Our commentators come from many fields and disciplines and express highly divergent views, illustrating broad interest in the question. From the breadth of comments, we have identified two recurring themes, which we focus on here. The first is a preponderance of cautionary remarks about evaluating the differences between humans and nonhuman animals. The second concerns whether considering animals as worthy of moral consideration is one of many useful tools for conservationists trying to prevent extinction, habitat destruction, and climate change
