Every once in a while we stumble upon a peculiar yet smart behavior in the natural world. The clownfish is a perfect example. This fish creates a symbiotic mutualism with sea anemones, a relationship that would benefit both species. Sea anemones are plants that have tentacles that are equipped with stinging cells to keep most fish away. However, the clownfish have developed a protective layer of mucus that covers its body which prevents it from getting stung by the tentacles. With this immunity, clownfish are able eat the parasites that live on the anemone keeping it in good health. In return, the anemone provides it with secure shelter from the rest of the fish that might be a threat to the clownfish. This is especially important during breeding.

The hatching of clownfish was never filmed before, however, the talented team of BBC Earth designed a specialized filming environment to achieve this task. The female clownfish is seen to lay her eggs on the rock beneath the anemone. A female is able to lay up to a 1000 eggs at time. The male then follows by fertilizing the eggs that are now stuck on the rock. The eggs take approximately one week to hatch which often occurs at night. The set was equipped with infrared cameras to be able to film in darkness. The male is seen encouraging the hatchling by pushing them gently with his fins. Once the transparent looking larvae are detached, they spend their first few weeks developing into a beautiful clownfish in the open sea.