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RE: Gondwana
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Scientists just discovered chunks of a 'lost continent' in a volcano

The idea of a "lost continent" is a romantic notion that has long since passed from the realm of possibility, but while the chances of actually discovering inhabitable land masses we don't yet know about is essentially zero, researchers believe they now have hard evidence that chunks of the supercontinent Gondwana are actually hidden underneath the island nation of Mauritius.
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Complex animal life
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Study provides strongest evidence oxygen levels were key to early animal evolution

It has long puzzled scientists why, after 3 billion years of nothing more complex than algae, complex animals suddenly started to appear on Earth. Now, a team of researchers has put forward some of the strongest evidence yet to support the hypothesis that high levels of oxygen in the oceans were crucial for the emergence of skeletal animals 550 million years ago.
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Cambrian Extinction
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Evidence that Earth's first mass extinction was caused by evolution, not catastrophe

In the popular mind, mass extinctions are associated with catastrophic events, like giant meteorite impacts and volcanic super-eruptions.
But the world's first known mass extinction, which took place about 540 million years ago, now appears to have had a more subtle cause: evolution itself.

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There's been much debate about why animals took so long to evolve and thrive on Earth.
Now scientists say it was due to incredibly low levels of oxygen on Earth more than a billion years ago.
A team determined the chemical composition of ancient rocks to find there was about 0.1% of the oxygen levels present compared with today.

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Cambrian Explosion
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Title: Did Gamma Ray Burst Induce Cambrian Explosion?
Author: Pisin Chen, Remo Ruffini

One longstanding mystery in bio-evolution since Darwin's time is the origin of the Cambrian explosion that happened around 540 million years ago (Mya), where an extremely rapid increase of species occurred. Here we suggest that a nearby GRB event ~500 parsecs away, which should occur about once per 5 Gy, might have triggered the Cambrian explosion. Due to a relatively lower cross section and the conservation of photon number in Compton scattering, a substantial fraction of the GRB photons can reach the sea level and would induce DNA mutations in organisms protected by a shallow layer of water or soil, thus expediting the bio-diversification. This possibility of inducing genetic mutations is unique among all candidate sources for major incidents in the history of bio-evolution. A possible evidence would be the anomalous abundance of certain nuclear isotopes with long half-lives transmuted by the GRB photons in geological records from the Cambrian period. Our notion also imposes constraints on the evolution of exoplanet organisms and the migration of panspermia.

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A new study led by Adelaide researchers has estimated, for the first time, the rates of evolution during the "Cambrian explosion" when most modern animal groups appeared between 540 and 520 million years ago.
The findings, published online today in the journal Current Biology, resolve "Darwin's dilemma": the sudden appearance of a plethora of modern animal groups in the fossil record during the early Cambrian period.

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RE: Gondwana
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360 million year old fossilised scorpion

A postdoctoral fellow from Wits University has discovered the oldest known land-living animal from Gondwana in a remote part of the Eastern Cape. Dr Robert Gess, from the Evolutionary Studies Institute at Wits, discovered the 360 million year old fossilised scorpion from rocks of the Devonian Witteberg Group near Grahamstown. This unique specimen, which is a new species, has been called Gondwanascorpio emzantsiensis.
His discovery has been published in the peer reviewed journal African Invertebrate.

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Earliest evidence of Gondwana land animals found in Eastern Cape

The earliest evidence of land animals on the ancient southern supercontinent of Gondwana has been found in the Eastern Cape.
It includes a fossilised pincer as well as part of the tail and sting from a species of 360 million-year-old scorpions.
They lived during a geological period known as the Devonian.

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Kooteninchela deppi
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Actor Johnny Depp immortalised in ancient fossil find

A scientist has discovered an ancient extinct creature with scissor hand-like claws in fossil records and named it in honour of movie star.
The 505 million year old fossil called Kooteninchela deppi (pronounced Koo-ten-ee-che-la depp-eye), which is a distant ancestor of lobsters and scorpions, was named after the actor Johnny Depp for his starring role as Edward Scissorhands - a movie about an artificial man named Edward, an unfinished creation, who has scissors for hands.

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Cambrian Explosion
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The Cambrian Explosion

Thu, 17 Feb 05

Duration: 43 mins

Melvyn Bragg examines the Cambrian period, when there was an explosion of life on Earth. With Simon Conway Morris, Richard Corfield and Jane Francis.

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