What Triggers Mass Extinctions? Study Shows How Invasive Species Stop New Life

National Science Foundation ^ | December 29, 2010 | Unknown

[decimon]

An influx of invasive species can stop the dominant natural process of new species formation and trigger mass extinction events, according to research results published today in the journal PLoS ONE.

The study of the collapse of Earth's marine life 378 to 375 million years ago suggests that the planet's current ecosystems, which are struggling with biodiversity loss, could meet a similar fate.

Although Earth has experienced five major mass extinction events, the environmental crash during the Late Devonian was unlike any other in the planet's history.

The actual number of extinctions wasn't higher than the natural rate of species loss, but very few new species arose.

"We refer to the Late Devonian as a mass extinction, but it was actually a biodiversity crisis," said Alycia Stigall, a scientist at Ohio University and author of the PLoS ONE paper.

"This research significantly contributes to our understanding of species invasions from a deep-time perspective," said Lisa Boush, program director in the National Science Foundation (NSF)'s Division of Earth Sciences, which funded the research.&

"The knowledge is critical to determining the cause and extent of mass extinctions through time, especially the five biggest biodiversity crises in the history of life on Earth. It provides an important perspective on our current biodiversity crises."

The research suggests that the typical method by which new species originate--vicariance--was absent during this ancient phase of Earth's history, and could be to blame for the mass extinction.

Vicariance occurs when a population becomes geographically divided by a natural, long-term event, such as the formation of a mountain range or a new river channel, and evolves into different species.

New species also can originate through dispersal, which occurs when a subset of a population moves to a new location.

In a departure from previous studies, Stigall used phylogenetic analysis, which draws on an understanding of the tree of evolutionary relationships to examine how individual speciation events occurred.

She focused on one bivalve, Leptodesma (Leiopteria), and two brachiopods, Floweria and Schizophoria (Schizophoria), as well as a predatory crustacean, Archaeostraca.

These small, shelled marine animals were some of the most common inhabitants of the Late Devonian oceans, which had the most extensive reef system in Earth's history.

The seas teemed with huge predatory fish such as Dunkleosteus, and smaller life forms such as trilobites and crinoids (sea lilies).

The first forests and terrestrial ecosystems appeared during this time; amphibians began to walk on land.

As sea levels rose and the continents closed in to form connected land masses, however, some species gained access to environments they hadn't inhabited before.

The hardiest of these invasive species that could thrive on a variety of food sources and in new climates became dominant, wiping out more locally adapted species.

The invasive species were so prolific at this time that it became difficult for many new species to arise.

"The main mode of speciation that occurs in the geological record is shut down during the Devonian," said Stigall. "It just stops in its tracks."

Of the species Stigall studied, most lost substantial diversity during the Late Devonian, and one, Floweria, became extinct.

The entire marine ecosystem suffered a major collapse. Reef-forming corals were decimated and reefs did not appear on Earth again for 100 million years.

The giant fishes, trilobites, sponges and brachiopods also declined dramatically, while organisms on land had much higher survival rates.

The study is relevant for the current biodiversity crisis, Stigall said, as human activity has introduced a high number of invasive species into new ecosystems.

In addition, the modern extinction rate exceeds the rate of ancient extinction events, including the event that wiped out the dinosaurs 65 million years ago.

"Even if you can stop habitat loss, the fact that we've moved all these invasive species around the planet will take a long time to recover from because the high level of invasions has suppressed the speciation rate substantially," Stigall said.

Maintaining Earth's ecosystems, she suggests, would be helped by focusing efforts and resources on protection of new species generation.

"The more we know about this process," Stigall said, "the more we will understand how to best preserve biodiversity."

The research was also funded by the American Chemical Society and Ohio University.

-NSF-

Media Contacts Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov Andrea Gibson, Ohio University (740) 597-2166 gibsona@ohio.edu

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2010, its budget is about $6.9 billion. NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives over 45,000 competitive requests for funding, and makes over 11,500 new funding awards. NSF also awards over $400 million in professional and service contracts yearly.

[grey_whiskers]

We have sold the industrial base for a number of reasons, each one from one or more traitorous groups with dovetailing nefarious interests.

The Dems hate America, and want a multi-polar world, and love Communism, as they fondly imagine that they will be among the surviving Kommisars instead of the first ones against the wall.

The industrialists want cheaper costs, less litigation and red tape, escape from unions, and *growth*. Which means they got all excited about the Demographics of the Third World, and realized that in order to sell to the Third World, they had to send gobs of money over there. Nice dovetail; except that much of the Third World, not having the memory of a Christian worldview filtered through a self-sufficient, politically independent middle class, took the money and created vast swaths of inequality instead.

(They don't notice that the 'savings' on labour are spread out throughout other areas not easily isolated to a single line-item).

China, India, and the rest get our jobs, our prestige, our money (trade deficit) and a hollowed-out U.S.

Then the "powers that be" decided, screw actually *producing* anything (as you pointed out): they can make more money on moving money around, profiting from price arbitrage, and on betting on *changes* in value. If you guess wrong, demand a bailout; if you guess right, you keep the money.

I think this dates to the mid-to-late 1970s and really took hold under Jack Welch and ilk in the 1980s, along with the cult-of-CEO-worship dating from that time. (And all the lower-level executives demanded commensurate increase in salary, perks, and status, as befitted aspiring-CEOs such as themselves.)

And some of it is good old fashioned robber-baron-style greed: Microsoft was sitting on $50 billion in CASH with no debt not too long ago (2003 or 2005 or so). By investing in US Treasuries (until recently, the "risk-free" return) they could have taken in $1 billion / year without jeopardizing the principal or the cash flow from continuing operations.

So any talk of going to India (as Brian Valentine said, "Think India! Two for the price of one!") was nothing but monstrous, inhuman greed on a scale to make Ebenezer Scrooge blush.

NO cheers, unfortunately. They are all scum.

[SunkenCiv]

The study of the collapse of Earth's marine life 378 to 375 million years ago suggests that the planet's current ecosystems, which are struggling with biodiversity loss, could meet a similar fate.

Thanks decimon. See, it's the fault of humans! IOW, no, I'm not buying into this. At least two of the global mass extinctions coincide with iridium layers from ET sources, and the AGW crowd (as well as the unreconstructed Darwinist teadrinkers) are forced to claim that the hard data is just a coinky-dinky. They're not doing science.

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[KoRn]

Very true.

The leftists always ignore the 500lb gorilla in the room, which is ‘death from above’, when it comes to discussion about what will ultimately ‘kill’ us. I suppose the reason that is, is because they can’t use the possibility of a comet striking the Earth as a means to manipulate people, extract wealth, or micromanage their lives.

[SunkenCiv]

· GGG managers are SunkenCiv, StayAt HomeMother, and Ernest_at_the_Beach · · join list or digest · view topics · view or post blog · bookmark · post a topic · subscribe ·
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[null and void]

Kudzu and coyotes!

[null and void]

#18

[SunkenCiv]

I’m just grateful it wasn’t a pic of you know who.

[null and void]

It is this lack of industrial power that is hurting us. And it will not come back. Ever.

Wanna bet?

[Hardraade]

The EPA is an invasive species.

[gleeaikin]

“The entire marine exosystem suffered a major collapse. Reef-forming corals were decimated.”

For this to happen I think that there must have been significant changes in water temperature, chemistry and oxygen content. The invasive species would then have multiplied and moved in on areas where less adaptable organisms died out. My guess is a large boloid event.

After the great dying of the Permian extinction event, Lystrosaurus, a piglike reptilian, was so abundant in South Africa “palaeontologists cry with frustration when they find another Lystrosaurus skull.” “it dominated the whole world for a short time...also from South America, Antarctica, India, China, Russia” [from “When Life Nearly Died: The Greatest Mass Extinction of all Time”, Michael J. Benton, 2003]

[steelyourfaith]

"The hardiest of these invasive species that could thrive on a variety of food sources and in new climates became dominant, wiping out more locally adapted species."

Before anthropogenic SUVs there were "new climates"? This is heresy to The Church of the Warming Globe, I reckon.

Thanx SunkenCiv !

 

Beam me to Planet Gore !

[SunkenCiv]

/bingo

When mass extinctions have happened, they’ve led to the ascendancy of different taxa of critters either underrepresented in the previous fossil record, or arisen by accelerated mutation due to mutagenic effects of the impactor or impact by-products. Mutation is the only source of speciation, and that’s on a good day — mass extinction removes any remaining need (a psychological one, at best) for natural selection as the origin of species.

[SunkenCiv]

Thanks gleeaikin.

Asteroid 'destroyed life 250m years ago'
by Dr David Whitehouse
Friday, February 23, 2001

Earth's biggest mass extinction 251 million years ago was triggered by a collision with a comet or asteroid, US scientists say. They have reached this conclusion by looking at atoms from a star trapped inside molecular cages of carbon...

In rock layers laid down at the time, there is a much higher concentration of complex carbon molecules called fullerenes that have different types, or isotopes, of helium and argon trapped inside them. These molecules could only have been delivered from space, the researchers say...

The researchers believe these particular fullerenes are extraterrestrial because the gases trapped inside have an unusual ratio of isotopes that indicate they were made in the atmosphere of a star that exploded before our Sun was born...

The telltale fullerenes were extracted from sites in Japan, China and Hungary, where the sedimentary layer at the boundary between the Permian and Triassic periods had been exposed...

The research was made difficult because there are few 251-million-year-old rocks left on Earth. Most rocks of that age have been recycled through the planet's tectonic processes...

Researchers estimate the comet or asteroid was six to 12 km (3.7 - 7.4 miles) across, or about the size of the asteroid believed responsible for the extinction of the dinosaurs 67 million years ago...

The mass extinction of 251 million years ago was the greatest on record.

[chesley]

What’s the plan? I’m in.

[null and void]

First we kill all the lawyers...

[AndrewC]

In addition, the modern extinction rate exceeds the rate of ancient extinction events

That's because presently there are idiots that claim something is a new species at the drop of a hat. A species whose total population is one, has a very dim future.

[SunkenCiv]

My pleasure, Happy New Year steelyourfaith!

[wolfcreek]

You got it!

[Domestic Church]

Death by kudzu!