Child Development

The Science Behind Kids’ Obsession With Trains

It’s more than just Thomas the Tank Engine.

by Mark Oliver
Originally Published: 
A girl playing with toy trains on the floor.

It’s something that happens to pretty much every boy on earth, usually when they’re about 3-years-old: They’ll wake up one morning and decide that trains are, officially, the coolest thing in the world. For the next year, they will decree that every shirt must have a train on it, every tool must become a track, and the name of Thomas the Tank Engine must be spoken with the reverence due to a god. They will be loco for locomotives.

And if it isn’t trains, their obsession will revolve around cars, trucks, or anything with a big engine and wheels, really. It almost seems like boys are somehow biologically drawn toward fast things with wheels. And, well, it’s because they are. Your child’s love of choo-choos serves an important purpose — a major enough one that, if your kid’s not already obsessed with trains, you just might want to get a steam engine in their hands.

Biology Plays A Big Part

For a long time, the prevailing thought was that boys loved trains because society tells them to love trains. But it seems like biology has a lot to do with it too.

Here’s why: Little human boys aren’t the only ones drawn to things that roll — little monkey boys are, too. In 2014, a group of scientists gave both traditional ‘boy’ and ‘girl’ toys to a group of monkeys to see what they’d choose. The male monkeys, they found, gravitated toward cars and balls, while the girls played with pots and dolls. And that wasn’t a fluke — the experiment’s been reproduced twice since, with the same result both times.

The reason is testosterone. Another study sat baby boys in front of cars and balls. The higher the baby’s testosterone, they found, the more time the baby spent staring at things that roll.

Of course, many girls like trains. But if your little girl gravitates toward trains, there’s a good chance she has more testosterone than average. That’s not a bad thing. In fact, if your little girl doesn’t like trains, you might just want to get her into them. Because…

Rolling Taps Into An Evolutionary Need

There’s a reason boys are built this way. In fact, if little boys didn’t love trains, humanity probably would have gone extinct thousands of years ago.

The obsession over balls and wheels helps kids understand a lot of things, the most important of which — from an evolutionary perspective — is how things rotate. Playing with a ball helps a child understand that things are 3-dimensional, and this in turn improves their spatial reasoning.

That’s a big deal if you’re a monkey, because this helps them find food when they’re hunting and helps them survive when a jaguar pounces in the jungle. If a monkey doesn’t play with balls and wheels, there’s a good chance he’ll end up being pooped out of some predator.

All That Chugging Gives The Brain A Serious Workout

These days, you don’t have to worry about jaguar attacks. But that doesn’t mean those spatial reasoning skills are useless. Far from it, because they improve those all-hallowed STEM skills. Plus, there’s a direct correlation between spatial reasoning and SAT math scores. So when your kids are playing with a ball or a train, they’re actually improving the basic ability that’s going to get them a scholarship to a good college.

That doesn’t mean you can just play with trains until you’re 18 and get into MIT, but it’s a good first step.

Girls Should Play With Trains As Often As Possible

The problem with evolution is that we don’t live in the jungle anymore. Spatial reasoning was more useful for boys when they were the ones hunting and fighting predators. Today, however, it’s a skill all genders need.

Some girls are naturally drawn toward wheels, but most aren’t — and that might be a bigger problem than you realize. Remember that study that said spatial thinking improves math scores? Although the researchers only found a small correlation for boys, they found a huge one for girls.

If a girl gets into trains and balls at a young age, it’ll have an even bigger impact on her STEM success. Who knew that train set would produce such dividends?

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