Kalmar “genus” tana nufin matsayi na haraji da aka yi amfani da shi a cikin ilmin halitta don rarraba nau’o’in da ke da alaƙa zuwa rukuni bisa halaye masu alaƙa. Kalmar "Dipodomys" ita ce sunan kimiyya ga jinsin kananan rodents da aka sani da berayen kangaroo, waɗanda ake samu a yammacin Arewacin Amirka. Saboda haka, kalmar "Genus Dipodomys" tana nufin rarrabuwar haraji na rukuni na nau'in berayen kangaroo waɗanda ke da halaye iri ɗaya na zahiri da na halitta.