How dinosaur extinction helped grapes thrive: ancient seeds tell the story

Lithouva - the earliest fossil grape from the Western Hemisphere, ~60 million years old from Colombia. Top figure shows fossil accompanied with CT scan reconstruction. Bottom shows artist reconstruction. Credit: Fabiany Herrera, art by Pollyanna von Knorring.

If you’ve ever enjoyed a glass of wine or a handful of raisins, you might owe a thanks to the dinosaurs’ extinction.

Researchers have discovered ancient grape seeds that shed light on how grapes spread after the dinosaurs died out.

This fascinating study, published in Nature Plants, shows how the death of the dinosaurs may have paved the way for grapes to flourish.

Scientists found fossilized grape seeds in Colombia, Panama, and Peru, dating from 60 to 19 million years ago.

These are some of the oldest grape seeds ever found in the Western Hemisphere.

“These are the oldest grapes ever found in this part of the world, and they’re just a few million years younger than the oldest ones found elsewhere,” says Fabiany Herrera, the lead author of the study and an assistant curator at the Field Museum in Chicago.

“This discovery shows that grapes began to spread across the world after the dinosaurs went extinct.”

It’s rare for soft tissues like fruits to be preserved as fossils, so scientists usually study seeds, which fossilize more easily. The oldest known grape seed fossils were found in India and are about 66 million years old.

This timing is significant because it’s around when a massive asteroid hit Earth, causing a major extinction event that wiped out the dinosaurs and dramatically changed life on the planet.

“We often think about the dinosaurs, but this extinction event had a huge impact on plants too,” says Herrera. “The forests reset themselves, changing the types of plants that grew there.”

Herrera and his colleagues believe that the extinction of the dinosaurs helped reshape forests. “Large dinosaurs likely kept forests more open by knocking down trees,” says Mónica Carvalho, a co-author of the study. “Without the dinosaurs, forests became denser with more layers of trees.”

These new, dense forests created opportunities for plants like grapes. “In the fossil record, we start to see more plants that use vines to climb trees, like grapes, around this time,” says Herrera. The diversification of birds and mammals after the extinction may have also helped grapes by spreading their seeds.

In 2013, Herrera’s Ph.D. advisor, Steven Manchester, described the oldest known grape seed fossil from India. While no fossil grapes had been found in South America, Herrera suspected they existed. His persistence paid off in 2022, when he and Carvalho were conducting fieldwork in the Colombian Andes.

Carvalho spotted a fossil and exclaimed, “Fabiany, a grape!” The fossil, found in a 60-million-year-old rock, was the first South American grape fossil and one of the oldest in the world.

The tiny fossil seed was identified based on its shape, size, and other features. CT scans confirmed its identity. The team named the fossil Lithouva susmanii, or “Susman’s stone grape,” honoring Arthur T. Susman, a supporter of South American paleobotany.

Further fieldwork in South and Central America led to the discovery of nine new species of fossil grapes. These fossils, ranging from 60 to 19 million years old, tell the story of grapes spreading across the Western Hemisphere and enduring many extinctions and changes.

“The fossil record shows that grapes are a resilient group,” says Herrera. “They’ve suffered a lot of extinction in Central and South America but have adapted and survived elsewhere.”

Given today’s biodiversity crisis, studies like this are valuable for understanding how species adapt to major changes. “These little, humble seeds can tell us so much about the evolution of forests,” says Herrera.