Comments by "belstar" (@belstar1128) on "The Evolution of Whale Echolocation" video.

i always think its interesting how land animals adapted to sea life. life in the sea seems impossible for most land based animals. i guess they lived on the shores or small swampy islands for such a long time they would spend most of their time hunting in the sea and they would spend more and more time in the water until they were more adapted to life in the sea than on land .and could no longer even live on land. yet unlike fish they still can't breathe underwater .how long would it take for them to evolve gills like fish and be able to breathe under water? i guess it would take over 100 million years at least.
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