Bo-rasaense ba tsoang Canada ba fumane Arctic masalla a nonyana e neng e phela lefatšeng lilemo tse ka bang limilione tse mashome a robong a fetileng. Ka lebaka la se fumanoeng, litsebi tsa paleonton li fumane mohopolo oa hore na boemo ba leholimo ba Arctic bo ne bo le joang mehleng eo ea khale.
Nonyana eo batho ba Canada ba ileng ba e sibolla e ne e le Tingmaitornis arctica. Ho ea ka litsebi tsa paleonto, o ne a e-na le meno 'me a tsoma litlhapi tse khōlō tse jang liphoofolo. Ba boetse ba re nonyana ena ke moholo-holo oa likhofu tsa sejoale-joale ebile e ka ba ea ikakhela e le ho batla lijo tlasa metsi.
Ho khahlisang ke hore ho sibolloa hona ho lebisitse liqetong tse makatsang. Ho ea ka masalla, lilemong tse limilione tse 90 tse fetileng, boemo ba leholimo ba Arctic bo ne bo sa amane le sejoale-joale mme bo ne bo tšoana hantle le tlelaemete ea Florida ea sejoale-joale.
Masalla a lumella bo-ramahlale ho theha maikutlo a itseng mabapi le liphetoho tsa maemo a leholimo tse etsahetseng tikolohong ea Arctic e Upper Cretaceous. Mohlala, bo-rasaense ba pejana, leha ba ne ba tseba hore boemo ba leholimo ba Arctic ba nako eo bo ne bo futhumetse ho feta ba sejoale-joale, ba ne ba nahana hore mariha Arctic e ntse e koahetsoe ke leqhoa.
Lintho tse fumanoeng hajoale li bontša hore ho ne ho futhumetse haholo moo, kaha liphoofolo tseo nonyana e joalo e ka li jang li ka ba teng feela mochesong o futhumetseng. Ka lebaka leo, moea o batang oa nako eo o ne o ka futhumala ho fihlela likhatong tse 28 tsa Celsius.
Ho phaella moo, litsebi tsa paleonto li sa tsoa fumana lehata la phoofolo e sa tsejoeng, e neng e lula California. Ke mang ea nang le lehata ha a e-so hlake, empa maikutlo a hlahisoa hore e ne e le mammoth e neng e phela bonyane lilemo tse likete tse 30 tse fetileng. Ho feta moo, lefu la phoofolo le amahanngoa le pholiso ea lefats'e. Haeba mohopolo o netefalitsoe mme ehlile e tla ba mammoth, joale tsena e tla ba masalla a khale ka ho fetesisa kontinenteng eohle ea Amerika Leboea.
