Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Tsoffin burbushin da aka sani na yawancin umarnin dabbobi masu shayarwa na zamani sun bayyana a cikin ɗan gajeren lokaci a farkon Eocene. A farkon Eocene, sabbin kungiyoyin dabbobi masu shayarwa da yawa sun isa Arewacin Amurka. Wadannan dabbobi masu shayarwa na zamani, kamar su artiodactyls, perissodactyls da primates, suna da fasali kamar dogayen kafafu masu kauri, ƙafafu da hannaye masu iya kamawa, da kuma hakora daban daban da suka dace da tauna. Tsarin Dwarf ya yi sarauta. Dukkanin membobin sabbin umarnin dabbobi masu shayarwa sun kasance kanana, a karkashin kilo 10; bisa ga kwatancen girman hakori, dabbobi masu shayarwa na Eocene sun kasance kashi 60% ne kawai na girman dabbobi masu shayarwa na Palaeocene wadanda suka gabace su. Su ma sun fi ƙananan dabbobi masu shayarwa da suka bi su. An ɗauka cewa yanayin zafi na Eocene ya fi son ƙananan dabbobi waɗanda suka fi iya sarrafa zafin.  Tambaya: Wane irin kafafu ne dabbobi masu shayarwa na zamani suke da shi?
dogon kafafu masu kauri