31,000-xyoo-laus skeleton qhia qhov ntxov tshaj plaws paub kev phais yuav rov sau keeb kwm!
Qhov kev tshawb pom no txhais tau hais tias cov neeg thaum ntxov tau paub txog cov txheej txheem phais mob nyuaj, muaj cov ncauj lus kom ntxaws txog kev xav ntawm lub cev dhau ntawm peb qhov kev xav.