For parts of the 20th century, the U.S. and Mexico had agreements in place allowing, and even encouraging, Mexican nationals to enter the U.S. to perform agricultural work and other labor in the American Southwest.
Once the effort to import hippos to the U.S. got the backing of a politician, two men with wild and intertwined histories, Frederick Russel Burnham and Fritz Duquesne, were brought on board to serve as experts and advocates. Read the show notes here.
In the mid-20th century, Chairman Mao Zedong launched an ambitious plan to revolutionize Chinese agriculture and industry, build up the economy and turn China into a communist utopia. Read the show notes here.
The human culture shift to an agricultural lifestyle started the domestication of animals. Cats naturally moved in to help with rodents. Today, there are 600 million cats living with humans, and another estimated 600 million living independent of people.