Homehttps://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/Sciencehttps://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/Fossils unexpectedly discovered in the Jordan have changed the paradigm of plant evolution – Science and Health
Fossils unexpectedly discovered in the Jordan have changed the paradigm of plant evolution – Science and Health
A quarter billion years ago, earth life almost died. Like continents that have collided and formed a single mass land mass – the supercontinent of Pangea – the global climate has changed. It got cooler, especially inside. Around 96 percent of all species are thronging the seas and 70 percent of the earth's animals died off in what became known as the Great Permian Extinction. Nails and mosques covering the land sprout, although some survived, and still do, in their pockets.
Seed plants began to develop during the Devonian period, before Permian. But with the amazement of the paleo set, the sediment from the Permian period found in Jordan, through the Dead Sea in all areas, shows that if any, during the wasted time the new groups of seed plants are emerging; Three of them, in fact, one is the most famous pine. The other two later died.
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Plants and the Permian extinction
Permian Extinction is believed to have reached nearly 100,000 years, and has been the most severe event of extinction the planet is known. Most paleontologists agree with that. They do not agree with much, as what has caused it, though recent thoughts are less oriented towards a single event such as a comet effect, and more than the problems with pulses, including the fact that the creation of the supercontinent led to the unique climate.
We are not clear how many plant species their producers achieved during the Permian Extinction.
"Some estimates say 70 to 80 percent, but I do not know how reliable these numbers are," Prof. Hans Kerp of Munster University, a coauthor of a paper on Permian Extinction with Abdalla Abu Hamad, William A. DiMichele and Benjamin Bomfleur, told Haaretz.
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Plants in tropical regions seem to have destroyed, though in the far north (the boreal realm), the impact is more severe.
No group of dead trees has disappeared since the global climate has changed from a greenhouse world in Permian to a hothouse world in Triassic (the first Mesozoic era), says Kerp. Nails and mosques survived in one place, it seems to be higher latitudes where the effects of major events on extinction are often worse.
Growth of Gymnosperm seed in Triassic can be happy; among other things, they have internal vascular systems for water transport, so they are better adapted to cradles that have become commonplace. Surprise is the quest for gymnosperm development in the Permian era in a tropical setting that features time. The sediments from Permian are almost no fossils, says Kerp.
The climate on the Jordanian coast of about a century ago was monsoonal, with a long dry season and a short rainy season, says Kerp. "This is indicated by the presence of fossil soils, often with turbid layers and called iron planks, often formed in regions with this climate."
The typical Permian plants of ferns, giant horsetails, mosses and their ilk require constant humidity to survive, so they can not work well in this environment. But the very environmental stresses – the seasonality itself, wet winter, long dry summer – can be driven by plant evolution, says team, Kerp, Abu Hamad, DiMichele and Bomfleur.
Energetic environments that are prone to chaos, such as flash floods, landslides and similar forces are the forms of life to adapt and prosper, or die, the score of Kerp.
In short, the findings indicate that tropical drought habitats such as those encountered in the Jordan serve as evolutionary cradles for early plant diversity.
One of the plants found in the Permian fields of Jordan is nothing but the pine trees of the pine, the Podocarpaceae. It appears that they have begun to grow within a quarter of a century ago – and survived the great wipeout of Permian, say scientists after unexpected search of fossil twigs from these trees on the rocks of the Jordan .
The other two groups took the lead and then survived the destruction of Permian, but eventually died. One is the Corystospermaceae, a group of seed plants that lost about 150 million years ago. The other is Bennettitales, a "unique breed of dead seed plants with flowers like reproductive organs," explains Dr. Christina Heimken of Westfalische Wilhelms-Universitat Munster.
The truth says, Heimkin says paleobotanists know that the Corystospermaceae grow in Permian, and where the Jordan is now, in about ten years. They found the leaves. Now they also find the nature of the reproductive organs in this group. Mazal tov .
The discovery of the Jordanian cache of Permian fossils is even more impressive because it is not the type of place that is prone to sedimentation in any case, they are not the first seed plants, but new groups of seed plants will be dominant during the Mesozoic period.
"Perhaps Jordan is not the site where these plants grow can occur anywhere where those conditions exist, that is, a terrestrial region in the equatorial region with periodic dry climate, "says Kerp. "But the floras from the Jordan are unique, because there are no similar floras known today. They are very good and they are very large. Species are preserved (with leaves up to 60 centimeters long), and last but not least, there is good material protection with superbly preserved cuticles. These are the best preserved cuticles I have seen in my nearly 40 years of long career. "