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  • If you time-warped a few Pilgrims to your Thanksgiving table, they’d probably accuse

  • you of being a witch.

  • [YELLING]

  • But they’d recognize a lot of the food, just bigger, better, and tastier versions

  • of what they ate.

  • Many traditional Thanksgiving foods are scienced up versions of native New World species.

  • What may surprise you is that before DNA, genetics, or Europeans showed up, the original

  • residents of the Americas had already been molding these foods for thousands of years,

  • turning the wild and barely-edible into domesticated deliciousness.

  • [OPEN]

  • Despite the name, the turkey is from here.

  • Ben Franklin preferred the gobbler over the eagle for America’s national bird, it was

  • (in his words) “a true original Native of America.”

  • Today, most of us can’t tell a snood from a caruncle, but turkeys were hugely important

  • to many early American cultures.

  • In fact along with dogs, llamas, alpacas, and guinea pigs, turkeys are one of the few

  • domesticated animals native to the Americas.

  • Ancient trash dug up by archaeologists tells us about two thousand years ago a few Native

  • American cultures realized breeding birds in captivity is easier than chasing them through

  • the forest.

  • Luckily those birds pooped a lot, and old poop is one of an archaeologist’s favorite

  • things.

  • Fecal forensics can tell us a bunch of information about the animal that dropped that dung.

  • When scientists analyzed DNA from turkey coprolites found at archaeological sites in the American

  • Southwest, they found that a single turkey lineage was maintained in the area for like

  • a thousand years.

  • These native cultures were breeding and trading turkeys in a really sophisticated way long

  • before European contact.

  • Today’s turkeys don’t bear much resemblance to the rugged pioneer birds who waddled among

  • the Pilgrims and Native Americans.

  • This is the broad-breasted white, turkey of choice on modern farms, less bird, more ball-of-meat-and-feathers.

  • It’s been selectively bred to turn feed into meat, and it does that really well.

  • Modern turkeys can turn 2.5 pounds of bird food into a pound of bird and hit full size

  • in just five months.

  • Even our grandparents would be shocked at the size of today’s birds, since 1930 the

  • average weight of a turkey has doubled.

  • Farmers make bigger, meatier turkeys by crossing the biggest, meatiest turkeys in each generation

  • to amplify the gene variants for bigness and meatinessbut this only works to a point.

  • The birds get so big they can’t actually do the mating deed.

  • Unless farmers do it for them.

  • Today’s turkeys only exist because artificial insemination has let them break through the

  • barriers of natural selectionand gravity.

  • Ear’s another mutant from the Thanksgiving menu.

  • Get it?

  • EAR!

  • Too corny?

  • Tough crowd.

  • This is teosinte, a wild grass from Mexico and the genetic ancestor of corn, or maize.

  • The ancestor of your turkey was still a turkey, but ancient cornreally doesn’t look

  • worth the trouble.

  • We know early Americans first started farming and breeding teosinte about 9000 years ago,

  • but that’s not that long ago considering how different today’s butter-drenched sugar

  • missiles are from their ancestor.

  • Modern experiments on wild teosinte turned up some surprises: As few as 5 genetic changes,

  • in the right places, might have been enough to invent corn, or at least something that

  • looks like corn.

  • Once farmers had that basic corn template, they coaxed smaller, slower changes from thousands

  • of genes to get specific traits.

  • Today, we know genetic modification of corn is lessfarmers in the fieldand more

  • scientists in the lab”, but both are proof that evolution doesn’t always play

  • out as a slow, gradual process.

  • Small changes to single genes can have huge effects, especially if natural selection is

  • replaced by human hands.

  • There’s similar stories behind most other Thanksgiving foods:

  • How a starchy root from the mountains of Chile was mutated into the mighty potato, and its

  • tiny cousin the potato tot.

  • How tiny bitter squashes became sweet pumpkins, which were somehow then turned into this.

  • How a swamp fruit became delicious cranberry sauce, which somehow morphed into whatever

  • they put in those cans.

  • How the first people to cross the Bering Strait found a nut that wasn’t actually a nut,

  • and gave us the most delicious pie in the worldpronounced pec-ahn, not pee-can.

  • What ties these all together?

  • Every cross of meaty turkeys or sweet corn takes an organism’s genes and modifies them,

  • it’s just a question of scale.

  • Evenheritage”, “heirloom”, and other old-sounding varieties are mutant versions

  • of wild plants and animals, hacked by hungry humans to be richer, tastier, and easier to

  • grow.

  • Some of those humans wear lab coats, but some were here thousands of years before we ever

  • sat down at the table.

  • Let’s be thankful for all the people that made this meal possible.

  • Stay curious.

  • Fun fact about teosinte: those tough seeds evolved to pass through an animal’s digestive

  • system intact, so they could bedispersed”… corn might look different, but that’s one

  • trait corn kind of still carries today.

  • If you know what I’m saying.

  • You know, it’s never too early to start holiday shopping.

  • Might I suggest a stylish “I Did a Science” t-shirt?

  • Now available in ladiescut from our friends at DFTBA, just click up there, or check the

  • link in the description.

  • And if that’s not your style, I hear the gift of knowledge is perfect for any season.

If you time-warped a few Pilgrims to your Thanksgiving table, they’d probably accuse

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感恩節食品的驚人起源 (The Surprising Origin of Thanksgiving Foods)

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    Study English 發佈於 2021 年 01 月 14 日
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