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What animal proposes with rocks?
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September 28, 2026 Fact of the Day Birds Penguins ‘propose’ with rocks. By Bennett Kleinman Much like humans, penguins also propose with rocks — but not the ones sold at jewelry stores that cost three months’ salary. Instead, male penguins scour the barren Antarctic beaches for the perfect pebble to present to their preferred partner. To be clear, these stony gestures have little to do with romance; rather, these gift exchanges serve a more practical purpose related to nest-building. Given the dearth of twigs, brush, and other foliage in their cold-weather environments, species such as the gentoo, chinstrap, and Adélie penguins use the small stones to elevate their eggs off their ground. The more rocks, the better and sturdier nest to protect eggs from potential flooding caused by melting snow. Meet nature’s biggest hoarders Today's Question What animal collects piles of its own discarded heads? Stovepipe Hopper Totem Inchworm Skull-Stacking Grub Mad Hatterpillar Keep Exploring Birds How Do Penguins Tell Each Other Apart? Across Species Do Lobsters Mate for Life? Birds How Do Penguins Stay Warm? Was this email forwarded to you? Sign Up Advertise Contact Us Privacy Policy Terms of Use 325 North LaSalle Street, Suite 200, Chicago, IL 60654 If you'd like to unsubscribe from all Animal Facts emails, click here.