megalodon
noun[C]
uk/ˈmeɡ.əl.ə.dɒn/us/ˈmeɡ.əl.ə.dɑːn/a verylargesharkthatexistedmillions ofyearsago:
（生活在几百万年前的）巨齿鲨For over 20 millionyears, agiganticsharkpopularlyknownas megalodonstalkedthe world's oceans在长达2000多万年的时间里，一种被称为巨齿鲨的巨型鲨鱼游弋在世界各地的海洋中。
Some megalodonteethwere over 7incheslong.一些巨齿鲨的牙齿长度超过7英寸。
- Afull-grownmegalodon could be up to 54feetlong.
- Ourunderstandingof megalodon comesmainlyfromitsteeth.
- Japan andNorthAmericahaveyieldedmegalodonbackbonesas well.
Marine mammals
- beluga
- cetacean
- dolphin
- dugong
- elephant seal
- fur seal
- grey seal
- harp seal
- humpback whale
- killer whale
- minke whale
- monk seal
- narwhal
- orca
- porpoise
- sea cow
- sea lion
- sperm whale
- walrus
- whale