The Rev. Victoria Weinstein is pastor of First Parish Church of Norwell, Mass., a Unitarian Universalist congregation. In May 2006, she delivered a sermon on the spiritual value of animals.

Christine Gutleben is director of the animals and religion program for the Humane Society of the United States. She has an undergraduate degree in religious studies and a master’s degree from a theology school, where she studied theology and ethical food choices.

Saurabh Dalal is president of the Vegetarian Union of North America. He spoke at a panel on religious outreach at the 2009 Animal Rights Conference in Washington, D.C. He lives in Lanham, Md.

Michael Croland is the writer behind heeb’n’vegan, a blog about Jewish veganism.

Dr. Michael Greger is a physician and director of public health and animal agriculture in the farm animal welfare division of the Humane Society of the United States. He is an expert on the public-health implications of using antibiotics and growth hormones in livestock and other food-safety issues.

Rynn Berry is the author of Food for the Gods: Vegetarianism & the World’s Religions and an adviser to the North American Vegetarian Society. He is based in New York City.

Calvin DeWitt is a professor at the Nelson Institute for Environmental Studies at the University of Wisconsin-Madison. He is concerned with the ethics of farming and uses of the natural environment, including animals. He is co-founder of the International Evangelical Environmental Network.

Kerry Walters is a philosophy professor at Gettysburg College in Gettysburg, Pa. With Lisa Portmess, she co-authored two books, one about the history of religious vegetarianism and the other on the history of ethical vegetarianism.

Lisa Portmess is a philosophy professor at Gettysburg College in Gettysburg, Pa. With Kerry Walters, she co-authored two books, one about the history of religious vegetarianism and the other on the history of ethical vegetarianism.