by deep fear of inadequacy.
Nope, sorry. In a recent study analyzing over 240,000 subjects, researchers found that, on average, the eldest sibling scored three points higher on an IQ test than their younger kin. Three points may not seem like much, but it can be the difference between receiving a nice fat acceptance envelope from Yale, and having them send you a rejection letter nailed to a dead possum.
We've already explained how your older kin get the lion's share of your family's resources, but it turns out that they also get the best education during the crucial infant years. Before you and the other homewreckers came along, your eldest sibling secured your parents' undivided attention for however long they were Mom's #1. Logically, each subsequent child divides this attention, and you only wind up with half, or a third, or a quarter of the time and dedication that the golden child ever had.
Scientists think that this head-start leads to higher vocabulary and reasoning abilities, and because the younger children are increasingly faceless members of a growing litter, they never have a chance to develop the same brainpower. It's called the dilution hypothesis.
But there's more. As the family grows, older siblings begin to take on some of the responsibilities of their fed-up parents. This means often that they become makeshift tutors for their dumb-as-a-brick brothers and sisters. Ironically, because teaching something is the best way to learn it, this benefits them more than it does you.
By this logic, teachers are the most selfish people on the planet.
It may seem altruistic that they would act as your mentor, but what they're really doing is reinforcing the fact that you will never be better than them. Ever.