The first organisms

Bacteria have been the very first organisms to live on Earth. They made their appearance 3 billion years ago in the waters of the first oceans. At first, there were only anaerobic heterotrophic bacteria (the primordial atmosphere was virtually oxygen-free). The first autotrophic bacteria, very similar to the current cyanobacteria, appeared approximately 2 billion years ago. Photosynthesis occurred in these organisms and this is how the atmosphere was enriched with precious oxygen. Cyanobacteria or blue algae made the primitive atmosphere breathable and allowed life to colonise the lands above sea level.
Man has just recently become aware of the existence of bacteria because they were too small to be observed or studied before the microscope was invented.

Special reports

  • 3 November 2014

    Conan the bacterium

    Have you ever leafed through the pages of a book of Guinness World Records? You can find records of all…

  • 5 February 2010

    Extreme bacteria

    Researchers from the Cnr with Bruno D’Argento and...

  • 4 March 2010

    Biotechnological cleaners

    In today’s society, more than 80% of human activities are...

From the Multimedia section

Facts

  • Bio-luminescence

    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

    Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

    Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...

  • Bacteria as Sherlock Holmes

    A drop of blood, a fragment of skin or a hair found on the scene of a crime can supply…

    Down-pouring bacteria

    It sounds incredible, but recent researches have found that bacteria can cause some atmospheric phenomena...

    High-fashion bacteria

    Some bacteria, the Clostridia, were used to make textile fibres...

  • Let’s eat!

    The economic importance of fungi is increased by the “edible” mushrooms...

    Predator mushroom

    <em>Pleutrotus ostreatus</em> mushroom does not have teeth or claws but it is...

    A super-milk

    Some protozoa have attracted the interest of the biotechnological research world...

  • 13 May 2011

    Bio-luminescence

    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

    Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

  • Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...

    Bacteria as Sherlock Holmes

    A drop of blood, a fragment of skin or a hair found on the scene of a crime can supply…

  • Down-pouring bacteria

    It sounds incredible, but recent researches have found that bacteria can cause some atmospheric phenomena...

    High-fashion bacteria

    Some bacteria, the Clostridia, were used to make textile fibres...

  • Bio-luminescence

    Many sea animals, including a lot of fish and molluscs that live in the dark in the ocean depths...

  • Bacteria as detergents

    Enzymes are proteins produced by the cells of all living organisms...

  • Bacteria as miners

    The ability of chemoautotrophic bacteria to take energy from...