Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Hanyar wucewa: An raba squirrels da suke da rai zuwa rukuni biyar, da suke da jinsuna 58 da kuma nau'i-nau'i 285. Tsohon burbushin squirrel, Hesperopetes, ya samo asali ne daga Chadronian (karshen Eocene, kimanin shekaru miliyan 40-35 da suka gabata) kuma yayi kama da squirrels masu tashi na zamani. Abubuwan burbushin halittu iri-iri, daga Eocene na ƙarshe zuwa Miocene, ba a sanya su da tabbaci ga kowane zuriya mai rai ba. Aƙalla wasu daga cikin waɗannan tabbas sun kasance bambance-bambancen tsofaffin "protosquirrels" na asali (a ma'anar cewa ba su da cikakkiyar kewayon autapomorphies na squirrels masu rai). Rarraba da bambancin irin waɗannan tsoffin siffofin da kakanninmu sun nuna cewa squirrels a matsayin rukuni na iya samo asali ne a Arewacin Amurka. Ban da waɗannan nau'ikan burbushin halittu da ba a san su ba, tsarin ilimin squirrels na yau da kullun yana da sauƙi. Manyan kabilu guda uku sune Ratufinae (gizo giant squirrels), Sciurillinae da duk sauran ƙananan iyalai. Ratufinae ya ƙunshi nau'ikan halittu kaɗan ne kawai a yankin Asiya na wurare masu zafi. Neotropical pygmy squirrel na wurare masu zafi na Kudancin Amurka shine kawai memba mai rai na Sciurillinae. Tsarin na uku, wanda ya fi girma, yana da kusan rarraba duniya. Wannan yana ƙara tallafawa hasashen cewa kakannin kowa na dukkan squirrels, masu rai da burbushin halittu, sun rayu a Arewacin Amurka, kamar yadda waɗannan tsoffin layin uku suka fito daga can; idan squirrels sun samo asali ne a Eurasia, alal misali, mutum zai yi tsammanin tsoffin layin a Afirka, amma squirrels na Afirka suna da asali ne na kwanan nan. Babban rukunin squirrels kuma za a iya raba shi zuwa rukuni uku, wanda ya haifar da sauran ƙananan iyalai. Sciurinae yana dauke da masu tashi sama (Pteromyini) da Sciurini, wanda a tsakanin wasu ya ƙunshi masu bishiyar bishiyar Amurka; tsohon sau da yawa ana daukar su a matsayin wani yanki na daban, amma yanzu ana ganinsu a matsayin kabila na Sciurinae. A gefe guda kuma, squirrels na Pine (Tamiasciurus), galibi ana haɗa su tare da asalin squirrel na itace, amma da alama sun bambanta kamar squirrels masu tashi;...  Tambaya: Iyalai nawa ne aka raba masu squirrels?
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