Final answer:
Barbara J. King's post-retirement work revolves around animal grief, the importance of science for the public good, and social change. She actively engages with the public through writing, speaking, and contributing to media on these themes.
Step-by-step explanation:
The general theme of Barbara J. King's work after leaving her position as a professor can be described as focusing on the subjects of animal behavior, emotion, and the impact of science on society. Since her retirement in 2015, King has continued her involvement in academia and public outreach through various media.
Her research on animal grief, which was encapsulated in her book How Animals Grieve, has been particularly influential and was the highlight of her 2019 TED Talk titled “Grief and Love in the Animal Kingdom”. Additionally, she has been actively reviewing books and publishing articles on topics related to anthropology, further advocating for the importance of science for public good and social change.