How Many Mass Extinctions Have There Been?

From the creator

There have supposedly been five “mass extinctions” in Earth’s history, but the real story is more complex than that. LEARN MORE ************** To learn more about this topic, start your googling with these keywords: - Mass Extinction Event: a significant, global decrease in the diversity of life - "Big 5": The five biggest mass extinction events since the Cambrian explosion of Life 550 million years ago - Biodiversity Crisis: Like a mass extinction, a biodiversity crisis is a marked depletion in diversity in the fossil record. Some scientists prefer to call the late-Devonian extinction a "biodiversity crisis" because a lack of speciation contributed to the loss in diversity just as much as extinction did. - Diversity curve: A line chart that shows the diversity of life (usually by genera, but sometimes by species or family) over time - Lagerstatte: a deposit of sedimentary rock that contains a profound number of fossils, often with excellent preservation - Shareholder Quorum Subsampling: A statistical method that corrects for some of the biases in the fossil record, allowing scientists to generate more accurate diversity curves CREDITS ********* Script Writer: Emily Elert (twitter:@eelert) Script Editor: Kate Yoshida (twitter:@KateYoshida) Video Illustrator: Ever Salazar (twitter:@eversalazar) Video Director: Emily Elert (twitter:@eelert) With Contributions From: Henry Reich (twitter:@minutephysics), Alex Reich (twitter:@alexhreich), Peter Reich Music by: Nathaniel Schroed

Published 2016-01-21 · Watch on YouTube ↗
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