When scientists find a new rock formation or fossil assemblage, how do they determine how old it is? The answer lies in the many varied methods of geologic dating. In this episode, we’ll discuss how we can sort the events in Earth history, how we calculate specific ages for ancient materials – including a deep-dive into radiometric dating! – and most importantly, how these many techniques support and complement each other.

In the news: gaze following, polar pterosaurs, pachycephalosaur heads, and giant marsupials.

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The Intro and Outro music is “On the Origin of Species” by Protodome.

Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0