 Phylogenetic analysis shows evidence of fourteen discrete evolutionary transitions to cooperative breeding within the class Mammalia.These lineages are nine genera of rodents ("Cryptomys", "Heterocephalus", "Microtus", "Meriones", "Rhabdomys", "Castor", "Atherurus" and two in "Peromyscus)," four genera in Carnivora "(Alopex, Canis, Lycaon, and in mongooses), and one genera of primates (Callitrichidae).