How similar are humans and other animal species? Do animals think about the same things as us humans? Are they conscious beings? In Clive Wynne's book Do Animals Think? he debunks much of our popular knowledge about the animal kingdom. He claims that the problem is that human qualities are always transferred to animals rather than recognizing that each species is unique with specific adaptations for their way of life. He proposes a metaphor for comparing human and non-human animal abilities: a similarity sandwich. This sandwich has three layers: a bottom layer of dissimilarity where all species are distinguishable and have their own perceptual and sensory abilities, a middle, sludgy layer of similarity, that is a broad, ambiguous zone of features and abilities that animals and humans share, and a top layer of dissimilarity containing characteristics that are unique to humans.