In this episode, Jamie follows a trail of clues starting from Toronto’s Scarborough Bluffs —and then going billions of years deeper into Earth’s past.

What begins as a question about where the Great Lakes came from becomes a story of ancient tropical seas, moving continents, enormous ice sheets, a failed continental rift, changing shorelines, and even the cosmic dance of our solar system.

The deeper lesson is personal: the familiar landscape around us can look ordinary until we learn how to read it.

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Where We're Exploring

Further Reading

A few useful places to dig deeper into the science behind the episode:

• USGS — The Geologic Story of the Great Lakes — How bedrock, ancient landscapes and glaciers came together to create the Great Lakes.
  Read the USGS guide

• National Park Service — How Glaciers Change the Landscape — A clear introduction to glacial erosion, plucking, abrasion and deposition.
  Read more

• NASA — Milankovitch Cycles — How eccentricity, obliquity and precession influence Earth's climate.
  Explore the cycles

• NASA — The Mechanics of Glacier Motion — What actually makes enormous sheets of ice move.
  Learn how glaciers move

• Canadian Museum of Nature — The Pakenham Whale — The remarkable story of the Ice Age beluga found beneath an Ontario farm.
  Read the story

• University of Toronto — Prehistoric Toronto — Toronto's landscape during and after the Ice Age.
  Explore Prehistoric Toronto

• University of Toronto — Georgian Bay Geopark — Ancient rocks, mountain building, supercontinents and the deep geological history of the region.
  Explore the Georgian Bay Geopark

• USGS — The Midcontinent Rift — The billion-year-old continental rift that helped shape the Lake Superior region.
  Read about the Midcontinent Rift

• Parks Canada — Fathom Five Geology — The ancient tropical seas and unusual rock formations around Tobermory and Flowerpot Island.
  Explore Fathom Five's geology

• City of Toronto — Scarborough Bluffs — The history, geology and ongoing erosion of one of Toronto's most dramatic landforms.
  Read about the Bluffs

• Ontario — Long Point Provincial Park — The dunes and shifting sand-spit landscape of Lake Erie.
  Explore Long Point

• USGS — Great Lakes Climate & Water Resources — A broader look at the Great Lakes today, including water levels, climate and changing conditions.
  Read the USGS report

Want to Keep Learning?

Download the Full Episode Companion Guide

It's got cool things like maps showing the

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