An unknown earplug through the Countrywide Museum of Purely natural Heritage assortment. The sunshine and darkish levels come from a Construct up of keratin and lipids and can be utilized to estimate whale age. (Megan Chen, NMNH) Baleen whales specialise in Listening to very low-frequency Seems for extended-distance communication. ) https://jamesu638xyy5.wikipublicity.com/user