Papers/Resources on the source/process of shame and empathy
Empathy is a topic that has been addressed extensively by Frans de Waal; he has been studying primates intensively and draws parallels between them and us. Especially the differences and commonalities between humans, bonobos and chimps is interesting. Check him out.

Scientific American (a non-peer reviewed scientific journal I'm reading a lot), had a special issue recently (Sci Am, September 2018) on why humans set themselves apart from other animal species. Tomasello has an interesting contribution there on the evolution of empathy and its role in the domination of mankind. An interesting read for sure.