Considerable attention is paid to issue of things at the present time. The new Czech Civil Code (NOZ) introduces big changes, one of these changes is definition of things „in a wide-ranging way“, including introducing the term of things we cannot touch (res incorporales of Roman Law). In this context, the particular importance has the concept of animal. The article examines the concept of animal in the Czech and Roman Law, especially relationship between man and dog. The legal regime of a dog in the Roman Law and in the present Czech Law is significantly different. The Roman Law considered the dog as a thing and dogs in Roma had the same status as other things (including slaves). The article deals with the legal status of dogs as things, masteręs responsibility for a damage caused by their dog (actio de pauperiae). In the Czech Law in contrary, an animal does not have the status of thing, but „entity“, that is different. However, dogs in ancient Rome had the special status as well as in the Czech Republic nowadays. In Rome, dogs were considered as an example of fidelity (canis fidelis), dogs were not only hunting companions, but also pets (pets). Dogs were provided with special care by doctors-specialists, we have preserved statues of dogs and their image on headstones, together with their masters. We can find the same status of dogs also in life of present-day Czechs who invest large sums in the health care for dogs, in their diet and even in their look. Then we can see that despite the different legislation in the Czech Republic and in ancient Rome, the position of man and dog is very similar, despite all the social and cultural differences. The article deals with the matter of roots of such position. It seeks the answer by means of evolution psychology in human race prehistory. The close relationship to the dogs is given by the fact that dogs were the first domesticated animals. The article describes the process of domestication when dogs became guards of prehistoric peopleęs home, as well as their companions on hunting. This is how the strong bond between man and dog was created and it continues until these days.