They are among the largest mammals on earth, but also among the most invisible: humpback whales are an enigma to scientists who can't observe much of their underwater activities. To unlock the secrets of humpback behavior, researchers have turned to sound to hear what they cannot see. Join us on an underwater visit to the whales on their feeding grounds near Sitka, Alaska. The remarkable sounds discovered there are causing scientists to forge new theories about whales and why they sing.
Regular price: $3.95
Join Producer Lisa Busch as she explores the Alaska caves they pre-date the Ice Age, it's only been relatively recently since geologists identified a vast cave system tunneling through south east Alaska. Scientists have determined that the caves serve as a drainage system for the timber lands around them, providing an outlet for an enormous amount of rain, up to 150 inches a year. Archeologists who study early migration think humans used the caves to move up and down the coastline in small boats.
Regular price: $1.95