16-05-31 Sloths are famous for being the laziest members of the animal kingdom, so one particularly sprightly member of the species caused quite a stir when it was spotted doing yoga on the side of the road in Costa Rica. 人们都认为树懒是全天下最懒的动物，所...

10-10-19 By examining the development of bones in the vertebral column（脊柱） , limbs, and ribcage（胸腔） , scientists at the University of Cambridge have discovered how sloths（树懒） evolved their unique neck skeleton. From mice to giraffes（长颈鹿） , m...