title: Waxbaa dhulka ku dhacay oo ka caawiyay inay tirtiraan mammoths iyo xayawaan kale 13,000 sano ka hor, daraasad ayaa sheegeysa
abstract: qiyaastii 13,000 oo sano kahor xayawaanada waawayn sida mastodons, mammoths, bisadaha ilkaha leh iyo sloths ayaa dhulka ka baaba'ay. Seynisyahanada waxay heleen cadeymo ku saabsan nuucyada burburka si ay u taageeraan aragtida muranka dhaliyay ee ah in asteroid ama komet uu ku dhacay dhulka kuna caawiyay dabar goynta xayawaanka xilligii barafka iyo qaboojinta adduunka.