![]() ![]() But it could also cause cold snaps, as particulate matter blocks the sun. Such extreme volcanism would certainly result in higher temperatures, as greenhouse gases saturate the atmosphere. The culprit is likely a combination of climate changes. But the simple fact of global warming, he notes, “doesn’t really tell you anything about the kill mechanisms.” What actually laid waste to the biosphere? 'Hothouse Planet' “What you see at the surface is only part of it,” Renne says. Those eruptions would have released an enormous amount of carbon dioxide, and it’s possible that subterranean magma, as it ignited coal seams, added even more. Since then, more analysis has refined that chronology, bolstering the link between the most voluminous volcanism since complex life first emerged and the most profound die-off of all time. In the 1990s, Renne and his colleagues were the first to date the Siberian Traps, matching them almost perfectly to the fossil record for the extinction. They’re really just flows that creep over large areas.” “These eruptions are very, very different,” Renne says. They aren’t the product of some ancient Mount St. Altogether, the layers of magma cover more than half a million cubic miles - or enough to bury the entire world to a depth of around 20 feet. And, in contrast to many extinctions, most scientists agree on its main cause: “Volcanism has pretty clearly emerged as the robust answer,” says Paul Renne, a geophysicist at the University of California, Berkeley.Įvidence for this theory comes from the Siberian Traps in Russia, a vast field of lava flows left over from intense volcanic activity near the end of the Permian period. This cataclysm was by far the most desperate time for life on Earth. The extinction that wiped out the dinosaurs draws more attention, but it’s no match for the Permian, the third major mass extinction of the Big Five. ![]() They don’t call it the “Great Dying” for nothing - 95 percent of marine species and three-quarters of land species perished, as the largest volcanic eruptions in history fueled a devastating period of climate change that many researchers compare to global warming today. During the Permian mass extinction 250 million years ago, it almost caught up. Persia was eventually conquered by Alexander the Great in 334 B.C.E.From the moment life arose on our planet, death trailed close behind. Xerxes depleted the royal treasury with an unsuccessful campaign to invade Greece and continued with irresponsible spending upon returning home. The Persian Empire began to decline under the reign of Darius’s son, Xerxes. Darius also used the tribute money paid to him from each province to fund public works, such as roads and canals. He set up a system of provinces and governors, and a postal service that spanned the empire in order to establish widespread communication. Darius recognized that such a large area needed to be properly structured and organized in order to function efficiently. Cyrus also practiced religious and cultural tolerance toward conquered people.Ĭyrus’s relative Darius I (known as Darius the Great) took the throne after him and built the empire to its greatest height. He was known to spare the life of a defeated king so that the king could guide Cyrus in successfully ruling over the captives’ subjects. Cyrus was unlike other emperors because he showed mercy toward the cities and kingdoms he conquered. Eventually he was known as Cyrus the Great. From then on Cyrus was called the “ shah,” or king, of Persia. The Persian Empire emerged under the leadership of Cyrus II, who conquered the neighboring Median Empire ruled by his grandfather. At its height, it encompassed the areas of modern-day Iran, Egypt, Turkey, and parts of Afghanistan and Pakistan. The Persian Empire, also known as the Achaemenid Empire, lasted from approximately 559 B.C.E. ![]()
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