Why Some Animals Evolved to Sacrifice Themselves動(dòng)物為何舍身繁衍

A male musk ox can weigh up to 800 pounds and charge at speeds over 30 miles per hour. During the breeding season， these shaggy1， Arctic Circle behemoths crash into each other face-first and then stab their opponents with their huge， sharp horns.

一頭雄性麝牛體重可達(dá)800磅，奔跑速度超過(guò)30英里/小時(shí)。（剩余7233字）