In this episode, Gabby and AJ talk to Mark Avery, author of A Message from Martha. As a biologist and conservationist, Mark takes us back in time to reconstruct the biology, habitat, and final era of the Passenger Pigeon. The Passenger Pigeon's extinction is one of the most dramatic extinction stories of the 20th century, resulting in the loss of the most numerous bird on Earth. This episode explores everything from nesting biology and historical accounts to habitat destruction and the last P...