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6 Cards in this Set
- Front
- Back
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How many mass extinctions have there been in Earth's history, as far as we can tell by geological records?
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Five.
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Around the world, what event coincided with the disappearance of the "giant mammals"?
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The arrival of humans in the territory of the giant mammals.
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What factors have been attributed to the extinction of large mammals?
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Human activity:
Hunting practices Setting fire to the landscape to flush out prey |
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What is believed to be the main culprit in the recent widespread death of amphibians?
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A fungus belonging to a group called chytrids
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What was so remarkable about the chytrid?
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Chytrids had never been known to attack vertebrates before, so an entirely new genus had to be created to house this new group of fungi.
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What was the significance of the African clawed frog?
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In the 1930's, Lancelot Hogben discovered that females of the species laid eggs when injected with certain human hormones. This became a way to test for pregnancy and these frogs were exported all over the world. They are thought to be one of the origins of the amphibian-killing chytrids.
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