Bajau divers of the Central Sulawesi peninsula in Indonesia are able to hold their breath and dive to amazing depths of over 200 feet using only rock weights and hand-made wooden goggles.

A common seaweed called rainbow wrack grows along Europe’s coasts, including tidal rock pools in the UK. Deep inside its cells, this marine plant uses oily chemicals to make opal look-alikes—“living opals.” This discovery intrigues nanotechnologists.