Tas1r2 pseudogenization and lack of sweet taste responsiveness in cats are probably results of these animals being obligate carnivores that do not seek sugars in their food, and thus do not have a selective advantage of having a functional sweet taste receptor that recognizes sugars. Other species of the order of Carnivora (dogs, Canis lupus familiaris, Canidae family; lesser panda, Ailurus fulgens, Ailurus; domestic ferret, Mustela putorious furo, Mustelidae; Haussa genet, Genetta thierry, Viverridae; meerkat, Suricata suricatta, Herpestidae; and yellow mongoose, Cynictis penicillata, Herpestidae) have a functional Tas1r2 structure[56,57,69] and are attracted to sugars.[69,72,73] Thus, Tas1r2 pseudogenization was an important event in the evolution of the cat’s carnivorous behaviour.
