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fandomhigh2018-06-12 01:16 am
livingartifact) wrote in fandomhigh2018-06-12 01:16 am
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Earth Zoology -- Pre-History Edition, Tuesday, Period 2
The Danger Shop was back above water today, in a sandy sort of environment around a broad, very shallow river. There were a few leafy ferns scattered about, but for the most part, the plant-life consisted of tall thin trees with clusters or narrow leaves at the very tops.
"Welcome back," Jenkins greeted. "Last week, we visited the Cambrian period, the earliest period of the paleozoic era — a name that literally means 'old animal'. Today we're in the Permian, the last period of that era, a time of great and catastrophic change with regards to Earth animals.
"Perhaps the most famous denizen of this period was this fellow coming along here, the dimetrodon." A large, almost crocodilian creature trundled along towards the water, the enormous sail along its back reaching to nearly Jenkins' shoulder. "Though dimetrodon is often grouped together with the famously charismatic dinosaurs — we met a few representatives of that group a few weeks back — he actually predates those giant reptiles by 40 million years. In fact, dimetrodon belongs to a group known as the synapsids, many of which were precursors to early mammals. Large species of dimetrodon, like our friend here, would likely have been the apex predator of their age — that is, the creature that feeds upon others, but is not fed upon himself. Explanations for the dramatic sail along his back differ, of course. Many postulate that it would have been used for thermoregulation, the large surface area suitable for both absorbing and releasing heat. Others believe it was primarily decorative in nature — though that may well be a fancy way of saying 'we have no idea what this was for'." Jenkins gave the students a small, irreverent shrug. "Scientists and academics are very good at finding fancy ways around saying 'I don't know'.
"The dimetrodon lived primarily in the early Permian, between 295 and 272 million years ago, which may perhaps be considered somewhat lucky for him, as it means he was not around for the end of the period — and of the era — a time colloquially referred to as the Great Dying. Not a time period I believe any of us would enjoy being in. Beginning around 252 million years ago, something happened. Something about which we know very little. Some believe it may have been an asteroid strike." A flaming fireball streaked across the sky above the students, coming to earth somewhere beyond the horizon. "Meteor strikes are a favorite theory when it comes to mass extinction events," Jenkins continued, "as a large impact from space can flatten, burn, and otherwise destroy large swathes of land, throwing many millions of tons of matter into the air." The ground shook as the sky lit up bright white from a massive explosion, fading to an angry red. A shockwave blew through, flattening all the strange trees and scouring the river and landscape alike, though it did little more than ruffle the students' clothes, hair, or skin. A dense cloud of smoke and debris covered the sky, blotting out the holographic sun's light almost completely. "The impact itself can kill millions in an instant," Jenkins said. "But the resulting air pollution does far more damage. The sun may be obscured for months, if not years, causing catastrophic changes in temperature and weather patterns, spelling doom even on the other side of the globe. Scientists have identified a number of impact craters left behind by such meteors, including one they believe spelled the dinosaurs' doom at the end of the cretaceous period, 65 million years ago. That event brought on the extinction of as much as 75% of all life on Earth, and yet it does not have the distinction of being called 'the Great Dying'. As yet, scientists have not found a crater that may explain the end of the Permian, which saw the end of 70% of land-based life and 96% of that in the seas. It took more than 10 million years for Earth to redevelop the biodiversity lost — to date, it is the single largest extinction event known in Earth's history.
"But that won't happen for a little while yet," Jenkins said, as the sky cleared, the plants regrew from the ground, and the dimetrodon crept cautiously back out of the underbrush, eying the sky warily. "Our friend here misses that event by a good 20 million years. He only needs to worry about the usual things: finding food, water, and shelter, and avoiding the local proto-cockroaches."
"Welcome back," Jenkins greeted. "Last week, we visited the Cambrian period, the earliest period of the paleozoic era — a name that literally means 'old animal'. Today we're in the Permian, the last period of that era, a time of great and catastrophic change with regards to Earth animals.
"Perhaps the most famous denizen of this period was this fellow coming along here, the dimetrodon." A large, almost crocodilian creature trundled along towards the water, the enormous sail along its back reaching to nearly Jenkins' shoulder. "Though dimetrodon is often grouped together with the famously charismatic dinosaurs — we met a few representatives of that group a few weeks back — he actually predates those giant reptiles by 40 million years. In fact, dimetrodon belongs to a group known as the synapsids, many of which were precursors to early mammals. Large species of dimetrodon, like our friend here, would likely have been the apex predator of their age — that is, the creature that feeds upon others, but is not fed upon himself. Explanations for the dramatic sail along his back differ, of course. Many postulate that it would have been used for thermoregulation, the large surface area suitable for both absorbing and releasing heat. Others believe it was primarily decorative in nature — though that may well be a fancy way of saying 'we have no idea what this was for'." Jenkins gave the students a small, irreverent shrug. "Scientists and academics are very good at finding fancy ways around saying 'I don't know'.
"The dimetrodon lived primarily in the early Permian, between 295 and 272 million years ago, which may perhaps be considered somewhat lucky for him, as it means he was not around for the end of the period — and of the era — a time colloquially referred to as the Great Dying. Not a time period I believe any of us would enjoy being in. Beginning around 252 million years ago, something happened. Something about which we know very little. Some believe it may have been an asteroid strike." A flaming fireball streaked across the sky above the students, coming to earth somewhere beyond the horizon. "Meteor strikes are a favorite theory when it comes to mass extinction events," Jenkins continued, "as a large impact from space can flatten, burn, and otherwise destroy large swathes of land, throwing many millions of tons of matter into the air." The ground shook as the sky lit up bright white from a massive explosion, fading to an angry red. A shockwave blew through, flattening all the strange trees and scouring the river and landscape alike, though it did little more than ruffle the students' clothes, hair, or skin. A dense cloud of smoke and debris covered the sky, blotting out the holographic sun's light almost completely. "The impact itself can kill millions in an instant," Jenkins said. "But the resulting air pollution does far more damage. The sun may be obscured for months, if not years, causing catastrophic changes in temperature and weather patterns, spelling doom even on the other side of the globe. Scientists have identified a number of impact craters left behind by such meteors, including one they believe spelled the dinosaurs' doom at the end of the cretaceous period, 65 million years ago. That event brought on the extinction of as much as 75% of all life on Earth, and yet it does not have the distinction of being called 'the Great Dying'. As yet, scientists have not found a crater that may explain the end of the Permian, which saw the end of 70% of land-based life and 96% of that in the seas. It took more than 10 million years for Earth to redevelop the biodiversity lost — to date, it is the single largest extinction event known in Earth's history.
"But that won't happen for a little while yet," Jenkins said, as the sky cleared, the plants regrew from the ground, and the dimetrodon crept cautiously back out of the underbrush, eying the sky warily. "Our friend here misses that event by a good 20 million years. He only needs to worry about the usual things: finding food, water, and shelter, and avoiding the local proto-cockroaches."
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