Siltcrete Island in Kati Thanda-Lake Eyre National Park. Australia's largest lake retained water for a record breaking four years; this allowed algae, bacteria and single-celled life forms known as archaebacteria to form. These microorganisms are considered the oldest life forms on Earth. The colour of the water comes from pigments within the cell that produce carotenoids, possibly to protect the cell from ultra violet light which would otherwise destroy it.
Kati Thanda–Lake Eyre, South Australia
Canon EOS 5D MkII, 24–70mm at 50mm, f/2.8 lens, 1/500, f7.1, ISO 320by Peter Elfes, New South Wales