Prehistoric Microbes

A microorganism is a microscopic living organism, which may be a single cell or a multicellular organism. The study of microorganisms is called microbiology, a subject that began with the discovery of microorganisms in 1674 by Antonie van Leeuwenhoek, using a microscope of his own design.

Microorganisms are very diverse and include all the bacteria and archaea and almost all the protozoa. They also include some fungi, algae, and certain animals, such as rotifers. Many macro animals and plants have juvenile stages which are also microorganisms. Some microbiologists also classify viruses (and viroids) as microorganisms, but others consider these as nonliving. Read more ...

In the News ...

500 million-year-old fossils show how extinct organisms attacked their prey   PhysOrg - February 17, 2016
The Cambrian Period, which occurred between 541 million and 485 million years ago, is an important point in evolutionary history where most of the major groups of animals first appear in the fossil record. Often called the "Cambrian explosion," fossils from this time provide glimpses into evolutionary history as the world's ecosystems were rapidly diversifying. Most fossils preserve the physical remains of organisms and their structure; however, geologists and paleobiologists at the University of Missouri recently collaborated to study fossils that reveal the behaviors of predators preserved as traces in ancient sediments. Thus, fossils from southeast Missouri are helping scientists unlock clues about the behaviors of these predators and their interactions with their prey. Evidence shows that these ancient organisms were behaviorally sophisticated, tailoring their attacks for effectiveness.

Scientists discover organism that hasn't evolved in more than 2 billion years   PhysOrg - February 3, 2015
An international team of scientists has discovered the greatest absence of evolution ever reported - a type of deep-sea microorganism that appears not to have evolved over more than 2 billion years. But the researchers say that the organisms' lack of evolution actually supports Charles Darwin's theory of evolution. The scientists examined sulfur bacteria, microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia's coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago - and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile.

The origin of life: Labyrinths as crucibles of life   Science Daily - January 28, 2015
Water-filled micropores in hot rock may have acted as the nurseries in which life on Earth began. A team has now shown that temperature gradients in pore systems promote the cyclical replication and emergence of nucleic acids. Water-filled micropores in hot rock may have acted as the nurseries in which life on Earth began. A team at Ludwig-Maximilians-Universitaet (LMU) in Munich has now shown that temperature gradients in pore systems promote the cyclical replication and emergence of nucleic acids. How and in what habitats did the first life-forms arise on the young Earth? One crucial precondition for the origin of life is that comparatively simple biomolecules must have had opportunities to form more complex structures, which were capable of reproducing themselves and could store genetic information in a chemically stable form.

Fossil microbes give sulphur insight on ancient Earth   BBC - August 22, 2011
Tiny structures found within 3.4 bilion-year-old sandstones in Western Australia may represent the oldest direct evidence of life on Earth. Scientists say their analysis of the microfossils clearly shows the organisms were processing sulphur for energy and growth - not oxygen. "At last we have good solid evidence for life over 3.4 billion years ago. It confirms there were bacteria at this time, living without oxygen," said co-researcher Professor Martin Brasier at Oxford University, UK.

Tiny tubes point to ancient life   PhysOrg - October 12, 2010
Tiny tubes thought to have been etched into South African rocks by microbes are at least 3.3 billion years old, scientists can confirm. A new analysis of the material filling the structures shows they were created not long after the volcanic rock itself was spewed on to the seafloor. The tubules could therefore represent the earliest "trace" evidence of activity by life on Earth.

Gabon: Discovery of a complex, multicellular life from over two billion years ago   PhysOrg - June 30, 2010
The discovery in Gabon of more than 250 fossils in an excellent state of conservation has provided proof, for the first time, of the existence of multicellular organisms 2.1 billion years ago. This finding represents a major breakthrough: until now, the first complex life forms (made up of several cells) dated from around 600 million years ago. These new fossils, of various shapes and sizes, imply that the origin of organized life is a lot older than is generally admitted, thus challenging current knowledge on the beginning of life.

Weird Australia Rocks Are Earliest Signs of Life, Study Says   National Geographic - June 8, 2006
Imagine sticking some bacteria in the freezer and taking them out millions of years later to find that they are still alive. That would be similar to what happened recently, when scientists brought eight-million-year-old microbes back to life simply by thawing them.Imagine sticking some bacteria in the freezer and taking them out millions of years later to find that they are still alive. It's also possible that some of the microbes were capable of maintaining their metabolism within tiny droplets of water suspended in the ice. Bidle and colleagues retrieved and revived two samples of bacteria from the glacial ice. The first was a hundred thousand years old, and the second was around eight million years old. The eight-million-year-old bacteria were alive, but barely.

Ancient rocks 'built by microbes'   BBC - June 7, 2006
Odd-shaped rocks in the Pilbara region of Western Australia offer compelling evidence they were built by microbes 3.43 billion years ago, scientists say. The structures, known as stromatolites, could only have taken the forms they have if bacteria had been present, a Sydney-led team tells Nature journal. The rocks' origin is disputed, with some claiming purely chemical processes could have made them.

Early life thrived in lava flows   BBC - April 22, 2004
Geologists have discovered microscopic burrows where some of Earth's earliest life forms bored their way into volcanic glass 3.5 billion years ago. The tubes, from rocks in South Africa's Barberton Greenstone Belt, retain traces of organic carbon left behind by the microorganisms, the authors say. The microbes etched their way into rocks that formed as lava oozed out across a sea floor in Archaean times. The team found ancient microtubules in the Barberton rock which are on average about four micrometres in width and 50 micrometres in length (a micrometre is a millionth of a metre). In the inner walls of these microtubules, the geologists found traces of carbon, which the authors claim is organic.