Not only fauna but also flora has been evolving since the Bing Bang. Like animals, today’s final shape of plants doesn’t resemble those of the past. For the first time, researchers managed to understand the primitive growth method trees employed originally. This finding highlights how much evolution changed the face of the Earth.
Science Lacked Comprehension of How Trees Were Able to Grow Tall in the Past
Around 393-359 million years ago, the Devonian Period was entering its last stage. This was when the evolution of trees and forests started to alter the atmosphere and environment on Earth.
Researchers started to study closely the oldest fossils of trees which belong to class Cladoxylopsida. Their construction is different from today’s trunks that are based on a single shaft.
Their system consisted of a ring formed by hundreds of strands of water-conducting cells that are known as xylem. These cells were greatly interconnected with one another. However, scientists couldn’t explain how trees were able to grow tall and form rich forests.
A multinational team of scientists from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, Cardiff University, and the State University of New York at Binghamton managed to gather new insights from this era. They discovered and analyzed 374 million years old tree trunks in Xinjiang, Northwest China.
Cladoxylopsids’ Original Growth Method Resorted to Controlled Internal Collapses
Based on these fossils, researchers learned that trees’ original growth method held more secrets. They were able to become tall by channeling a unique property. This enabled them to form a cylindrical foundation. The more they developed, the more these constructions collapsed in a controlled way under the weight. Therefore, as the diameter enlarged, the mass became denser.
Once the strand interconnections were torn apart, the xylem system received new capabilities of accommodation. This way, trees were capable of extending upwards and give birth to tall forests to host in their turn rich fauna.
However, these unique properties found no continuation in today’s world. The cladoxylopsids have no modern versions. The dawn of the Devonian period represented their disappearance as well.
Specialists believe that their extinction was a means to make way to the ancestors of modern flora, Archaeopteris. They were able to adapt better to the new environmental conditions.
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