VOA慢速英语:新墨西哥沙漠出现捕猎证据

tip-toe – n. the action of touching the ground only with one's toes

associated – adj. closely connect with another person or thing

extinction – n. the act of making something die out

unique – adj. special; unusual

unequivocal – adj. very strong or clear

vertebrate – n. any of the bony pieces making up the backbone