Very little of the food found at Thanksgiving dinner tables can credit their origin to the United States.
Carrots are native to Afghanistan, while potatoes and tomatoes came from South America, and even pumpkins originated from Mexico. So is there any fruit or vegetable that is commonly found in a holiday dish that has been here since the beginning?
For a long time, the answer that archeologists and anthropologists gave was no. The traditional theory was that Indians living in Mexico first collected gourds and planted their seeds for food roughly 8,000 years ago.
It was believed that over time the seeds and knowledge were passed along spreading throughout North America. Discoveries of gourd seeds and rinds dated to be around 8,000 years old reinforced this idea in the 1960s and 70s that all squashes and gourds came from Mexico.
Yet in the 1980s, excavations in Tennessee, Kentucky, Missouri and Illinois found the rinds and seeds of wild gourds at Native American sites that were 7,000 years old. Gourd remains found from sites 3,000 to 4,000 years old on the other hand did show signs of domestication.
This discovery caused researchers to question the theory that cucurbits (the genus of gourds) were introduced to eastern North America as domesticated plants since the 7,000-year-old seeds appeared to be wild.
With that question in mind, Smithsonian archeologist Bruce Smith and archeologist C. Wesley Cowan with the Cincinnati Museum of Natural History led an expedition into the Ozark Highlands of Arkansas and Missouri in 1990 to find the possible wild ancestor of modern day’s summer squash.
What they found was the “Johnny gourd” (Cucurbita pepo ozarkana) which has been known to farmers in western Kentucky for decades, but was simply assumed to be a ‘garden escape.’
While garden escapes are crop plants that have spread outside of fields and established wild populations, Smith and Cowan found that the gourds were thriving far from human establishments.
“In almost every stream or river we investigated, we found wild gourd vines climbing up into trees and bushes or stretching across gravel bar,” Smith told the Los Angeles Times.
After studying the life cycle and environment of the gourds found on their expedition, Smith and Cowan concluded that Cucurbita pepo ozarkana is indeed a wild, indigenous plant that has been long adapted to river flood-plain life.
Smith and Cowan also collected gourds from 20 different locations and brought them to Dr. Deena Decker-Walters and Dr. Terrence Walters who are experts on the taxonomy and evolution of the squashes at the Fairchild Tropical Garden in Miami, Florida, to conduct a detailed genetic analysis of the Ozark wild gourd.
They compared it to other wild gourds and domesticated pumpkins and squashes in family Cucurbita pepo. According to Decker-Walters, the Ozark wild gourd possesses the genetic pattern they expected the wild ancestor of the eastern North American squashes to have.
“The Ozark wild gourd has been crossbred, hybridized, fiddled within Europe and North American and other places around the world, resulting in the wide variety of summer squashes and ornamental gourds we have today – acorn, crookneck, zucchini, summer squash, ornamental gourds and others,” Smith told the Los Angeles Times.