* Astronomy

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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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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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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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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