This article describes a fossil that is interesting from both a biological and a geological perspective. Clearly, further research is needed.

This article describes a fossil that is interesting from both a biological and a geological perspective. Clearly, further research is needed.

Scientists find ‘Devil Toad’ fossil Discovery of bowling ball-sized frog raises ancient geography questions This artist rendering shows a Beelzebufo ampinga facing off against the largest known living Malagasy frog, Mantydactylus ampinga. A full-length pencil provide size perspective. AP By Lauran Neergaard updated 4:47 p.m. CT, Mon., Feb. 18, 2008 WASHINGTON – A frog the size of a bowling ball, with heavy armor and teeth, lived among dinosaurs millions of years ago — intimidating enough that scientists who unearthed its fossils dubbed the beast Beelzebufo, or Devil Toad. But its size — 10 pounds and 16 inches long — isn’t the only curiosity. Researchers discovered the creature’s bones in Madagascar. Yet it seems to be a close relative of normal-sized frogs who today live half a world away in South America , challenging assumptions about ancient geography. The discovery, led by paleontologist David Krause at New York’s Stony Brook University, was published Monday by the journal Proceedings of the National Academy of Sciences . “This frog, if it has the same habits as its living relatives in South America, was quite voracious,” Krause said. “It’s even conceivable that it could have taken down some hatchling dinosaurs.” Krause began finding fragments of abnormally large frog bones in Madagascar, off the coast of Africa, in 1993. They dated back to the late Cretaceous period, roughly 70 million years ago, in an area where Krause also was finding dinosaur and crocodile fossils. But only recently did Krause’s team assemble enough frog bones to piece together what the creature would have looked like, and weighed. The largest living frog, the Goliath frog of West Africa, can reach 7 pounds. But Krause teamed with fossil frog experts from University College London to determine that Beelzebufo isn’t related to other African frogs. It seems to be a relative of South American horned frogs, known scientifically as Ceratophrys. Popular as pets, they’re sometimes called pacman frogs for their huge mouths. Like those modern frogs, Beelzebufo had a wide mouth and powerful jaws, plus teeth. Skull bones were extremely thick, with ridges and grooves characteristic of some type of armor or protective shield. The name comes from the Greek word for devil, Beelzebub, and Latin for toad, bufo (pronounced boo-foe). The family link raises a paleontology puzzle: Standard theory for how the continents drifted apart show what is now Madagascar would have been long separated by ocean from South America during Beelzebufo’s time. And frogs can’t survive long in salt water, Krause noted. He contends the giant frog provides evidence for competing theories that some bridge still connected the land masses that late in time, perhaps via an Antarctica that was much warmer than today.

1. Read Chapter 18: Plate Tectonics and the article: Chapter 18 – Devil Toad.pdf
2. Answer the following question:

This article describes a fossil that is interesting from both a biological and a geological perspective. Clearly, further research is needed. What research results might confirm or refute the claims made in this article?

3. Post your essay by starting a new thread.
4. Please read all other posting and reply to at least 1 other person’s post. Your post should comply with requirements posted in the Discussion Questions Rubric and be at least 250 words

4 hours ago

Hi 

this is the second Discussion paper,

An Icelandic Volcano Reveals Secrets of Its Eruption By HENRY FOUNTAIN JULY 14, 2016 A plane flying over the Bardarbunga volcano spewing lava and smoke on Sep. 14, 2014. Credit Bernard Meric/Agence France-Presse — Getty Images Some of the world’s most cataclysmic volcanic eruptions are associated with the collapse of a caldera, a depression in the top of the volcano that forms and deepens as a reservoir of magma below it empties out. The two largest of the 20th century — Pinatubo in 1991 in the Philippines and Novarupta in Alaska that formed the spectacular Valley of Ten Thousand Smokes in 1912 — both blew their tops this way. Caldera collapses are rare, and when they do occur they usually happen quickly, in hours or a few days. But when Bardarbunga, a large volcano under an ice cap in central Iceland, erupted in August 2014, the caldera sank and collapsed gradually over the course of the six-month eruption. That gave scientists a unique opportunity to study it. In a report published Thursday in the journal Science, volcanologists reveal that the sinking caldera actually helped drive the eruption, by keeping pressure on the magma chamber as the hot rock flowed out. “We are talking about a hydraulic system,” said Magnus T. Gudmundsson, a researcher at the University of Iceland and lead author of the paper. The caldera, he said, pushed down on the reservoir of magma, which flowed nearly 30 miles through a fracture in the volcano before emerging at the Holuhraun lava field. Because the caldera collapse happened under the Vatnajokull ice cap, which is about 1,500 feet thick on average, Dr. Gudmundsson and his colleagues had to study it indirectly using seismometers, radar and other instruments. They also placed GPS sensors on top of the ice, which enabled them to gauge the collapse of the caldera because the ice followed it as it sank. The caldera is roughly oval in shape, covering about 40 square miles, making the collapse the largest ever monitored. Over the course of the eruption it sank about 200 feet. Every week, we’ll bring you stories that capture the wonders of the human body, nature and the cosmos. Dr. Gudmundsson said the research showed that the eruption started when pressure increased within the magma chamber, which is at a depth of about seven miles. The caldera collapse began about five days later, when an estimated 12 percent to 20 percent of the magma had already left the chamber. If the collapse had not started, Dr. Gudmundsson said, the eruption might have ended at that point because the loss of all that magma had reduced the pressure in the chamber. But the collapse put new pressure on the chamber, and the flow of lava continued. The caldera, he said, “is like a piston pushing down on a body of fluid, and there is a pipe going from this container of fluid sideways to the surface.” John Stix, a volcanologist at McGill University in Montreal, said the Bardarbunga findings were fascinating for what they showed about the mechanics of the collapse. “One would think that calderas don’t collapse like pistons,” he said. “But effectively that’s what’s happening.” He said the study would help scientists better understand what drives extremely large eruptions like Tambora in what is now Indonesia, which led to what became known as the “year without a summer” when it erupted in 1815. Dr. Gudmundsson noted that scientists did not notice that the Bardarbunga caldera was collapsing until about two weeks after it started. That would not happen today, he said, thanks to this research, which identified the kinds of seismic signals that indicate the start of a collapse. “That’s very important to know,” Dr. Gudmundsson added, “because not all collapses are as gradual and well behaved as this one.” For instance, if Yellowstone were to erupt again it would no doubt involve a collapsing caldera and be far more catastrophic than the one observed in Iceland. Despite some of the hysteria about Yellowstone, which last erupted 640,000 years ago, the odds of another eruption happening anytime soon are vanishingly small

1. Read Chapter 19: Building Earth’s Surface and the article: Chapter 19 – Icelandic Volcano.pdf
2. Answer the following question:

Describe the type of volcano that is being studied in this article. How does it behave? What extinct (hopefully!) volcano closer to home might erupt the same way?

3. Post your essay by starting a new thread.
4. Please read all other posting and reply to at least 1 other person’s post. Your post should comply with requirements posted in the Discussion Questions Rubric and be at least 250 WORDS.

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