In July 1846, 85 people became members of the Donner Party with a single ill-fated choice: They turned left at a crossroads that they believed would trim three weeks from their trek to California. Instead, it added four, putting them at the Sierra Nevada in a year where winter came atypically early. In a choose-your-own-adventure-style piece for Wired, Cody Cassidy looks at the subsequent choices the party had to make—from the perspective of which ones you should make had you happened to be a part of the group. Your first big decision: When on Nov. 1 you reach the snow-filled Truckee Pass, which your oxen and wagons cannot traverse, do you abandon them and make way for California on foot or retreat to cabins at nearby Truckee Lake? The experts are split, writes Cassidy.
One thinks you'd make it to California; another says the month-long snowshoeing journey would be deadly. "So play it safe," writes Cassidy. Retreat. But with the knowledge the Donner Party didn't have: Unlike Midwestern peaks that open once the weather clears, there's no getting out until winter is over. Once you're at the cabins, hope you're not "a twentysomething single man in peak physical shape." If you are, ta-ta! As Cassidy explains, you're in trouble because your metabolism is high (doubly so if you're doing the hard work for the group) and your low bodyfat is a liability. Your best bet: Put your metabolism on ice by essentially not moving; one party member who was injured and bedridden survived longer than most of the men his age. But what you really need to do to survive is what some of the party did: resort to cannibalism. If this idea makes you squirm, read the full piece, which outlines how our opposition to it is cultural rather than Darwinian. (Read more Longform stories.)