Figure 12 in External brain anatomy in relation to the phylogeny of Caninae (Carnivora: Canidae)

Figure 12. The living raccoon dog (Nyctereutes procyonoides) is considerably smaller than the fossil †Nyctereutes sinensis, which is considered its ancestor (see discussion in the text). As presented in this study, the fossil Nyctereutes species have a larger proreal gyrus than the living species. A similar development is seen in the frontal sinus, which is also larger in the fossil species than in the living form (Tedford et al., 1995). These two points are the subject of the cartoon: in China 3 million years ago, a Vulpes (which lacks a frontal sinus and has a proreal gyrus very small) is very enthusiastic with the new ideas of a Canis (in which both features are very well developed), however, the Nyctereutes does not seem to be interested at all.