National Geographic presents brief, but nonetheless fascinating look at a carrier crab, as he stomps around the ocean floor carrying a spiny sea urchin on his back to scare off predators. A few special guests hitch a ride for their own protection too.
Jonathan Bird’s Blue World shares footage of one of nature’s odd relationships – as a hermit crab helps move a pair of anemones from her old shell to a bigger one. The anemones offer the crab protection, and the crab offers food to the anemones. (Thanks Paul!)