New research suggests an ancient hotspot helped shape the Great Lakes, challenging traditional formation theories.

Because of their location in the midlatitudes, the Great Lakes experience the full effect ... In Figure 2 below, the map on the left of each image shows how much colder or warmer than normal ...

The Great Lakes map would provide fuller images of bottom ... Fully mapping the lakes for the first time also could reveal the location of hundreds of shipwrecks — some estimates put the number ...