Why in News:

• Rocks on the surface of Mars that look like layers of pasta may be the most obvious sign of life on the Red Planet

Background: / Sulfurihydrogenibium yellowstonense:

• The bacterium that controls the formation of such rocks on the earth is ancient and thrives in harsh environments that are similar to conditions on Mars
• The bacterium belongs to a lineage that evolved prior to the oxygenation of Earth roughly 2.35 billion years ago.
• It can survive in extremely hot, fast-flowing water bubbling up from underground hot springs.
• It can withstand exposure to ultraviolet light and survives only in environments with
  extremely low oxygen levels, using sulphur and carbon dioxide as energy sources.