Humpback whales have been using seaweed as a tool — and now, scientists might have figured out how and why.
Whales frequently engage in "kelping," or seaweed-based play in which the sea mammals roll with kelp, move it around with their fins, and put it on their heads like a hat or a wig.
Since kelping sessions sometimes last between 30 and 40 minutes, scientists began to wonder if there's something beneficial about the practice beyond its apparent fun factor.
"That's quite a lot of time to just spend with a little piece of algae," Olaf Meynecke, the study's author and a research fellow at Griffith University, told National Geographic. "It looked like there had to be more to it."
Meynecke suggested that kelping might positively affect whales' skin and may also be helpful for mobility training that enhances the physical coordination necessary for feeding. He thought that since seaweed is naturally antimicrobial, whales may unwittingly use the plants for a natural skincare routine that can reduce bacteria and prevent infections.
Researchers also say that whales sometimes put kelp in their mouths, which they liken to flossing. "Grabbing something with their mouth is not natural for them," Meynecke told NatGeo. "They're not like cats. They don't hunt with their teeth—they don't have teeth."
Seaweed isn't just valuable to whales — humans have figured out ingenious uses for the material, too. A developer has been building houses made of seaweed bricks, scientists are working on using seaweed as an anti-pollutant in soil, and packagers are finding ways to use seaweed as a plastic alternative.
Scientists first observed kelping in 2007 in several species of baleen whales, including gray whales. The practice has been noticed worldwide, and research has been enhanced by social media documentation, according to National Geographic.
Meynecke said his research "would never have made it out there if it wasn't for the people getting excited that they just saw a whale putting kelp on their head, and posting about it."
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