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Post Info TOPIC: Ancient life
Blobrana


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Deep life
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Primitive bacteria exist in huge numbers deep in the Earth, living on hydrogen gas produced in rocks.
Recent studies suggest that the mass of bacteria existing below ground may be larger than the mass of all living things at the Earth’s surface, according to recent studies cited by the paper's lead author, Friedemann Freund, who works at NASA Ames Research Center in California's Silicon Valley. Similar hydrogen-consuming microbes may some day be discovered on Mars, raising new prospects for the possible existence of life beyond Earth

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Blobrana


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Scientists found a gold mine of bacteria almost two miles beneath the Earth’s surface.
The subterranean microorganisms, a division of Firmicutes bacteria, use radioactive uranium to convert water molecules into useable energy. Uranium is an element contained within the Earth’s crust and is an abundant source of energy.
The presence of such terrestrial organism raises the potential that bacteria could live beneath the surface of other planets such as Mars.

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Blobrana


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Methane Devourer Discovered in the Artic
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Novel methane consuming microorganisms discovered at the Haakon Mosby Mud Volcano in the Arctic deep sea
Not lava, but muds and methane are emitted from the Arctic deep-water mud volcano Haakon Mosby. When it reaches the atmosphere, methane is an aggressive greenhouse gas, 25-times more potent than carbon dioxide. Fortunately, some specialised microorganisms feed on methane and thereby reduce emissions of this greenhouse gas. For the first time, a German-French research team showed which methane consuming microorganisms thrive in the ice-cold Arctic deep-sea. In an article in the journal Nature, the scientists also describe which environmental parameters control their activity - with a surprising result: High flow velocities of mud volcano water in the seafloor reduce the efficiency of the natural gas filter by 60%.

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Blobrana


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Fossil shell discovered on farm
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Horn coral is a link to what area looked like in prehistoric times
In her mind's eye, Beulah Songer can see a vast prehistoric lake stretching from one side of the Sequatchie Valley (Tennessee) to the other.
In her vision, a small sea animal lies in the sandy waste that eventually will preserve it in layers of stone. Quiet waves lap against a shoreline that humans in the distant future would call the west side of Waldens Ridge.

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Blobrana


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Ancient fossil embryos
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The exact moment when a 550 million year old cell began to divide has been captured in an exquisite 3-D image.
The picture is one of a series taken by researchers examining ancient fossil embryos from Guizhou Province, China.

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Blobrana


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RE: Ancient life
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Oldest Embryo Fossils Provide Picture of Early Animal Life
Roughly 600 million years ago, thousands of embryos of primitive animals drifted into seawater laced with sulfides and died. But in addition to potentially killing them, the sulfides protected the microscopic nascent creatures and permitted the process of fossilisation to occur. Research in the Doushantuo Formation in China uncovered these fossilized embryos--among the rarest of finds both for their fragile nature and depth in past time--and new imaging techniques have provided a window into the internal workings of the most ancient animals yet discovered.

Whitey Hagadorn of Amherst College led an interdisciplinary and international team of scientists that isolated 162 of the most well-preserved specimens. Each showed evidence of an intact fertilisation envelope--the surrounding membrane that kept the dividing cells together--as a change in the encompassing rock.

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Blobrana


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Cambrian explosion
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A continental crash that raised one of the biggest mountain chains in the Earth's history may be responsible for the explosive diversification of animals more than 500 million years ago.

Sediments washed from the mountains – dubbed the Transgondwanan Supermountain – added vital nutrients to the ocean, opening new evolutionary opportunities, says Rick Squire, now at Monash University in Clayton, Victoria, Australia.
The rapid proliferation of animals that occurred at that time is one of evolution's biggest enigmas. Life had remained simple and largely single-celled for nearly three billion years, until the multi-celled Ediacara fauna evolved, 575 million years ago.
Most major groups of animals evolved during a second radiation, called the Cambrian explosion, from 530 to 510 million years ago. The mystery of what suddenly kick-started animal evolution has been a topic of hot debate among experts.

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Blobrana


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Deep life
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Ocean scientists discover how bacteria produce propane in the deep seafloor

During an expedition off the South American coast, an international team of ocean scientists discovered that the gases ethane and propane are widespread, and are being produced by microorganisms in deeply buried sediments. Prof. Kai-Uwe Hinrichs (Research Centre Ocean Margins, University of Bremen), co-author Prof. John Hayes (Woods Hole Oceanographic Institution), and colleagues report new findings on the production of energy-laden gases in a paper in this week's online edition of the renowned Proceedings of the National Academy of Sciences of the U.S.A. (PNAS). The findings suggest that microbes in the deeply buried, vast ecosystem below the seafloor carry out hitherto unrecognised processes, which are highly relevant to both our understanding of global element cycles and the metabolic abilities of Earth's microbial biosphere.

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Blobrana


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RE: Ancient life
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The earth is full of locales seemingly inhospitable to life. In areas like that deep beneath the ocean's mud floor, oxygen cannot penetrate. In such anoxic environments, the simple cellular precursors of all life--bacteria and archea--thrive, but the single-celled ancestors of more complex life-forms, known as eukaryotes, were thought to suffocate. Now new research has shown that at least one eukaryotic species--a shelled, amoebalike creature called a foraminifer--can prosper without oxygen by respiring nitrogen instead.

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Blobrana


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The detailed images of embryos more than 500 million years old have been revealed by an international team of scientists, led by the University of Bristol.

Writing in the journal Nature, Dr Phil Donoghue and colleagues reveal the various developmental stages of fossilised embryos, from the first splitting of cells to pre-hatching, using synchrotron-radiation X-ray tomographic microscopy (SRXTM).
In one instance this has exposed the internal anatomy of the mouth and anus of a close relative of the living penis worm. Another case has revealed a unique pattern for making embryonic worm segments, not seen in any animals living today.



"Because of their tiny size and precarious preservation, embryos are the rarest of all fossils. They are just gelatinous balls of cells that rot away within hours. But these fossils are the most precious of all because they contain information about the evolutionary changes that have occurred in embryos over the past 500 million years" - Phil Donoghue, University of Bristol

This work has enabled the reinterpretation of previous data on fossilised arthropod embryos, showing that they are similar to those found in modern arthropods (insects and crustaceans). This suggests that arthropod evolutionary history must be pushed further back in time than previously thought.
Using SRXTM at the Swiss Light Source of the Paul Scherrer Institute in Switzerland, the team obtained complete three-dimensional images of the fossilised embryos at sub-micrometre resolution. The scans from these experiments are then manipulated in a computer to reconstruct the internal anatomy of the fossil embryos, unlocking the finest details of their preserved anatomy and revealing their hidden secrets.
The present study demonstrates the feasibility of the method for a variety of questions concerning developmental processes in early fossil animals.

Source University of Bristol

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