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Coated droplets hint at formation of early cells

Researchers at the University of Bristol have designed a chemical system that brings together alternative ideas on how primitive cells were formed on the early Earth to produce a new model of protocell organization. The work is described in an article published this week in Nature Chemistry.
The most fundamental requirement for the emergence of cells on the early Earth is the existence of a closed compartment, but how this came about remains a mystery.

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Theory on origin of animals challenged: Animals need only extremely little oxygen

One of science's strongest dogmas is that complex life on Earth could only evolve when oxygen levels in the atmosphere rose to close to modern levels. But now studies of a small sea sponge fished out of a Danish Fjord shows that complex life does not need high levels of oxygen in order to live and grow.
The origin of complex life is one of science's greatest mysteries. How could the first small primitive cells evolve into the diversity of advanced life forms that exists on Earth today? The explanation in all textbooks is: Oxygen. Complex life evolved because the atmospheric levels of oxygen began to rise app. 630 - 635 million years ago.
However new studies of a common sea sponge from Kerteminde Fjord in Denmark shows that this explanation needs to be reconsidered. The sponge studies show that animals can live and grow even with very limited oxygen supplies.

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3 billion-year-old microfossils include plankton

Spindle-shaped inclusions in 3 billion-year-old rocks are microfossils of plankton that probably inhabited the oceans around the globe during that time, according to an international team of researchers.
The researchers not only showed that these inclusions in the rocks were biological in origin, but also that they were likely planktonic autotrophs -- free-floating, tiny ocean organisms that produce energy from their environment.

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Early feast clue to smell of ancient Earth

Tiny 1,900 million-year-old fossils from rocks around Lake Superior, Canada, give the first ever snapshot of organisms eating each other and suggest what the ancient Earth would have smelled like.
The fossils, preserved in Gunflint chert, capture ancient microbes in the act of feasting on a cyanobacterium-like fossil called Gunflintia - with the perforated sheaths of Gunflintia being the discarded leftovers of this early meal.

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Planet's oldest fossils found in Pilbara, experts say

Scientists analysing Australian rocks have discovered traces of bacteria that lived a record-breaking 3.49 billion years ago, a mere billion years after Earth formed. If the find withstands the scrutiny that inevitably faces claims of fossils this old, it could move scientists one step closer to understanding the first chapters of life on Earth. The discovery could also spur the search for ancient life on other planets.
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Ancient Genetic Systems
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Weber State Scientists Discover Possible Building Blocks of Ancient Genetic Systems

Scientists believe that prior to the advent of DNA as the earth's primary genetic material, early forms of life used RNA to encode genetic instructions. What sort of genetic molecules did life rely on before RNA?
The answer may be AEG, a small molecule when linked into chains form a hypothetical backbone for Peptide Nucleic Acids, which have been hypothesised as the first genetic molecules. Synthetic AEG has been studied by the pharmaceutical industry as a possible genesilencer to stop or slow certain genetic diseases. The only problem with the theory is that up to now, AEG has been unknown from nature.
A team of scientists from the USA and Sweden announced that they have discovered AEG within cyanobacteria which are believed to be some of the most primitive organisms on earth. Cyanobacteria sometimes appear as mats or scums on the surface of reservoirs and lakes during hot summer months. Their tolerance for extreme habitats is remarkable, ranging from the hot springs of Yellowstone to the tundra of the Arctic.

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Large bacterial population colonised land 2.75 billion years ago

There is evidence that some microbial life had migrated from the Earth's oceans to land by 2.75 billion years ago, though many scientists believe such land-based life was limited because the ozone layer that shields against ultraviolet radiation did not form until hundreds of millions years later.
But new research from the University of Washington suggests that early microbes might have been widespread on land, producing oxygen and weathering pyrite, an iron sulphide mineral, which released sulphur and molybdenum into the oceans.

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Scientists place 500-million-year-old gene in modern organism

It's a project 500 million years in the making. Only this time, instead of playing on a movie screen in Jurassic Park, it's happening in a lab at the Georgia Institute of Technology.
Using a process called paleo-experimental evolution, Georgia Tech researchers have resurrected a 500-million-year-old gene from bacteria and inserted it into modern-day Escherichia coli (E. coli) bacteria. This bacterium has now been growing for more than 1,000 generations, giving the scientists a front row seat to observe evolution in action.

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Bilaterian
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UAlberta researchers track down earliest known animal

University of Alberta researchers have uncovered physical proof that animals existed 585 million years ago - 30 million years earlier than previous records show.
The discovery was made by U of A geologists Ernesto Pecoits and Natalie Aubet in Uruguay. They found fossilised tracks a centimetre-long, slug-like animal left behind 585 million years ago in silty, shallow-water sediment.
A team of U of A researchers determined that the tracks were made by a primitive animal called a bilaterian, which is distinguished from other non-animal, simple life forms by its symmetry - its top side is distinguishable from its bottom side - and a unique set of "footprints."

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 Mankind's remotest relative is a very rare micro-organism from south-Norway.

Biologists all over the world have been eagerly awaiting the results of the genetic analysis of one of the world's smallest known species, hereafter called the protozoan, from a little lake 30 kilometre south of Oslo in Norway.
When researchers from the University of Oslo, Norway compared its genes with all other known species in the world, they saw that the protozoan did not fit on any of the main branches of the tree of life. The protozoan is not a fungus, alga, parasite, plant or animal.

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