2024-07-03 10:41:18
“These are the oldest grapes ever found in this part of the world, and they’re only a few million years younger than the oldest grapes ever found on the other side of the planet.” says the co-author of the study and Fabiany Herrera, assistant curator of paleobotany at the Field Museum Negaunee Center for Integrative Research (USA). “This discovery is important because it shows that after the extinction of the dinosaurs, grapes really began to spread around the world.”
Forest restoration
Usually, soft tissues – such as fruiting bodies – do not survive as fossils. Therefore, paleobotanists usually study ancient seeds – because they are more likely to remain fossilized. The oldest known grape seeds are approximately 66 million years old. years old – meaning they are from around the time when a huge asteroid hit the Earth, causing the mass extinction. It wasn’t just the dinosaurs that were wiped out and about 95 percent animal species on Earth, but also forests – finally the composition of the planet’s plants changed. The research team hypothesizes that the extinction of the dinosaurs may have helped change the forests.
“Large animals like dinosaurs are known to change the ecosystems around them,” says study co-author Mónica Carvalho, an assistant professor at the Museum of Paleontology at the University of Michigan (USA). “We think that if large dinosaurs roamed the forests, they likely destroyed the trees, effectively keeping the forests sparser than they are today.”
But in some rainforests, including those of present-day South America, the forests became denser after the giant dinosaurs left. Layers of trees eventually formed a canopy, and these new dense forests became very favorable for some plants.
“We’re starting to see more plants in the fossil record that are creepers, like grapes,” says Herrera.
Later, diversifying species of birds and mammals may also have helped the grapes by dispersing their seeds. in 2013 in the study conducted described the oldest known grape fossils found in India. At that time, grape seeds had not yet been found in South America, but F. Herrera already suspected that they might be there as well.
“The fossil record of grapes begins about 50 million years ago. years, so I wanted to find them in South America – but it was like looking for a needle in a haystack, – says the researcher. “I’ve been looking for the oldest grapes in this part of the world since I was a student.”
Fossilized seed
2022 m. F. Herrera ir M. Carvalho conducted field research in the Colombian Andes. Ms. Carvalho’s eye was caught by a fossil that turned out to be 60 million years old. the remains of a year-old grape seed. Not only was it the first South American grape fossil ever found, it was also one of the oldest in the world.
Despite being very small, the team was able to identify the seed based on its shape, size and other physical characteristics. They also carried out CT scans in the laboratory – which showed the internal structure of the find. Scientists named the fossil Lithouva susmanii – Susman’s stone grape -, in honor of Arthur T. Susman, curator of South American paleobotany at the Field Museum.
“This new species is also important because it confirms the origin of the South American group where the common Vitis grape species evolved,” said study co-author Gregory Stull of the US National Museum of Natural History.
Additional fieldwork in South and Central America resulted in the description of nine new fossil grape species from Colombia, Panama, and Peru. These fossil grapes are distant relatives of grapes growing in the Western Hemisphere. Some of these species, including two Lee a species found today only in the Eastern Hemisphere. Their position in the grapevine family tree suggests that their evolutionary path has been quite turbulent.
“The fossil record shows that grapes are a very resistant species,” says F. Herrera. “This is a group that has experienced many extinctions in the Central and South American region, but has been able to adapt and survive in other parts of the world.”
Adapted from Popular Science.
2024-07-03 10:41:18