Newly discovered fossils … world’s first mass extinction engineered by by early animals

[OKIsItJustMe]

http://news.vanderbilt.edu/2016/07/newly-discovered-fossils-strengthen-proposition-that-worlds-first-mass-extinction-engineered-by-early-animals/

[font face=Serif][font size=5]Newly discovered fossils strengthen proposition that world’s first mass extinction engineered by early animals[/font]

by David Salisbury | Jul. 29, 2016, 9:12 AM


[font size=1]Fossils from Zaris site in Namibia: left, the discs are fossil remains of the holdfast structures that were holdfast structures for an Ediacaran species called aspidella; middle, bumps on the rock surface are the remains of burrows, called conichnus burrows, that were originally inhabited by anemone-like animals that may have fed on Ediacaran larvae; right, odd annulated and ribbon-like fossils that represent mysterious early animals (likely ecosystem engineers) called shaanxilithes. (Simon Darroch / Vanderbilt)[/font]

[font size=3]Newly discovered fossil evidence from Namibia strengthens the proposition that the world’s first mass extinction was caused by “ecosystem engineers” – newly evolved biological organisms that altered the environment so radically it drove older species to extinction.

The event, known as the end-Ediacaran extinction, took place 540 million years ago. The earliest life on Earth consisted of microbes – various types of single-celled organisms. These held sway for more than 3 billion years, when the first multicellular organisms evolved. The most successful of these were the Ediacarans, which spread around the globe about 600 million years ago. They were a largely immobile form of marine life shaped like discs and tubes, fronds and quilted mattresses.

After 60 million years, evolution gave birth to another major innovation: metazoans, the first animals. Metazoans could move spontaneously and independently at least during some point in their life cycle and sustain themselves by eating other organisms or what other organisms produce. Animals burst onto the scene in a frenzy of diversification that paleontologists have labeled the Cambrian explosion, a 25 million-year period when most of the modern animal families – vertebrates, mollusks, arthropods, annelids, sponges and jellyfish – came into being.

“These new species were ‘ecological engineers’ who changed the environment in ways that made it more and more difficult for the Ediacarans to survive,” said Simon Darroch, assistant professor of earth and environmental sciences at Vanderbilt University, who directed the new study described in the paper titled “A mixed Ediacaran-metazoan assemblage from the Zaris Sub-basin, Namibia,” published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.

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It is the nature of all life to affect its environment. What makes our species exceptional, is our ability to recognize the consequences of our actions (and hopefully address them.)

It was only decades ago that the Cuyahoga river caught fire, repeatedly. http://clevelandhistorical.org/items/show/63 and it wasn’t alone! http://www.environmentalcouncil.org/priorities/article.php?x=264

We decided, eventually, that, maybe, that wasn’t a good thing™ and did something about it!

[TheBaculumKing]

1. Strangely

They seem to have largely republished a paper from 2015

http://news.vanderbilt.edu/2015/09/evidence-that-earths-first-mass-extinction-was-caused-by-critters-not-catastrophe/

Pre-existing life forms couldn't survive the toxic oxygen...

[OKIsItJustMe]

2. Here’s the difference

“With this paper we’re narrowing in on causation; we’ve discovered some new fossil sites that preserve both Ediacara biota and animal fossils (both animal burrows – ‘trace fossils’ – and the remains of animals themselves) sharing the same communities, which lets us speculate about how these two very different groups of organisms interacted,” he said.