The end of the dinosaurs gave way to the spread of the grapevine


The end of the dinosaurs 66 million years ago led to the spread of plants such as the grapevine. Fossil grapes ranging from 60 to 19 million years old have been discovered in Colombia, Panama and Peru.

One of the species included in the findings represents the oldest known example of grapevine plants in the Western Hemisphere, according to a study published in the journal Nature. NaturePlants.

“This is the oldest grape that has been found in this part of the world, and it is several million years younger than the oldest grape found on the other side of the planet,” he says. this statement Fabiani Herrera is associate curator of paleobotany at the Negaunee Center for Integrative Studies at the Field Museum in Chicago and lead author of the paper. “This discovery is important because it shows that after the extinction of the dinosaurs the grapes really started to spread around the world.”

Soft tissues like fruit rarely fossilize, so scientists’ understanding of ancient fruits often relies on seeds, which are more likely to fossilize. The oldest known grape seed fossils were found in India and are 66 million years old.

It’s no coincidence that grapes appeared in the fossil record 66 million years ago, around the time a huge asteroid hit Earth, causing a mass extinction event that changed the course of life on the planet. “We always think of animals, dinosaurs, because they suffered the most, but the extinction also had a big impact on plants,” Herrera says. “The forest was restored in a way that changed the composition of the plants.”

Herrera and his colleagues suggest that The extinction of dinosaurs may have helped change the forests. “Large animals such as dinosaurs are known to change the ecosystem around them. “We thought that if there were large dinosaurs roaming the forest, they would probably cut down the trees, effectively keeping the forests more open than they are today,” says Monica Carvalho. , co-author of the paper and assistant curator at the University of Michigan Museum of Paleontology. But without large dinosaurs to cut them down, some rainforests, including those in South America, became more populated. with layers of trees forming the undergrowth and canopy.

These new dense forests presented an opportunity. “Around this time in the fossil record, we started to see more plants that use vines to climb trees, like grapes,” Herrera says. The diversity of birds and mammals in the years after the mass extinction may have also helped the grape spread its seeds.

In 2013, Herrera’s thesis advisor and lead author of the new paper, Stephen Manchester, published a paper describing the oldest known grape seed fossil from India. Although fossil grapes had never been found in South America, Herrera suspected they might be there too.

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

But in 2022, Herrera and her co-author Mónica Carvalho were conducting field research in the Colombian Andes when they discovered a grape fossil in a 60-million-year-old rock, making it not only the first grape fossil in South America, but also one of the oldest grape fossils in world.

The fossil seed is tiny, but Herrera and Carvalho were able to identify it by its particular shape, size and other morphological characteristics. Returning to the lab, they performed a CT scan that showed his internal structure and confirmed his identity.

The team named the fossil Lithouva susmanii, “Susman’s stone grape,” after Arthur T. Susman, a proponent of South American paleobotany at the Field Museum. “This new species is also important because confirms the South American origin of the group in which the common grape vine Vitis developed.” says co-author Gregory Stull of the National Museum of Natural History.

The team conducted additional field work in South and Central America, and in the Nature Plants paper, Herrera and his co-authors ultimately described nine new species of fossil grape varieties from Colombia, Panama and Peru that existed between 60 and 19 million years ago. These fossilized seeds tell not only the story of the spread of grapes throughout the Western Hemisphere, but also the numerous extinctions and expansions that this grape family has endured. The fossils are only distant relatives of grapes native to the Western Hemisphere, and some of them, such as the two species of Leah, Today they are found only in the Eastern Hemisphere.

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