Port Jackson shark

The teeth of the Port Jackson shark are one of its most distinguishable feature. Unlike other sharks, its teeth are different in the front and back. The front teeth are small, sharp and pointed, while the back teeth are flat and blunt. These teeth function to hold and break, then crush and grind the shells of the mollusks and echinoderms upon which this species feeds...

Port Jackson sharks have the ability to eat and breathe at the same time. This ability is unusual for sharks which mostly need to swim with their mouths open to force water over the gills. The Port Jackson shark can pump water into the first enlarged gill slit and out through the other four gill slits. By pumping water across the gills, the shark does not need to move to breathe. It can lie on the bottom for long periods of time...

It also does not pose any danger to humans. In October 2011 a man was 'bitten' by a Port Jackson shark at Elwood Beach near Melbourne. The bite did not pierce the skin and the man was able to swim away while the shark was latched on to his calf.

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