The question of animal-human similarity is essential to decide whether animals should be treated alike  and whether animals possess rights . What characteristic determines a human being as distinct from animals? What about people with genetic anomalies or other disabilities on the one hand side, and, for example, especially well trained chimpanzees on the other ?
Proponents of animals’ legal status as private property that can be exploited by humans always find new approaches to legitimate the dissimilarity argument like, for example, further experiments designed to identify differences in the perception of pain, which is stimulating additional painful animal research . Evidence from experimental neurological studies of emotional activities shows that intense brain arousal happens in evolutionary shared neural areas that are still common in all mammals. Emotional states matter to animals. It can be easily observed how animals seek rewards and avoid punishments. Such positive and negative learning experiences indicate the existence of psychological and sensitive behavior in all human and non-human mammals .
Especially when fearing punishment, nonhuman and human animals tend to copy the behavior of others . Social learning is vital for the transmission of culture and learning between subjects of high similarity, the so-called assortative social learning, is preferred . The study of conformity has gained popularity in animal research in recent years . Imitation as a social learning mode of animals and humans was already described by Thorndike a couple of centuries ago. Imitative behavior with its high copying accuracy might be essential in cultivating traditions . The limited richness in chimpanzee culture compared to human culture may lie in the higher reliance of children on social rewards while chimpanzees rely more on their own knowledge . There is growing evidence for close analogies of human and chimpanzee social learning and culture .
Some argue that Konrad Lorenz’ study of adaptiveness, i.e., observing stimuli-response behavior in the context of the specific environment (and life experiences , has not been maintained sufficiently in animal research methodology . However, whatever improved scientific methods will reveal, the scientific communities’ and citizens’ judgment regarding which psychological commonalities are of moral relevance and which not, remains an issue that needs careful consideration. We might still not know how inaccurate our understanding of animals’ minds is. Our historically poor understanding  should, in any case, attune us with a rather humble attitude.
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