The Curious Science of Humans at War

By Mary Roach
Grunt By Mary Roach book cover
Find it on Bookshop


Mary Roach is the queen of infectious curiosity. In Grunt, she explores the science of supporting humans at war. No, not the explosive technology you might expect, but the less glamorous aspects of war: diarrhea, ducks, heat, sleep. You’ll learn all about how scientists fix the discomforts that soldiers face every day– experiences you have probably never thought about.

I’m interested in the parts no one makes movies about—not the killing but the keeping alive. Even if what people are being kept alive for is fighting and taking other lives.

Main Points

Along the fantastic journey through military science, we learn that America’s massive defense budget is behind many of our modern comforts, like scratch ‘n sniff stickers. Roach addressed many fascinating questions, some that I’ve never thought to ask, and some that had been lingering unanswered in the back of my mind. For instance, I’ve always wondered about why the Navy wears blue camo, which never made sense to me given that they’re usually on a ship, which obviously has people on it no matter how well they might camouflage. I was happy to receive humorous confirmation of its irrationality:

Camo print became so popular that eventually Navy personnel began clamoring for it. To the embarrassment of many, the current Navy working uniform is a blue camouflage print. Unsure whether perhaps I was missing the point, I asked a Navy commander about the rationale. He looked down at his trousers and sighed. “That’s so no one can see you if you fall overboard.”

Roach injects a touch of humor in all the right places (soldiers with diarrhea are referred to as “leaky SEALs”), while maintaining the utmost respect for all servicemembers.

Almost everyone I’ve met down here has been easygoing and upbeat, especially given how tired they must be. I am, to quote the Dole banana carton in the galley pantry, “hanging with a cool bunch.” If everyone in the world did a stint in the Navy, we wouldn’t need a Navy.

Even her outdated language is charming — at various points she calls herself a “goober” and a “doof”, just to remind you that what these people are doing is extraordinary and requires special skills such that a regular person looks silly next to them.

Take-Home Message

There are many chapters in here I have not mentioned, so you will still get some fun surprises when you pick up the book. If you consider yourself a curious person, or if you just like to know random facts, I highly recommend you read it. It’s very satisfying for the nerd in all of us.

Sometimes courage is nothing more than a willingness to think differently than those around you. In a culture of conformity, that’s braver than it sounds.

Want to read more? Find Grunt here: Bookshop

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