How the Death of Dinosaurs Led to the Flourishing of Grapes

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Grapes have been linked to the story of humanity for thousands of years, providing the foundation for Wine produced by our ancestors Thousands of years ago — but that might not have been the case if dinosaurs hadn't disappeared from the planet, according to new research.

When an asteroid struck Earth 66 million years ago, it wiped out the giant animals and set the stage for other creatures and plants to flourish in the aftermath.

Now, the discovery of fossilized grape seeds in Colombia, Panama and Peru, dating from 19 million to 60 million years ago, is shedding light on how this humble fruit established itself in Earth’s dense forests and eventually established a global presence. One of the newly discovered seeds is the oldest example of a grape family plant ever found in the Western Hemisphere, according to a study of the specimens published Monday in the journal Nature Communications. Nature plants.

“These are the oldest grapes ever found in this part of the world, and they are a few million years younger than the oldest grapes found on the other side of the planet,” said Fabiani Herrera, lead author of the study and assistant curator of paleobotany at the Field Museum’s Negaunee Center for Integrative Research in Chicago, in a statement. “This discovery is important because it shows that after the dinosaurs went extinct, grapes really started to spread around the world.”

Like the soft tissues of animals, true fruits do not preserve well in the fossil record. But seeds, which are likely to become fossils, could help scientists understand which plants existed at different stages of Earth’s history as they reconstruct the tree of life and establish origin stories.

The oldest grape seed fossils ever found were discovered in India and date back 66 million years, around the same time as the dinosaurs went extinct.

“We always think about animals, and dinosaurs, because they were the ones most affected, but the extinction event had a big impact on plants as well,” Herrera said. “The forest reset itself in a way that changed the composition of the plants.”

Stephen Manchester, Herrera’s doctoral supervisor and also a lead author of the new study, published research on grape fossils found in India. That research inspired Herrera to wonder where other grape seed fossils might be found, such as in South America, even though they have never been found there.

“Grapes have an extensive fossil record dating back about 50 million years, so I wanted to find grapes in South America, but it was like looking for a needle in a haystack,” Herrera said. “I’ve been searching for the oldest grapes in the Western Hemisphere since I was a college student.”

Herrera and study co-author Monica Carvalho, an assistant curator at the University of Michigan Museum of Paleontology, were doing fieldwork in the Colombian Andes in 2022 when Carvalho discovered a fossil. It turned out to be a 60-million-year-old grape seed fossil trapped in a rock, among the oldest in the world and the first ever found in South America.

“She looked at me and said, ‘Fabiani, grapes!’ And then I looked at him and said, ‘Oh my God.’ It was so exciting,” Herrera said.

Despite the fossil's small size, its shape, size and other characteristics helped the duo identify it as a grape seed. Once back in the lab, the researchers performed CT scans to study its internal structure and confirm their findings.

They named the newly discovered species Lithouva susmanii, or “Sussman's stone grape,” in honor of Arthur T. Sussman, a pioneer of South American paleobotany at the Field Museum.

“This new species is also important because it supports a South American origin for the group in which the common grape Vitis evolved,” said study co-author Gregory Stahl of the National Museum of Natural History.

The rocks were deposited in ancient lakes, rivers and coastal areas, Herrera said.

“To search for such tiny seeds, I split every available piece of rock in the field,” he said, adding that the difficult search “is the fun part of my job as a paleobotanist.”

Thanks to this discovery, the team conducted further fieldwork across South and Central America, and discovered nine new types of fossil grape seeds trapped in sedimentary rocks. By tracing the lineage of the ancient seeds to their modern grape counterparts, the team realized that something had enabled the plants to thrive and spread.

The team hypothesized that the extinction of the dinosaurs changed the entire structure of the forests.

“Large animals, like dinosaurs, are known to alter the ecosystems around them. We think that if there were large dinosaurs roaming the forest, they were likely cutting down trees, keeping the forests more open than they are today,” Carvalho said.

After the dinosaurs disappeared, tropical forests became covered with grasses, and layers of trees formed as an understory and canopy. These dense forests made it difficult for plants to get light, and they had to compete with each other for resources. The researchers said climbing plants had an advantage and used it to reach the canopy.

“In the fossil record, we start to see more plants that use vines to climb trees, like grapes, around this time,” Herrera said.

Meanwhile, as a variety of birds and mammals began to spread across the Earth after the dinosaurs disappeared, they likely also helped spread grape seeds.

The study of the seeds tells the story of the grape's spread, adaptation and extinction over thousands of years, and shows its ability to survive in other parts of the world despite its disappearance from Central and South America over time.

Many of the fossils are related to modern grapes, while others are related to distant relatives or grapes native to the Western Hemisphere. For example, some fossil species can be traced to grapes that are found only in Asia and Africa today, but it’s unclear why grapes became extinct in Central and South America, Herrera said.

“The new fossil species tell us about a turbulent and complex history,” he said. “We usually think of modern, diverse rainforests as a ‘museum’ model, where all the species accumulate over time. However, our study shows that extinction was a major force in the evolution of rainforests. We now need to determine what caused these extinctions over the past 60 million years.”

Herrera wants to look for other examples of fossil plants, such as sunflowers, orchids, and pineapples, to see if they existed in ancient tropical forests.

Studying the origins of plants and their past adaptations helps scientists understand how they coped with the climate crisis.

“I just hope that most living plant seeds will adapt quickly to the current climate crisis. The fossil record of seeds tells us that plants are resilient but could disappear completely from an entire continent,” Herrera said.