Laughing rats, sorrowful elephants, joyful chimpanzees.  The more carefully we observe, and the more we learn about animals, the closer their emotional lives appear to resemble our own.  Most would agree that we should minimize the physical suffering of animals, but should we give equal consideration to their emotional stress?  Bioethicist Peter Singer weighs in. Meanwhile, captivity that may be ethical: How human-elephant teamwork in Asia may help protect an endangered species. Guests: Frans de Waal - Primatologist and biologist at Emory University; author of “Mama’s Last Hug: Animal Emotions and What They Tell Us About Ourselves.”  Watch the video of Mama and Jan Van Hooff. Peter Singer – Philosopher, professor of bioethics at Princeton University. Jacob Shell - Professor of geography at Temple University, and author of “Giants of the Monsoon Forest: Living and Working with Elephants.” Kevin Schneider - Executive director of the Nonhuman Rights Project