A recent study revealed that humans began domesticating avocados as far back as 7,500 years ago in what is now Honduras, intentionally improving the trees by selectively planting for thicker skins and larger fruits, according to USA Today.
Researchers focused on a site in western Honduras called El Gigante, an elevated cave that people began to frequent 11,000 years ago. Over generations, inhabitants left behind piles of seeds, corn grains, agave leaves, and other plant remains. These trash heaps span the last 11,000 years and contain fragments of more than 20,000 plants such as avocados, bottle gourds, agave, beans, and squashes.
The team of anthropologists and evolutionary biologists analyzed 1,725 fossilized avocado samples recovered over many years from the site. They observed that both the seeds and the rinds of the avocado fruit changed over time. The avocado seeds grew larger, reaching apricot size in layers dating back about 4,500 years ago. Additionally, the rinds became thicker, making the fruits easier to store and transport while they matured and became edible.
Amber VanDerwarker, an expert in ancient plants and agriculture at the University of California, Santa Barbara, commented on the findings. "One of the reasons to want to cultivate a thick avocado skin is the ease of holding it," she said.
"We see the fruits getting larger and the rinds are getting thicker," she added.
The researchers suggest that these changes are indicative of domestication by humans, who preferred larger fruit and thicker skins. By comparing the sizes of the seeds and skins over time, the team was able to track how humans shaped the fruit. "Within a couple of thousand years, they were clearly managing their avocado trees," VanDerwarker noted.
The study provides the oldest example of avocado domestication known to date, with evidence suggesting it began as early as 7,565 to 7,265 years ago. This predates the arrival of more commonly studied plants like maize in the region. "When corn arrived, they already understood the whole notion of planting seeds and managing growth," VanDerwarker said.
The inhabitants of what is now Honduras included avocados in their diet at least 10,000 years ago, with carbon dating showing they were eating avocados as long as 11,000 years ago. Initially, they were likely foraging wild avocados, but over time, they began to manage and domesticate the trees. "These people literally domesticated their forests," VanDerwarker said.
Douglas Kennett, a professor of environmental archaeology at the University of California, Santa Barbara, highlighted the significance of human intervention in the survival of avocados. "Humans intervened at that point," he said, referring to the period after the mass extinction of megafauna at the end of the Pleistocene. These large animals, such as mammoths and giant sloths, had previously dispersed avocado seeds across Central and South America. With their disappearance around 12,500 years ago, avocados might have faced decline without human involvement.
The findings challenge the traditional view that the beginnings of farming in the Americas started with animals and cereal grains. Instead, the evidence indicates that early agriculture may have begun with the cultivation and management of fruit-bearing trees in the jungles, including avocados, palms, and soursops. This early tree cultivation primed the peoples of Central and South America to later grow field crops like corn. Ethnobotanists and archaeologists are discovering that the first agriculture in the Americas actually began with trees.
Today, avocados are a staple in many diets and have surged in popularity, particularly in the US. While avocados are grown in California and Florida, more than 90% consumed in the US come from Mexico. The most commonly eaten variety, the Hass avocado, is a cross between Mexican and Guatemalan avocado varieties.
"I think people have probably been eating guacamole for about 10,000 years," VanDerwarker said.
The article was written with the assistance of a news analysis system.