Umboni watsopano ukusonyeza kuti anthu ayenera kuti anakakhala ku South America zaka 25,000 zapitazo.
Osteoderms - zida zokhala ngati mafupa ankhondo zopezeka mu nyama ngati armadillos - zopezeka kumalo osungiramo miyala ya Santa Elina ku Brazil, pafupi ndi zida zamwala, zinali ndi zibowo zazing'ono zomwe zikanapangidwa ndi anthu okha.
Pepala lomwe linatulutsidwa pa July 12 m'magazini Proceedings ya Royal Society B inanena kuti kupezeka kumeneku kungakhale chimodzi mwa zizindikiro zoyambirira za kukhalapo kwa anthu ku America.
Kuyambira mu 1985, akatswiri ofukula zinthu zakale akhala akufufuza malo obisalira miyala a Santa Elina m’chigawo cha Mato Grosso, ku Brazil. Kafukufuku wam'mbuyo adavumbulutsa ziwerengero ndi zizindikiro zoposa chikwi pa makoma, mazana a zida zamwala, ndi masauzande a ma sloth osteoderms, atatu mwa omwe adabowoledwa ndi anthu.
Kafukufuku waposachedwapa anaunika bwinobwino za mafupa otchedwa sloth osteoderms, ndipo n’kutheka kuti mabowo amene ali m’mafupawo ndi amene anayambitsa anthu. Kupeza kumeneku kumakankhira mmbuyo tsiku lomwe anthu akukhala ku Brazil ku 25,000 mpaka 27,000 zaka, malinga ndi umboni wotsutsana wa ntchito ya anthu oyambirira ku South America, monga malo osungira miyala a Toca da Tira Peia kum'mawa kwa Brazil zaka 22,000 zapitazo.
Gululo lidagwiritsa ntchito njira zowonera zazing'ono komanso zazikulu kuti zitsimikizire kuti ma osteoderms ndi ting'onoting'ono tawo tapukutidwa. Kuphatikiza apo, gululo lidawona zobowoka ndi zokwala zosonyeza kuti zidapangidwa ndi zida zamwala. Kuphatikiza apo, adatha kuletsa makoswe ngati omwe amapanga mabowowo chifukwa chokhala ndi zizindikiro zolumidwa ndi nyama pama osteoderms onse atatu.
Zomwe zapezazi zikuwonetsa kuti ma osteoderms atatu adasinthidwa ndi anthu kukhala zinthu zakale, zomwe mwina zidagwiritsidwa ntchito ngati zodzikongoletsera zaumwini, malinga ndi olemba mu kafukufukuyu.
M’kalata yake yopita ku Live Science, Mirian Pacheco, mphunzitsi wa sayansi ya zinthu zakale pa yunivesite ya Sao Carlos, ku Brazil, ananena kuti “n’zosatheka kulongosola tanthauzo lenileni la zinthu zimenezi kwa anthu okhala ku Santa Elina.” Komabe, mawonekedwe ake ndi kuchuluka kwa ma osteoderms "mwina akhudza kupanga mtundu wina wa zinthu zakale monga pendenti," adatero.
Zida zamiyala zopezeka pambali pa mafupa osinthidwe a kaloŵa opangidwa ndi anthu m'mizere ya nthaka yomwe akuti ndi ya zaka 25,000 mpaka 27,000, zikusonyeza kuti anthu anafika ku South America kale kuposa mmene ankaganizira poyamba.
Thaís Pansani, katswiri wodziwa zinthu zakale wa ku Federal University of Sao Carlos ku Brazil, adanenanso mu imelo ina ku Live Science kuti umboni umagwirizana ndi lingaliro lakuti anthu anali ku Central Brazil pafupifupi zaka 27,000 zapitazo, zomwe zakhala mgwirizano pakati pa anzake pa ntchito. zaka 30 zapitazi.
Matthew Bennett, katswiri wa geologist pa yunivesite ya Bournemouth, anachita kafukufuku wokhudzana ndi kugwirizana kwa ulesi ku North America ndipo sanachite nawo ntchitoyi. Zomwe anapeza zikusonyeza kuti anthu akale ankagwiritsa ntchito mabwinja a kanyamaka pazifukwa zosiyanasiyana.
Mu imelo ku Live Science, Bennett adanena kuti ntchitoyi ili ndi kuthekera kothandizira lingaliro la anthu okhala ku America panthawi ya Last Glacial Maximum, yomwe inali nyengo yozizira kwambiri m'nyengo yachisanu yomaliza.
Ngakhale zili choncho, malo ambiri ku South America sanafufuzidwe mozama, choncho nkhani yonena za kuyambika kwa anthu ku America ikupitirizabe. Tili ndi lingaliro kuti zambiri zikuyembekezeka kupezeka m'matanthwe ndi mapanga aku Brazil omwe sanafufuzidwebe.
