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Study turns back clock on origins of life on Earth

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DazzaMc
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« on: May 29, 2009, 11:08:45 am »

CHICAGO, May 20, 2009 (Reuters) — A heavy bombardment by asteroids the size of Ireland was not enough to wipe out life on Earth 3.9 billion years ago, researchers said on Wednesday in a finding that turns back the clock of life by 500 million years

Many scientists had thought the violent pelting by massive asteroids during the period known as the Late Heavy Bombardment would have melted the Earth's crust and vaporized any life on the planet.

But new three-dimensional computer models developed by a team at the University of Colorado at Boulder shows much of Earth's crust, and the microbes living on it, could have survived and may even have thrived.

"These new results push back the possible beginnings of life on Earth to well before the bombardment period 3.9 billion years ago," said Oleg Abramov, a researcher at the university whose study appears in the journal Nature.

"It opens up the possibility that life emerged as far back as 4.4 billion years ago, about the time the first oceans are thought to have formed," Abramov said in a statement.

To study this period, Abramov and colleague Stephen Mojzsis used data from moon rocks, meteorite samples and the dented surfaces of neighboring planets to develop a three-dimensional model of this period of bombardment.

"What we did was recreate the Late Heavy Bombardment on a computer," Abramov said, adding that the simulation randomly "smacked the Earth" with giant asteroids.

The team then looked at the impact that would have had on the Earth's temperature in the so-called geophysical habitable zone -- a zone representing the top 2.5 miles of the Earth's crust.

Based on these models, Abramov said this sustained period of impacts would have killed any life on the Earth's surface, but not all life on Earth, as many had assumed.

"We find it is essentially impossible to sterilize the entire habitable zone of the Earth by this kind of bombardment," Abramov said in a telephone interview.

"Certainly, the surface of the Earth was sterilized repeatedly," he said.

But he said hydrothermal vents below the surface of the Earth may have offered sanctuaries for certain heat-loving microbes, and may have even provided a kind of incubator for life.

He said many scientists had thought that a cataclysmic bombardment event would have sterilized the planet and life would have had to start anew.

"The important thing about these results is they push back the possible beginnings of life as we know it," he said.

"Exactly when life originated on Earth is a hotly debated topic," said Michael New, an astrobiologist at the National Aeronautics and Space Administration, which sponsored the research.

"These findings are significant because they indicated life could have begun well before the Late Heavy Bombardment, during the so-called Hadean Eon of Earth's history 3.8 billion to 4.5 billion years ago," New said in a statement.

http://www.newsdaily.com/stories/tre54j5px-us-asteroids/
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DazzaMc
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« Reply #1 on: May 30, 2009, 08:39:41 am »

Life on Earth May Have Begun Much Earlier

May 20, 2009 -- Life on Earth may have sparked into existence as early as 4.4 billion years ago, hundreds of millions of years sooner than previously thought possible, according to a study to be published Thursday.

Until now scientists assumed that no life forms could have survived the so-called Late Heavy Bombardment, a 100-million-year fusillade during which our young planet was pummeled by meteorites that blasted craters the size of Thailand and France.

All told, some 200 million billion tons of space rock rained down on the planet, according to the new study.

Heat generated by this relentless pounding was intense enough to melt much of Earth's surface, rendering it uninhabitable even for primitive life forms that thrived at high temperatures.

That, at least, has been the conventional wisdom, bolstered by the fact that the earliest traces of life discovered so far appeared shortly after the extraterrestrial onslaught tapered off 3.9 billion years ago.

Fossils reveal microscopic life forms 3.5 billion years old, and geochemical clues point to more primitive organisms -- thought by some to be the common ancestor to all things living -- 300,000 million years before that.

But Stephen Mojzsis and Oleg Abramov of the University of Colorado argue that early Earth wasn't so hellish after all.

Many life forms that might have arisen earlier could well have survived the bombardment, according to their study, published in Nature.

Using numerical models of impact-generated heat in Earth's crust, they show that no more than 37 percent of the planet's surface was sterilized at any given time, and that only 10 percent reached temperatures above 500 degrees Celsius (930 degrees Fahrenheit).

That is very hot, but much of Earth was cool enough to accommodate different families of microbes able to take the heat, 20C to 50C (70F to 120F) for some, and beyond the boiling point -- up to 110C (230F) -- for others.

Some microbes would also have been able to live several kilometers below Earth's surface, much as some simple life forms do today, the study points out.

"Our analysis shows that there is no plausible situation in which the habitable zone was fully sterilized on Earth," said Mojzsis.

"All the criteria necessary for life" -- liquid water, energy sources such as sunlight, and chemical building blocks from meteors or Earth itself -- "were present at least since 4.38 billion years ago," he said by e-mail.

"The antiquity of life may not be very much less than the Earth itself," he said.

Research published last week shows how a series of chemical reactions on early Earth could have produced ribonucleic acid, or RNA, a single-stranded cousin of the DNA that is the blueprint for all life.

Pushing back the date at which self-replicating life forms first emerged from the primordial soup would also explain how the relatively complex organisms that fossils records show existed 3.5 to 3.8 billion years ago could have had time to evolve.

In a commentary, also published in Nature, Lynn Rothschild of the NASA Ames Research Center in California says the new study convincingly shows how life may have emerged sooner rather than later.

"Moreover, it opens the possibility that life arose on Earth only once, and that the planet has been continuously inhabited ever since," she said.

Mojzsis is less inclined to think that everything within the realm of biology can be traced back to a single so-called "last universal common ancestor," or LUCA.

"Instead, they might have been a community of co-evolving proto-organisms that crystallized into a population" of primitive cells, he said.

Answering once-and-for-all the question of whether life happened more than four billion years ago will be extremely difficult, scientists say.

So much of the evidence -- if there is any -- was destroyed during Earth's fiery baptism that finding intact traces may be futile. The earliest sedimentary rock ever found is "only" 3.83 billion years old.

http://dsc.discovery.com/news/2009/05/20/early-earth-life.html


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Sir Blodsnogger
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« Reply #2 on: October 13, 2009, 03:49:39 am »

This is a typical proof of scientific shenanigans about evidence/proof in support of the much vaunted evolution guess.

Life on Earth May Have Begun Much Earlier

Yes and the moon may be made of cheese too!
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robman
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« Reply #3 on: October 13, 2009, 05:02:35 pm »

Now you're being plain silly. We know the moon isn't made of cheese, we have rock samples.
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Sir Blodsnogger
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« Reply #4 on: October 14, 2009, 03:19:42 am »

Why do most evolutionist headlines include the word MAY have
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« Reply #5 on: October 14, 2009, 07:42:25 pm »

Because there are constantly new developments and they're being honest. There's no way an honest scientist will say that everything is known about that particular subject.
I have a slightly jaundiced view of some of the claims that get made, to be honest but that doesn't mean I believe the whole theory is wrong.
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« Reply #6 on: October 15, 2009, 01:50:50 am »

At last someone has a balanced view on the topic.
My beef has been that all theories are promoted by dazza as being facts. And that is impossible in my view.
But dazza cant understand that so he prefers to dump someone who disagrees with his take on the world.
He should not be using his role in here to get rid of open debate/argument and irritating commentary.
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pantherrr0
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« Reply #7 on: October 15, 2009, 07:21:10 am »

i dont think he's done anything like that at all gom.  moved some waffles around perhapes =)
i guess he might just have been expecting a  medium to high level of debate. you know  backed up by references and something testable.
what your doing is trying to  discredit things with no basis of objection other than it doesnt align with whatyou belive in.
whats more you cant even provide any evidence what so ever of an alternative. ^^ most of the  so called counter arguments taht you copy and paste from who knows where  have gaping holes in them.
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DazzaMc
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« Reply #8 on: October 15, 2009, 03:09:36 pm »

i dont think he's done anything like that at all gom.  moved some waffles around perhapes =)
i guess he might just have been expecting a  medium to high level of debate. you know  backed up by references and something testable.
what your doing is trying to  discredit things with no basis of objection other than it doesnt align with whatyou belive in.
whats more you cant even provide any evidence what so ever of an alternative. ^^ most of the  so called counter arguments taht you copy and paste from who knows where  have gaping holes in them.

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« Reply #9 on: October 16, 2009, 05:29:51 pm »

Why do most evolutionist headlines include the word MAY have

That is as Rob pointed out, because there is always new information coming out thru the study of fossils etc, the study/ science of evolution etc is not a static blind dogma that is closed to information that may make what we believe/ been taught by a preacher/ pastor/ priest/ minister incorrect like christianity and/ or creationlism.
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R. S. OhAllmurain
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« Reply #10 on: October 17, 2009, 06:09:04 am »

i dont think he's done anything like that at all gom.  moved some waffles around perhapes =)
i guess he might just have been expecting a  medium to high level of debate. you know  backed up by references and something testable.
what your doing is trying to  discredit things with no basis of objection other than it doesnt align with whatyou belive in.
whats more you cant even provide any evidence what so ever of an alternative. ^^ most of the  so called counter arguments taht you copy and paste from who knows where  have gaping holes in them.

I think then that you would be quite happy if he moved any of your waffles around would you?
Or does that only apply to me.
No he is a little bully hiding behind his badge. He'd make a good third world cheating premier. They are all in to fraud and corruption AND they bury their oppostion. A bit like Hitler's silencing of the press.
He is a crook and a charlatan who has not an ounce of honesty or integrity in him.
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« Reply #11 on: October 18, 2009, 10:50:28 am »

*shrug*  wouldnt care gom if it was off topic such as this  post  and  your post that im replying to is. Essentially Gom this part of the board was meant for science,  and yes opposition is a good thing providing its focused. The things here you will find are based on theory and  evidence as ive said before your so called objections  are not. in which case they dont fit in here.  rather you come in and by all appearances seem to want to cause trouble, degenerate down to name calling and offer little if anything that all that positively contributes to this section of the forums.
=)  to break it to something you may understand, your not likely to expect  sections about the prophet Muhammad  in every single chapter of your bible. In fact i believe you would stop reading it.
 The same goes for this, people open the thread read the the first  post then there it is a post by gommie that is either off topic, completely obscure, attacking some one or some sort of objection with out any basis to object from.
Now  you may be brilliant and actually have some valid arguments to present. If so please feel free to post them providing you keep it in context give references and if it is your OPINION then say so , but also say why it is that you believe this.
Personally Gommie im disappointed for some one that seems to show such strong faith in Christianity you set  a very bad example. Your behaviour and personal attacks in light your Your gods love thy neighbour  etc is very contradictory. Being unwilling to back up your statements or even understand any part of the topic your posting on does little towards convincing anyone that you have made an informed choice to follow your particular religious path. Whats more between those two issues from an outside perspective it seems that you offer little if anything positive to society in general i truly hope that the rest of the people that follow the same beliefs as you are more aware and live by a higher standard of ethics.
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« Reply #12 on: October 27, 2009, 04:03:42 am »

Thank you panther
So you prefer to attack a defenceless sensitive person such as my self rather than comment on my question about Dazza.
That is not understandable but it is sad.
Why do you think he should be above reproach in this? Are you the judge and jury appointed by dazza?

I repeat my comment here. Anychance of an answer old chap or are you goingto have another crack at character assasination?

'My beef has been that all theories are promoted by dazza as being facts. And that is impossible in my view.
But dazza cant understand that so he prefers to dump someone who disagrees with his take on the world.
He should not be using his role in here to get rid of open debate/argument and irritating commentary.'
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« Reply #13 on: October 27, 2009, 08:51:48 am »

Thank you panther
So you prefer to attack a defenceless sensitive person such as my self rather than comment on my question about Dazza.
That is not understandable but it is sad.
Why do you think he should be above reproach in this? Are you the judge and jury appointed by dazza?

I repeat my comment here. Anychance of an answer old chap or are you goingto have another crack at character assasination?

'My beef has been that all theories are promoted by dazza as being facts. And that is impossible in my view.But dazza cant understand that so he prefers to dump someone who disagrees with his take on the world.
He should not be using his role in here to get rid of open debate/argument and irritating commentary.'


You do the same with the bible gommie and many find that as impossible in their view, anyone who disagrees with you, you ridicule, barate (sp) and even go so far as to attack the culture, ancestroy and garb etc so you are no different at all! Tho I will say that you are less mature!
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R. S. OhAllmurain
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« Reply #14 on: October 27, 2009, 11:55:08 am »

i see the tickbird is awake and scrawled all over this again.
Lie down you dastardly white egret you.
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« Reply #15 on: October 27, 2009, 12:50:09 pm »

i see the tickbird is awake and scrawled all over this again.
Lie down you dastardly white egret you.

Go to hel you weasel you!
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R. S. OhAllmurain
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« Reply #16 on: October 29, 2009, 03:55:19 am »

Man's science is less factual than mathematics. Thats because buffoon scientists have the gall to use fairy tale stories to substantiate ridiculous theories.
Science exists in the minds of men (few women because women have more intellectual horsepower)
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« Reply #17 on: October 29, 2009, 08:40:39 am »

i think your missing the point  gom, all human  perception is in the mind, how ever with things like science the perception is not only shared  but  can be demonstrated and recognised by others. where as religion has no external  support baring story books, the perception is not fully shared nor can it be demostrated, the incosistancies give rise to the probability that most if not all  religious claims are something less pleasant than waffles. Again on our little planet here due to the relative mass  everything experiances a gravitational effect, in essence accelerating us "down" at aprox 9.81 m/s/s   i question if you have tried that experiment that i mentioned, i would hazard a guess at saying you hadnt.

 =)  while the origin of life is an interesting  subject another is where we are going to,  there is progressivly LESS educated people in the younger generation  being brainwashed into beliveing about you imaginary friend, how does it feel to be part of one of the last generations to mindless'ly believe in the bible ?
There is virtually no need for a god any more,  most of the  generic 'un known's " have been explained, all that remains is the  mental crutch aspect that some people seem to need. The 'crutch'  part has alot to do with kids being brain washed   and  churchs preying on the vunreable.
I Think the next big cultural evolution would be in terms of better support for the poor souls that believe in main stream religion,  something to educate them and show them that life witout the fairy tales is possible =)  probably to late to save you gom it seems ingrained but think if not your children or your  children's children  then the generation after could potentially religion free! how awesome is that!!  no more relgions wars no more more ingrained hatred due to religion, no more fear of science  think of the potential for addvancement with out  endless millions of people paying fundy idiots to stand around an preach bullshit!
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« Reply #18 on: October 29, 2009, 09:10:34 am »

Man's science is less factual than mathematics. Thats because buffoon scientists have the gall to use fairy tale stories to substantiate ridiculous theories.
Science exists in the minds of men (few women because women have more intellectual horsepower)
...and the Book of Genesus is accurate? LOL

Creationists Angry

It never occurs to them that rather than making every individual creature, animal or organism on this planet that it probably would have been much simpler just to create one such micro organism and let evolution solve most of the problems.

No, they have to take the Book of Genesis at face value. They have to believe that a story handed down orally for thousands of years before being written down and translated is the absolute and only truth dispite all the evidence to the contrary.

Do you really think that the ways of God are so simple that they could be understood by pre-literate man?

At least the scientists use the word "may" to show that what they are saying is far from completely comfirmed.

I appoligise for the religious rant but the flawed logic employed by creationists really gets my goat up.

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« Reply #19 on: October 29, 2009, 09:14:31 am »

Man's science is less factual than mathematics. Thats because buffoon scientists have the gall to use fairy tale stories to substantiate ridiculous theories.Science exists in the minds of men (few women because women have more intellectual horsepower)

About time you finally admitted that about fundy christian scientists gommie, tho calling them buffoons is really a little to harsh!
« Last Edit: October 29, 2009, 01:35:54 pm by AnFaolchudubh » Report Spam   Logged

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R. S. OhAllmurain
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« Reply #20 on: October 29, 2009, 12:11:29 pm »

Really?
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« Reply #21 on: October 29, 2009, 01:36:42 pm »

Really?

Yes... really!
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R. S. OhAllmurain
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« Reply #22 on: October 31, 2009, 11:57:36 am »

Noooooooo
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« Reply #23 on: November 01, 2009, 07:08:42 pm »

Blod old thing, there's a book I can recommend as giving a good overview of just how much science you can trust.
It's called A short history of nearly everything by Bill Bryson.
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Sir Blodsnogger
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« Reply #24 on: November 02, 2009, 12:01:07 am »

robbo that one must hold the record of being the world's shortest book.  Grin
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