Life coming to Earth from space ?

[John]

Interesting research and potential findings from a UK based team:

http://www.sheffield.ac.uk/news/nr/scientists-find-life-coming-to-earth-from-space-1.309972

[Naemeth]

I think it's likely life on Earth came from Mars. We just need to find the previous life on Mars to prove it .

[avtaram]

Very interesting article but isn't it the general concensus that water and molecular hydrocarbons with potential for developing into living organisms came with comets that bombarded the earth in the past.

Avtar

[John]

The article made me wonder if the arrival of life (albeit the most basic type) is a continuous process ?.

[m sutton]

Sir Fred Hoyle will one day be proved right in everything he ever said. From  Archeopteryx through Panspermia to the Steady-state Universe.

Oh my, can you imagine?

[astopy]

This research isn't really credible. See for example:

http://www.slate.com/blogs/bad_astronomy/2013/09/20/et_claims_of_alien_life_in_earth_s_atmosphere_are_unfounded.html

Basically, they don't appear to have made sure that what they found was actually a diatom, and even if it is it didn't necessarily come from space.

[Stu]

The article made me wonder if the arrival of life (albeit the most basic type) is a continuous process ?.

Interesting, and that's what the article implies too. If I had to bet anything significant on it I would expect that it will end up being an unknown mechanism for transportation of these particles from earth into the stratosphere but would love to be wrong!

I suppose one reason for doubt is that my understanding is that all life in earth starts from a single source ( I believe), would there not be bigger variations in DNA or types of fundamental life if it is coming from space?

All interesting stuff.

Stu

[Donkeiller]

"Of course it will be argued that there must be an, as yet, unknown mechanism for transferring large particles from Earth to the high stratosphere"

Yes, that is most likely correct.

There is much about the atmosphere and, indeed, the planet which we are ignorant of.

[GeoffE]

This research isn't really credible. See for example:

http://www.slate.com/blogs/bad_astronomy/2013/09/20/et_claims_of_alien_life_in_earth_s_atmosphere_are_unfounded.html

Basically, they don't appear to have made sure that what they found was actually a diatom, and even if it is it didn't necessarily come from space.

Phil Plait, self-appointed guardian of scientific virtue, has trashed the article by Wainwright et al. but are Plait's criticisms deserved?

Owing to the participation of N. Chandra Wickramasinghe in Wainwright's research and because Wickramasinghe has been mistaken on some issues in the past, Plait automatically dismisses any claims made in the Wainwright et al. paper.  Granted, Wickramasinghe has exhibited a predilection for finding diatoms in meteorites, but he has also published a substantial body of work in well-respected peer reviewed journals.  Whatever one might think about Wickramasinghe's work, he is but one of five coauthors.  Apparently, Plait's distrust of Wickramasinghe extends to all members of Wainwright's team.

Plait discredits the Journal of Cosmology because it is an online publication and has published papers which do not meet Plait's standards.  In my work, I've come across many papers in prestigious journals which I thought were abysmal examples of scientific research.  I do not see that the Journal of Cosmology, which is peer reviewed, is worse than average in this regard.  The peer review process is far from perfect.  I would also point out that, like the Journal of Cosmology, Plait's blog is an online publication.

Plait makes much of the identification of the diatom.  The authors wrote: "On one stub was discovered part of a diatom which, we assume, is clear enough for experts on diatom taxonomy to precisely identify."  They are clearly saying that the precise identification of the diatom by a diatom expert should be possible based on their photograph.  The authors know they are looking at a diatom which they tentatively classify as "a Nitzschia species."  In a rather sarky manner, Plait expresses doubt that the object is a diatom, and rebukes the authors for not getting a diatom expert to confirm that it is a diatom.  Plait is just being thick.

One gets the impression from Plait's complaints that the tone of the Wainwright et al. paper is reckless and adamant in its assertions.  That is simply not so.

I'm content to wait for follow-up research based on this initial finding.

Geoff

[Astrobits]

If life didn't originate on Earth but came here from Mars how can we be sure that Mars was the origin. Perhaps it arrived on Mars from somewhere else ( perhaps it came from Earth and then got sent back ?).

This is a circular argument that gets us nowhere.

We know that there are very primitive organisms in the early fossil records on Earth so why could life not have originated here?

Because "there is no known mechanism" for particles to be lifted to 27Km does not mean that they cannot be from Earth. We are often told by some scientists that Pollen from GM crops will not travel more than 50 or 100 meters so cannot cross fertilise with other plants but how often are our cars coated with "Sahara sand" blown in from a couple of thousand miles away?

Nigel

[Stargazer_00]

I think it's leftovers from the icelandic volcanic eruptions myself.  They say nothing significant within 3 years but who is to say who long particles can remain up there?

Non flying insects and even some smaller amphibians/animals can get carried across entire oceans just by air currents. 

[jnb]

"Of course it will be argued that there must be an, as yet, unknown mechanism for transferring large particles from Earth to the high stratosphere"

Yes, that is most likely correct.

There is much about the atmosphere and, indeed, the planet which we are ignorant of.

" Unknown"? Storm clouds can reach to altitudes of 20 km so where is the unknown?

[ShaunyC]

Suppose it would explain where new species come from!

[astopy]

Phil Plait, self-appointed guardian of scientific virtue, has trashed the article by Wainwright et al. but are Plait's criticisms deserved?

Not just Plait, but many others. A few examples:

• http://physicsfocus.org/louisa-preston-life-space-sadly-no/
• http://www.space.com/22875-alien-life-claim-space-microbes.html
• http://news.discovery.com/space/alien-life-exoplanets/invasion-of-the-high-altitude-alien-130920.htm

[Knight of Clear Skies]

Because "there is no known mechanism" for particles to be lifted to 27Km does not mean that they cannot be from Earth.

Nigel

This is the crux of the matter. In fact, there is at least one known mechanism for particles to be lifted to that altitude: they could have hitched a ride on the weather balloon carrying the experiment. Even if the balloon was completely sterilized at take-off, it's still going to pick up contaminants on its ride through the lower atmosphere. Diatoms are tiny algae, and among the most common forms of life on Earth. The one in question is a few millionths of a metre in length and you can find thousands in a single drop of water.

Panspermia is an interesting hypothesis worthy of consideration, but as such it requires proper investigation rather than grandiose claims built on highly suspect evidence.

[michael.h.f.wilkinson]

The Journal of Cosmology has a rather patchy record. In this case more specifically, there is ample evidence that the Nitzschia genus evolved here on earth. The fossil and genetic evidence is overwhelming. If Nitzschia lookalikes are raining down from on high at this moment, how does that explain the biochemical relationships between species on earth?  If this finding were correct, i.e., a creature with deep lineages on earth rained down from space just recently, this would suggest that the tree of life we have found on earth must have rained down in its entirety, elephants and all (or at least a significant portion of it. The claim just does not fit easily with the vast amount of knowledge we have of when certain species came into being on earth.

The claim that a diatom could not have been blown that high is wrong. Diatom frustules occur in many places, and could even be blown into the stratosphere by volcanic eruptions. It could even be contamination.

[GeoffE]

Not just Plait, but many others. A few examples:

• http://physicsfocus.org/louisa-preston-life-space-sadly-no/
• http://www.space.com/22875-alien-life-claim-space-microbes.html
• http://news.discovery.com/space/alien-life-exoplanets/invasion-of-the-high-altitude-alien-130920.htm

Astrobiologist Louisa Preston at physicsfocus.org wrote, "I wonder how many of you are reading this already reacting the way I did, simply thinking… 'is that it? You floated a balloon in the atmosphere for less than 20 minutes and one diatom fossil later you are screaming aliens?!'”  Wainwright et al. are not "screaming aliens."  Like Plait, Preston is spinning her account to make it sound as if the Wainwright et al. paper is riddled with zealous rhetoric.  This is not the case.

Preston also condemns the Journal of Cosmology:

"The paper was published in the Journal of Cosmology, an online freely available resource that is no stranger to controversial scientific claims. Its peer-review process has been called into question, and to be honest it has virtually no credibility within academia. The other red flag was that the research was conducted on July 31 2013, but the article was accepted for publication on August 9 2013. No scientist or journal in the world can pull off a turnaround time of 10 days, which raises eyebrows instantly as to the quality and accuracy of their findings."

Critics keep repeating that bit about the Journal of Cosmology being "an online freely available resource" as if this is ought to make one suspicious.  It may be news to many traditional academics, but online is the future, and free availability is what we should all be striving for insofar as restricted access to scholarship is not in the best interest of academe or humanity.

The criticism of the Journal of Cosmology's peer review process is fair so long as it is understood that this criticism applies to the peer review process of all academic journals.  Highly respected academic journals in every discipline have published papers that turned out to be incorrect and even fraudulent.  Educational psychologist Sir Cyril Burt is a famous case in point.  Evolutionary biologist Marc D. Hauser is another more recent example.  The claim that a peer review can't be done in ten days time is nonsense.  I've reviewed papers in my discipine within 24 hours of receipt.  Turnaround time depends on the length and complexity of the manuscript, selection of reviewers who do not procrastinate, and is facilitated by the internet.

Mike Wall (space.com) quotes Chris McKay (astrobiologist at NASA's Ames Research Center) who suggests that he would be convinced if analysis of the diatom shows that its biochemical makeup is inconsistent with Earth biochemistry.  And Wainwright et al. plan to do just this sort of analysis.  Wall goes on to say that astrobiologist Dirk Schulze-Makuch feels that Wainwright et al. should have done this kind of analysis before publishing their paper.  That's a fair criticism, and here we enter the realm of science reporting and human behaviour (scientists are, after all, human beings).  The question is to what extent do we hold Wainwright et al. responsible for the popular media reaction to their publication.  Their paper does not "scream aliens" but the authors can't control how others will react to their claim.  My reaction was that the paper was very interesting and that the follow-up analysis would either make or break them.  It would have been better (i.e., wise) had they postponed publication until the diatom was analyzed, but I quite understand the temptation.  There is intense pressure in academe to be first--no one remembers who was second in any discovery.  

Finally, Ian O'Neill (news.discovery.com) doesn't add anything new to the debate.  He criticizes Wainwright et al. for jumping to an alien origin conclusion based insufficient evidence and condemns the Journal of Cosmology.

Wainwright et al. have gambled that the diatom analysis will support their claim.  Again, I'm content to wait for their next report.  The hyperbolic reaction to their paper (for or against) is not appropriate in my estimation.

Geoff

[Liquid360]

What are your thoughts concerning symbiogenesis?

- Nate

Birmingham, AL

[michael.h.f.wilkinson]

Astrobiologist Louisa Preston at physicsfocus.org wrote, "I wonder how many of you are reading this already reacting the way I did, simply thinking… 'is that it? You floated a balloon in the atmosphere for less than 20 minutes and one diatom fossil later you are screaming aliens?!'”  Wainwright et al. are not "screaming aliens."  Like Plait, Preston is spinning her account to make it sound as if the Wainwright et al. paper is riddled with zealous rhetoric.  This is not the case.

Preston also condemns the Journal of Cosmology:

"The paper was published in the Journal of Cosmology, an online freely available resource that is no stranger to controversial scientific claims. Its peer-review process has been called into question, and to be honest it has virtually no credibility within academia. The other red flag was that the research was conducted on July 31 2013, but the article was accepted for publication on August 9 2013. No scientist or journal in the world can pull off a turnaround time of 10 days, which raises eyebrows instantly as to the quality and accuracy of their findings."

Critics keep repeating that bit about the Journal of Cosmology being "an online freely available resource" as if this is ought to make one suspicious.  It may be news to many traditional academics, but online is the future, and free availability is what we should all be striving for insofar as restricted access to scholarship is not in the best interest of academe or humanity.

The criticism of the Journal of Cosmology's peer review process is fair so long as it is understood that this criticism applies to the peer review process of all academic journals.  Highly respected academic journals in every discipline have published papers that turned out to be incorrect and even fraudulent.  Educational psychologist Sir Cyril Burt is a famous case in point.  Evolutionary biologist Marc D. Hauser is another more recent example.  The claim that a peer review can't be done in ten days time is nonsense.  I've reviewed papers in my discipine within 24 hours of receipt.  Turnaround time depends on the length and complexity of the manuscript, selection of reviewers who do not procrastinate, and is facilitated by the internet.

Mike Wall (space.com) quotes Chris McKay (astrobiologist at NASA's Ames Research Center) who suggests that he would be convinced if analysis of the diatom shows that its biochemical makeup is inconsistent with Earth biochemistry.  And Wainwright et al. plan to do just this sort of analysis.  Wall goes on to say that astrobiologist Dirk Schulze-Makuch feels that Wainwright et al. should have done this kind of analysis before publishing their paper.  That's a fair criticism, and here we enter the realm of science reporting and human behaviour (scientists are, after all, human beings).  The question is to what extent do we hold Wainwright et al. responsible for the popular media reaction to their publication.  Their paper does not "scream aliens" but the authors can't control how others will react to their claim.  My reaction was that the paper was very interesting and that the follow-up analysis would either make or break them.  It would have been better (i.e., wise) had they postponed publication until the diatom was analyzed, but I quite understand the temptation.  There is intense pressure in academe to be first--no one remembers who was second in any discovery.  

Finally, Ian O'Neill (news.discovery.com) doesn't add anything new to the debate.  He criticizes Wainwright et al. for jumping to an alien origin conclusion based insufficient evidence and condemns the Journal of Cosmology.

Wainwright et al. have gambled that the diatom analysis will support their claim.  Again, I'm content to wait for their next report.  The hyperbolic reaction to their paper (for or against) is not appropriate in my estimation.

Geoff

Wainright et al do scream "Aliens" in the very title of their paper: EVIDENCE OF COSMIC ORIGIN. As a scientist myself I am very reticent about making wild claims in the title (or abstract for that matter), because I know "science journalists" will jump on it instantly, and completely forget about any nuance I might have added later in the paper.

Let us assume their claim is valid: In that case they have done themselves no favours by jumping the gun, and publishing before they could properly verify (or falsify) their hypothesis. It does not feel like the authors tried to prove their pet theory wrong. Many scientists fail in that way, which is understandable.  It is very human not to try to kill your darlings, but it is what scientists should try to do at every turn.

Their argument that it could not be a contaminant from either the balloon or the lab workers cuts little ice: Diatoms are ubiquitous organisms found in practically any place with sufficient moisture (moss or wet grass will do: putting a balloon on the ground could be sufficient to pick up a couple). Nitzschia is mainly marine (cold water), but very similar species survive in puddles along any roadside. Besides, fossil Nitzschia specimens might be found anywhere on land. Diatomaceous earth is even used in certain laboratories for filtration purposes (including separation of DNA from RNA), it is used in certain toothpastes, and in dynamite. Plenty of sources of contamination, even if the fragment is not a residue from some volcanic eruption

[GeoffE]

What are your thoughts concerning symbiogenesis?

- Nate

Birmingham, AL

I think symbiogenesis is a very important development in evolutionary theory and I admire the work of Lynn Margulis and others who are pursuing work in this area.

Geoff

Geoff

[GeoffE]

Wainright et al do scream "Aliens" in the very title of their paper: EVIDENCE OF COSMIC ORIGIN. As a scientist myself I am very reticent about making wild claims in the title (or abstract for that matter), because I know "science journalists" will jump on it instantly, and completely forget about any nuance I might have added later in the paper.

Let us assume their claim is valid: In that case they have done themselves no favours by jumping the gun, and publishing before they could properly verify (or falsify) their hypothesis. It does not feel like the authors tried to prove their pet theory wrong. Many scientists fail in that way, which is understandable.  It is very human not to try to kill your darlings, but it is what scientists should try to do at every turn.

Their argument that it could not be a contaminant from either the balloon or the lab workers cuts little ice: Diatoms are ubiquitous organisms found in practically any place with sufficient moisture (moss or wet grass will do: putting a balloon on the ground could be sufficient to pick up a couple). Nitzschia is mainly marine (cold water), but very similar species survive in puddles along any roadside. Besides, fossil Nitzschia specimens might be found anywhere on land. Diatomaceous earth is even used in certain laboratories for filtration purposes (including separation of DNA from RNA), it is used in certain toothpastes, and in dynamite. Plenty of sources of contamination, even if the fragment is not a residue from some volcanic eruption

Try as I might, I still can't detect screaming in the Wainwright paper.  Your hearing is more sensitive than mine.  And I don't quite see their claim as being wild.  Perhaps it comes from the discovery of life in some of the most unexpected and inhospitable places.  Extremophiles make me think that life is difficult to prevent.  It may well be that sterility is the extraordinary condition.

As for premature publication and other missteps by fellow scientists, it appears that I'm willing to tolerate a good deal more of this than most.

Your point about the ubiquity of diatoms is well taken.  The analysis of the diatom may settle the argument (at least temporarily).  Extraterrestrial origin is a long shot to be sure, but I can't help hoping that they've got it right.

Geoff

[Liquid360]

If some of those basic ingredients Necessary for intelligent life came from Mars while other ingredients came by way of comets, it certainly complicates the search for other intelligent life. The question then becomes what would the earth be like without mars' contributions.

- Nate

Birmingham, AL

[michael.h.f.wilkinson]

Try as I might, I still can't detect screaming in the Wainwright paper.  Your hearing is more sensitive than mine.  And I don't quite see their claim as being wild.  Perhaps it comes from the discovery of life in some of the most unexpected and inhospitable places.  Extremophiles make me think that life is difficult to prevent.  It may well be that sterility is the extraordinary condition.

As for premature publication and other missteps by fellow scientists, it appears that I'm willing to tolerate a good deal more of this than most.

Your point about the ubiquity of diatoms is well taken.  The analysis of the diatom may settle the argument (at least temporarily).  Extraterrestrial origin is a long shot to be sure, but I can't help hoping that they've got it right.

Geoff

The do scream in the title: they claim EVIDENCE OF COSMIC ORIGIN in the title, without presenting any clear cut evidence. In scientific terms that is shouting at the top of your voice. Do not get me wrong, if they had presented really convincing evidence, I would have applauded their paper, and been as excited as the next person (probably a lot more so, knowing my near limitless supply of enthusiasm). I am not at all opposed to the idea that early forms of life may have arrived from elsewhere and have evolved here. New arrivals might be coming in, but the paper just does not make a good case for it, but still puts it forward in title.

The situation with symbiogenesis is very different. There is solid evidence that mitochondriae and chloroplasts started out as endosymbionts. The main contention in that area is whether symbiogenesis is the main driving force behind evolution as opposed to competition and speciation (as in the classical synthesis). In my opinion that discussion is a bit pointless. It is clear both processes occur. Symbiogenesis is probably more important in simpler organisms than in multicellular ones, but there is evidence of viral DNA being embedded in our genes as well. 

[Liquid360]

Great response! I couldn't agree more... obvious by my "great response" sentence prior. The Mars info is just a VERY early though, brought on by the discovery of water. I had heard talk of amino acids but I could be wrong.

I've been somewhat surprised by the lack of discussion concerning symbiogenesis.

It seems to me it should be a BIG DEAL. I agree with your belief that one doesn't in anyway disprove the other. Obviously competition is a driving force but so far as "the big picture" goes, I'm far more interested in the idea that symbiogenesis is the primary driving force behind biology and competition is simply a tool. It seems to me that over time we'll figure this out. It's unlikely we'll ever get the whole black hole singularity problem worked out but this is a question I believe we'll answer, not in our lifetime but eventually, and it's one of the big ones.

The do scream in the title: they claim EVIDENCE OF COSMIC ORIGIN in the title, without presenting any clear cut evidence. In scientific terms that is shouting at the top of your voice. Do not get me wrong, if they had presented really convincing evidence, I would have applauded their paper, and been as excited as the next person (probably a lot more so, knowing my near limitless supply of enthusiasm). I am not at all opposed to the idea that early forms of life may have arrived from elsewhere and have evolved here. New arrivals might be coming in, but the paper just does not make a good case for it, but still puts it forward in title.

The situation with symbiogenesis is very different. There is solid evidence that mitochondriae and chloroplasts started out as endosymbionts. The main contention in that area is whether symbiogenesis is the main driving force behind evolution as opposed to competition and speciation (as in the classical synthesis). In my opinion that discussion is a bit pointless. It is clear both processes occur. Symbiogenesis is probably more important in simpler organisms than in multicellular ones, but there is evidence of viral DNA being embedded in our genes as well.

- Nate

Birmingham, AL

[michael.h.f.wilkinson]

Great response! I couldn't agree more... obvious by my "great response" sentence prior. The Mars info is just a VERY early though, brought on by the discovery of water. I had heard talk of amino acids but I could be wrong.

I've been somewhat surprised by the lack of discussion concerning symbiogenesis.

It seems to me it should be a BIG DEAL. I agree with your belief that one doesn't in anyway disprove the other. Obviously competition is a driving force but so far as "the big picture" goes, I'm far more interested in the idea that symbiogenesis is the primary driving force behind biology and competition is simply a tool. It seems to me that over time we'll figure this out. It's unlikely we'll ever get the whole black hole singularity problem worked out but this is a question I believe we'll answer, not in our lifetime but eventually, and it's one of the big ones.

- Nate

Birmingham, AL

For evolution to work you just need three ingredients:

- inheritance

- generation of inheritable variability

- selection pressure to select "the fittest"

I would say that there is proof of symbiogenesis, and proof of radiation of species through mutation/crossover. Both mechanisms provide inheritable variability, so both contribute to evolution. What is clear is that genes are often reorganized. Most of the genome of the early endosymbionts that became mitochondriae or chloroplasts was transferred to the (proto)-eukaryote nuclear DNA, where it benefited from better proof-reading mechanisms, decreasing the rate of mutation of these critical organelles. Part of this process can be understood in terms of the "Evolution of Evolvability", a phrase coined by Richard Dawkins in his article of that title in the proceedings "Artificial Life" of the Santa Fe Institute. Certain gene organizations evolve more easily than others, e.g., by keeping important bits of information, whilst allowing more rapid mutation of less critical bits, or quite simply keeping genes that are involved in related processes close together so that crossover does not easily clip apart good combinations of genes.

Complex matters that are often simplified too much in efforts to have one overarching theory.