In the ocean off Japan an industrious pufferfish has been crafting elaborate sand sculptures. And they're spectacular!
|The sculptures created by the pufferfish (photos Yoji Ookata)|
The sculptures appear to be sexually selected. Only the males make them and females prefer to mate with males who make sculptures with more ridges. During mating the eggs are laid into the center of the sculpture where they may receive some protection from the currents preventing them from being dispersed far and wide.
|A male pufferfish creating a sculpture (photo Yoji Ookata)|
These pufferfish (I can't work out the species) are not the only fish to make sand sculptures. Many species of African cichlids make structures, known as bowers (after the bowerbird), that function in sexual selection too. But, for many species the bowers, although they appear nest-like, do not hold the eggs. The female broods them in her mouth until they hatch and often longer.
|A male cichlid patrols his volcano shaped sandcastle in Lake Malawi (photo Justin Marshall)|