named Arasemenia triaa new specimen from the Wutong Formation in China's Anhui Province, dates to the Famennian period of the Late Devonian, making it the second oldest known winged seed.
Many plants require seeds to reproduce. Seeds come in all shapes and sizes and often have additional features that help them disperse throughout the environment.
For example, some seeds develop wings from the seed coat as the outer layer. This is similar to the fruit of the plane tree, which has two wings that help it glide on the wind.
The first seeds are thought to have evolved during the Famennian period, between 372 and 359 million years ago.
According to the fossil record, almost all of these seeds were surrounded by additional protective structures known as couples and were wingless.
To date, only two groups of Famennia seeds have been reported to have wings or wing-like structures, and one group lacked couples.
“The oldest known plant seeds date back to the late Devonian period,” said Professor Deming Wang of Peking University.
“This period marks an important evolutionary milestone in plant history, as it transitioned from spore-based reproduction like ferns and mosses to seed-based reproduction.”
“However, little is known about wind dispersal of seeds during this period, as most fossils lack wings and are usually surrounded by a protective copple.”
Professor Wang and colleagues examined fossils of Famennian seed plants collected in China's Anhui province.
assigned to a new genus and species; Arasemenia triathe seeds are about 2.5-3.3 cm long and, unlike most other seeds of this era, clearly lack a cupple.
“In fact, this is one of the oldest known records of coppleless seeds, 40 million years earlier than previously thought,” the paleontologists said.
“Each seed is covered by a layer of integument, or seed coat, which radiates outward to form three wing-like leaves.”
“These wings tapered toward the tip and curved outward, creating a wide, flat structure that helped the seeds catch the wind.”
The researchers then compared Arasemenia tria Other known winged seeds from the Late Devonian: Warstenia and guasia.
Both of these seeds have four wings — guasiais wide and flat; WarsteniaIt's short and straight.
Scientists performed quantitative mathematical analysis to determine which seeds are most effective for wind dispersal.
This reveals that it has an odd number of wings, as follows: Arasemenia triaa more stable and high rotation speed is obtained when the seeds descend from the branches, and the seeds can catch the wind more effectively and disperse further from the parent plant.
“Our findings are Arasemenia tria This further deepens our knowledge about the origins of wind-driven dispersal strategies in early land plants,” said Dr. Pu Fan, a researcher at the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences.
“When combined with previous knowledge, guasia and WarsteiniaWe conclude that winged seeds as a result of integument elongation emerged as the first form of wind dispersal strategy in the Late Devonian, prior to other methods such as parachutes and plumes. ”
“The three-winged seed found in” Arasemenia tria “During the late Devonian period, double-winged seeds would have appeared in the Carboniferous period, and single-winged seeds would have appeared in the Permian period,” Professor Wang added.
of study Published in a magazine e-life.
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Deming Wang others. 2024. Arasemeniathe earliest ovule with three wings and no cup. e-life 13:RP92962;doi: 10.7554/eLife.92962.3
Source: www.sci.news
