About 1.6 billion years ago, the community of small bright red plant life forms, while floating in the shallow pool of the antediluvian water, was engraved in stone until the end of time. Or at least until until a team of Swedish researchers dug their fossils in sedimentary rocks in Central India. The study, published this week in PloS Biology, suggests that this collection of ancient, recently analyzed fossils discovered several years ago, apparently, is a red algae. If this is true, then complex multicellular life evolved much earlier than previously thought, and the evolutionary family tree of life on Earth, perhaps in serious need of pruning.
The First watch of life on Earth probably formed 3.5 billion years ago, about a billion years after the formation of our planet. But when these simple single-celled organisms, classified as "prokaryotes" because of the lack of nucleus, evolved into multicellular, nuklearenergie forms, called eukaryotes, this issue is not yet resolved. The eukaryotic Alga is considered to be one of the oldest forms of complex life. And given the fact that the previous discovered fossils dated red algae 1.2 billion years ago, the new discovery could reduce the evolutionary time line by almost half a billion years.
Clear, red seaweed found in the fossilized plates of cyanobacteria, which is considered the first kislotoobrazoutei ispfargoni that emerged as the forerunners of algae and plants. (Though not all algae are considered "plants" in accordance with the current classification, they are considered plants because they use photosynthesis for energy production). Dissolving the surrounding rocks with acetic acid — conventional method applied during the excavation of fossils — authors of the new work found, apparently, two forms of red algae: tubular strain resembling segmented noodles, and more fleshy kind, consisting of layered collections of cells.
The Authors used a technique called synchrotron x-ray tomographic microscopy to build three-dimensional models of fossils to reveal internal cell structures that organisms probably used for energy production. To determine the age of fossils used in radioactive Dating. "The new fossils provide tangible evidence that the developed mnogoletnei, at least in plants, appeared much earlier than previously thought," says Stephan Bengtson, senior author of the new article and Emeritus Professor of paleozoology the Swedish Museum of natural history. "They assume that the timing of the appearance of the first eukaryotes may have radically reformed".
In the absence of DNA which does no such old samples it is impossible to confirm that the latest fossil remains from red algae. It recognizes and Bengtson. He also believes that the structures of the fossils have a strong resemblance to the structures of red algae.
Paul Strother, a biologist from Boston College who studies the evolution of algae and plants and who was not involved in the new study, disagrees. "If they are real, they still show no cell differentiation. All these cells are practically identical, their forms do not constitute a complex mnogoletnei," he said.
The Chairman of the Department of biology of the University of Wisconsin-eau Claire Wilson Taylor, also did not participate in the work, said that even if the new samples are, indeed, seaweed, search of origins, the origin of complex life takes a lot of time. "If red algae really evolved by this time, this implies a previous period of eukaryotic evolution of a certain length," he says. "But how long it lasted before the appearance of eukaryotes at around 1.6 billion years old, that's weird". Taylor explains that eukaryotes — in fact, all necroscopies life on Earth most likely came about when one of the prokaryotes took another and found symbiotic benefits in such a relationship. But the time it took to make this vital link was fixed in the evolutionary process, is unknown.
As noted Bengston, while red algae are not the direct precursor of the plant — that honor belongs to the ancestors of green algae — today, they are close to one common ancestor of all plants on Earth. If it is assumed that the new data is correct, the main question facing paleobotanists, is why it took another billion years to have a larger and more complex organisms.
Indeed, the development of higher plants and animals began only 500-600 million years ago. Underwater algae pop up on the blankets microbes gradually become known to us plants. Plants left on the coast, forming a new landscape that will include complex mushrooms and eventually land animals.
Bengtson hopes to further the study of early populations of algae to better determine where and when they occurred and why so long in the sea. Although the bifurcation of evolution, no doubt, will change — some to be routed, other reloaded — scientists to understand which of them will lead to a modern lineage of life on Earth.
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