members of the cat family Felidae range from the great,roaring cats such the lion and tiger to the domestic cat. They are separated into different genres (family sub divisions) , not because of their size but because anatomy . These enable members of the genus Panthera to roar, while the small cat in genus Felis cannot do so. there is a third genus for the cheetahs because they have non-retractable claws. Early in the 1900s there were more than 230 different species of cat in the family as a whole,but now there are fewer than 30. Many became extinct because cats have always been hunted and killed by humans for their pelts.