the earth

Description

Hank takes us on a trip through time to revisit the 5 major mass extinction events that have impacted species over the Earth's history, and leaves us with some thoughts about what could possibly be the sixth event - the one caused by human activities. Like SciShow on Facebook: http://www.facebook.com/scishow Follow SciShow on Twitter: http://www.twitter.com/scishow References for this episode can be found in the Google document here: http://bit.ly/KOHsM5 extinction, mass extinction, scishow, science, biology, climate change, species, great dying, geological time scale, co2, temperature change, extinction rate, time machine, ordovician-silurian, die-off, glacier, glacial, gondwana, pangea, gamma ray burst, hypernova, ozone layer, extinction pulse, asteroid impact, supervolcano, late devonian extinctions, permian-triassic, dinosaur, cretaceous-tertiary, k-t, human impact