_Hydrophis cyanocinctus_ is the only sea snake species known to breathe through the top of its head, using a special arrangement of blood vessels in much the same way as fish gills.
Sea snakes spend their lives in the water, giving birth to live young at sea, so why are they only found in some of the world's oceans? The answer lies in a combination of climate and geography.
Snakes have survived millions of years by using their bodies in increasingly creative ways.
From stingers to swans, Australia's oceans are full of (potentially) deadly wildlife.