RPTM Podcast Episode One: Precambrian, Paleozoic, Mesozoic, and Cenozoic Eras

Before we get started, we need to mention rule #1 for understanding history: Historians are detectives. Much like Batman or Sherlock H​olmes, historian look at the crime scene (in this case, the historical event) look for clues (in this case, books or archaeological sites), interview witnesses (in this case, secondary or primary sources) and interpret the findings to determine what happened. Much like an actual crime scene, the investigator must rely on what they have in front of them. Missing pieces always happen, but it's the goal of the historian to fill in the blank spaces with what his or her 'gut" tells them. Or they go to their utility belt of previous knowledge to help determine the most likely outcomes. This becomes rather difficult the further we get from the time frame of the crime, or what is referred to as a "cold case." Scents get thrown off; memory gets muddled. The picture becomes murkier as time slips from our grasp.

Why do I mention this? Remember that as we dive into the world of "pre-history" we don't have all the answers, and never will. But don't worry- I'm Batman.

To start looking at the history of the United States, we have to go back. I mean, really go back. (That's it. Keep going…)

HIGHLIGHTS

• The Earth is estimated to be approximately 4.6 billion years old—an age obtained by dating meteorites.
• The Precambrian covers almost 90% of the entire history of the Earth
• All known life during the Cambrian was aquatic, so areas of the United States above sea level would have been sterile wastelands.
• 443 million years ago, Illinois, Indiana, and Michigan were home to vast coral reefs. 
• The Cretaceous ended with mass extinction; roughly half of all animal families became extinct. 
• As the forests thinned during the Cenozoic, grasses began to spread out over the plains of North America, and savannas covered the land in the middle of the continent. 

CHAPTERS
0:00 Start
0:39 Introduction
2:03 Precambrian Era
6:03 Palezoic Era
13:18 Mesozoic Era
19:59 Cenozoic Era
23:06 Outro

RESOURCES
Prehistory of the United States
Precambrian Beginnings - Paleontological Research Institution.
The Paleozoic: Formation of a Continent.
Cenozoic Era: Facts About Climate, Animals & Plants
The Mesozoic: A Story of Mountains and Seas

RPTM Podcast

Episode Two