Talk:Panspermia

From Wikipedia, the free encyclopedia

	Paranormal Portal This article falls under the scope of WikiProject Paranormal, which aims to build a comprehensive and detailed guide to the paranormal and related topics on Wikipedia. If you would like to participate, you can edit the attached article, help with current tasks, or visit the project page, where you can join the project and discussions.
B	This article has been rated as B-Class on the quality scale.

Contents 1 Recent Additions 2 Sci units 3 Day of the Triffids 4 Raelism 5 Evidence and mechanisms 6 Arrhenius and Panspermia 7 anthropic principle 8 Panspermia and Big Splash Theory 9 Glycine 10 Faulty Evidence 11 A Touch Optimistic? 12 Late Heavy Bombardment 13 Direct Evidence of Extraterrestrial Life 14 Changes 15 Animated Film 16 Theory or Hypothesis 17 Exogenesis 18 Suvival of life through asteroid impact 19 Main Article Link for Extremophiles? 20 Psuedo-science? 21 Red Rain 22 Horizon 23 Thoery Comment 24 UFO sightings 25 Stromatolites image 26 Change to introduction 27 Panspermia is not paranormal 28 etymology of the word "panspermia"? 29 Bacteria from high in the atmosphere 30 These scientific explanations only bring more questions... not answers 31 Not Exactly 32 Evidence of extraterrestrial life 33 Pop culture 34 References

[edit] Recent Additions

All of the recent additionsm, the cause of neutrality coming into question, have been reeditted by me to remove as much bias from the article as possible, while still having the research in the article. I can not help the fact that this subject is contraversial, but not a single thing added have i made up, they are all paraphrased from the following article:http://arxiv.org/ftp/astro-ph/papers/0312/0312639.pdf. The fact that the title, "New biology of red rain extremophiles prove cometrary panspermia." Would be an article to read, and paraphrase for discussion of the subject of panspermia. In the first paragraph of evidence, the opposite opinion on the red rain is now added, and referenced. I feel that I have made every attempt to give the information and maintain the neutrality of the issue.

[edit] Sci units

I don't recognise the time format "10s Ma" in the line "Dormant bacteria have been isolated from insects in amber 10s Ma old". Could this line be rewritten in way which is meaningful to a non-specialist audience? Alexjcharlton 21:55, 2 April 2007 (UTC)

[edit] Day of the Triffids

Citing Day of the Triffids as an example looks wrong to me. As far as I can recall the plot, the triffid seeds were a product of Soviet biotechnology that were accidentally released in the stratosphere. -- Alan Peakall 17:36 2 Jun 2003 (UTC)

In the movie adaptation they were from space.

[edit] Raelism

"One cannot help but notice the similarities between this hypothesis, and quasi-religious movements based on extraterrestial beings starting life on Earth, such as Raelism."

You should name some of these similarities, or it is just an opinion. - Omegatron 04:56, Jul 30, 2004 (UTC)

I think the Raelism connections and some of the other references in the SF section are probably wrong. Panspermia "is a narrower theory than 'life on Earth originated from outer space'. Specifically it is not the same as intentional colonisation by aliens. Rather panspermia is the hypothesis that the building blocks of life are common and uniform throughout space and that they take root when they land on a planet with suitable conditions. Directed panspermia, is that modification that the reason the building blocks are common would be due to the actions of a past alien civilisation. -- Solipsist 05:23, 30 Jul 2004 (UTC)

The two ideas are very similar, with some differences of course. Both advocate an external intelligent force behind the start of life, and transfer the problem of how life started (creator or not) somewhere else. Directed Panspermia make it random, and only providing seeds. Raelism says it is human only, and targeted to earth. Raelism relies on religious revelation for proof. Panspermia is a hypothesis that is so far unproven. We do not even know if intelligent extraterrestial life exists to begin with, let alone they actually did send the seeds of life. Raelism is advocated by someone who is considered fringe, and based on blind belief mostly. Panspermia is proposed by respected scientists. Other than these differences, you can see that they are pretty similar. Right? Can you see the similarity (and differences) now? Can we agree on a comment that can go back in the article? -- KB 19:07, 2004 Jul 30 (UTC)

Not really. I can see where you are coming from, but the word panspermia is created from the Greek : pan- "all" + sperma, "seed". If Raelism doesn't involve the idea of spreading the seeds of life uniformly throughout the universe it isn't panspermia, but alien colonisation. Panspermia is a serious scientific idea, even if it is not often taken seriously. The most important aspect about panspermia is its uniformity, implying that Earth is in no way special and if the hypothesis is true we would expect to frequently find the seeds of life on other planets, including the other planets of our solar system where DNA is not likely to be destroyed. In many ways it is an extension of the cosmological principle, and Fred Hoyle was so keen on removing the Earth from any special position in the universe that he never abandoned his Steady state theory because the big bang implies that we live at a special time in the history of the universe. -- Solipsist 19:36, 30 Jul 2004 (UTC)

If we were talking about mere panspermia, then we can agree. I agree that there are differences in what Raelism says and what Crick says. But Crick also talks about DIRECTED panspermia, which hypothesizes that some intelligent civilization INTENTIONALLY spread life throughout the universe. The existence of such intelligent civilzation, though quite plausible, has no proof whatsover. So how are we supposed to accept something scientifically that builds on something that has no scientific proof? I see that the scientific community applies double standards here, one for those inside it (e.g. Crick), and one to the outsiders (e.g. Raelians). I also see a problem with both the the directed panspermia hypothesis, and the Raelian approach (and other Alien Religions), because neither can be tested nor is reproducible to others. If one is not science, then the other is not. We have to be fair. -- KB 15:50, 2004 Aug 8 (UTC)

Yes you are right, there really is little evidence or proof in support of panspermia at the moment - its just an idea. Which is largely why it is a hypothesis rather than a theory and also why most of the scientific community isn't very interested in it. However, panspermia and directed panspermia would have specific consequences about the expected distribution of DNA or amino acids in the solar system and we are getting to the point where we can look for these. The Mars Exploration Rover Mission isn't equipped to look for organic molecules but future missions probably will. Raelism also makes predictions, specifically that once their embassy is constructed, Earth will be visited by extra-terrestrials and they will be about four feet in height. -- Solipsist 08:02, 9 Aug 2004 (UTC)

I'm no expert on Raelism. But from the article on it, it appears to be too intentional to be connected to directed panspermia. Directed panspermia is envisaged a last gasp effort from a civilisation facing extinction. If it is not cost efficient to launch a colonisation attempt, directed panspermia is a strategy to spread DNA in the hope that it will take root somewhere. -- Solipsist 19:01, 30 Jul 2004 (UTC)

I don't think so either. They both involve space and the origins of life on earth, but so do a lot of things. - Omegatron 19:51, Jul 30, 2004 (UTC)

I am now wondering whether we shouldn't have a section making the differences between panspermia and other ideas like Raelism more explicit. -- Solipsist 08:02, 9 Aug 2004 (UTC)

As I noted in the article, the word panspermia is starting to be used colloquially for any origin of life from outer space, which should properly be termed exogenesis. Exogenesis redirects to here, though, so maybe he has a point about the Raelism stuff being related. But only maybe. - Omegatron 01:33, Jan 10, 2005 (UTC)

[edit] Evidence and mechanisms

We should also include some "evidence against" bullets. - Omegatron 19:55, Jul 30, 2004 (UTC)

Agreed, but I am not sure there is any yet. As more of a hypothesis than a theory, panspermia is not easily falsifiable. I guess failing to find any evidence of microbial life on Mars, or Europa after extensive searches, would weaken the hypothesis. But that isn't going to happen any time soon. Theories or experiments which bridge the gap between the Urey-Miller experiment and self replicating DNA/RNA might shead new light on the origin of life and invalidate panspermia. -- Solipsist 10:21, 5 Aug 2004 (UTC)

[edit] Arrhenius and Panspermia

Astronomer Sir Fred Hoyle and his collaborator N. Chandra Wickramasinghe have built on the modern concept of panspermia set out by the 19th century chemist Svante Arrhenius.

Yes it looks like Arrhenius' theory on spores should be mentioned. This web site suggests several other proponents between Anaxagoras and Hoyle too, with the bibliography to back them up here. -- Solipsist 15:01, 5 Aug 2004 (UTC)

[edit] anthropic principle

" (not so unlikely under the anthropic principle), "

are you sure about that? the amount of time original life took to develop really doesn't have any bearing on the eventual existence of humans and wondering about their origins... so if it took dramatically faster than would be expected by chance, that is still a valid observation. - Omegatron 16:02, Dec 23, 2004 (UTC)

[edit] Panspermia and Big Splash Theory

Has anyone considered that life came from that Mars like planet that crashed into Earth to form the Moon around 4 billion years ago ?

I dont think its ever been properly explained where that Mars like planet came from. So i suppose its possible to suggest that little green men shot it at just the right angle and velocity to impact earth in just the right way without destroying it, as part of directed Panspermia to create M class planets and seed it with humanoids just like them.

And uh, i think Panspermia is part of the plot in the X files end of season where Mulder was taken.

Ps- if its not already obvious, im not a scientist. Just someone who watches too much tv. *smiles*

Is it widely accepted that Giant impact theory happened? Maybe it was a Generation ship. :-) - Omegatron 18:44, Jan 9, 2005 (UTC)

Yes and no - getting away from X-files speculation and the like, Giant impact theory is fairly credible for the formation of the moon and fits in with the general accretion picture for the formation of the solar system. On the other hand it is the sort of thing which is parallel to, or independent of any theory for the origin of life. Highly energetic events like this can be expected to destroy life if it had already started. Giant impact theory posits that the moon forming impact would have happened during the earliest stages of the formation of the solar system some 4.5 billion years ago. The earlist evidence of life on Earth is several million years after that. Panspermia would suggest that the seeds of life would already be around in the proto-solar system at that time. It may have taken hold on the early Earth, or the Mars size body that impacted it. Life could have be preserved or more likely destroyed, but in any case there would be enough organic material around in the early solar system that it would have reseeded the planets as soon as they had cooled enough for life to take root. -- 22:43, 9 Jan 2005 (UTC)

"e 4.5 billion years ago. The earlist evidence of life on Earth is several million years after that."

I am learning the actual numbers lately, and I think life is supposed to have originated 2 billion ago. - Omegatron 01:33, Jan 10, 2005 (UTC)

Is the data changing on this? Last I heard, the oldest evidence of life on Earth was Stromatolite fossils, dated at about 3.5 billion years old (for example [1]). -- Solipsist 22:30, 21 Jan 2005 (UTC)

I have no idea. - Omegatron (NOT A GEOLOGY EXPERT. DON'T LISTEN TO HIM.)

Have you ever wondered, that if life came to Earth from another planet, where did that life become of.

[edit] Glycine

> In 2002, the discovery of glycine (the simplest amino acid) in interstellar clouds lends additional support.

This reference is in a contradiction with the glycine article, which states that Yi-Jehng Kuan did not made such discovery.

Well actually the glycine article says the Yi-Jehng Kuan result is being contradicted in a yet to be published paper by Lewis Snyder et al. As such it is probably too early to say either way. But if the Yi-Jehng Kuan result is potentially in doubt, the statement should be qualified in this article too. -- Solipsist 22:22, 21 Jan 2005 (UTC)

To the extent that the discovery of amino acids in interstallar clouds adds to the plausibility of panspermia, it also removes one of the supports for the idea, that it's unlikely for life to have started as quickly on Earth as it seems to have done. Given that organics are around in space, they would have been available pre-formed on early Earth, making abiognenesis more likely, easier for life to start 'by chance'.Davy p 04:26, 17 November 2006 (UTC)

[edit] Faulty Evidence

The glycine bullet was indeed in contradiction with the glycine article. In addition, the ALH84001 bullet was in contradiction with the ALH84001 article and the red rain bullet has been refuted by further scientific investigation. I have edited the page accordingly. Given that these instances of "evidence" for panspermia have been debunked, it might be more appropriate to use them as examples discounting panspermia in the objections section or to at least move them out of the direct evidence category. At present the objections section is pretty weak given that the theory of panspermia is a contentious issue in the scientific community with no true direct evidence. I would suggest that contributers do more thorough fact checking before making posts on issues of this sort. Wikipedia does not need to be labeled as a host to pseudoscience. I find the cryptozoology articles much more balanced in this respect. -- Mark 20:58, 27 Feb 2005 (UTC)

Thanks for fixing it. That's the whole point. - Omegatron 04:48, Feb 28, 2005 (UTC)

[edit] A Touch Optimistic?

(Original talk page comments in bold italics)

I think this article needs to be a lot more skeptical regarding the issues at hand. The evidence isn't really evidence: the conditions that allow for panspmeria are described, but it's actually having occured on Earth is nowhere supported. It isn't emphasized that panspmeria is quite a minority opinion and objections to the idea are not seriously raised. Marskell

We should also include some "evidence against" bullets. - Omegatron 19:55, Jul 30, 2004 (UTC)

Agreed, but I am not sure there is any yet. As more of a hypothesis than a theory, panspermia is not easily falsifiable.

The most obvious evidence against is the enormous time it requires for ejecta from bodies outside the solar system to reach Earth and the extremely slim chance of any micro-biotic criters surviving. Imagine a comet flying in from Alpha Centauri at 1% light speed (a generous estimate): 400 hundred plus years to get here and then, of course, the body must find it's way to Earth and anything still alive must survive Earth-entry and subsequently propogate. Marskell

If circumstantial evidence that allows panspermia "isn't really evidence", then your evidence that disallows it isn't really evidence, either. Besides, these things are addressed in the article. - Omegatron 18:35, Apr 11, 2005 (UTC)

A second objection is based on Occam's Razor, which states that when multiple explanations are available for a phenomenon, the simplest version is preferred. It is not so clear that geogenesis is to be preferred over exogenesis under this rule.

Really?! I’ll assume I was born of the woman who raised me until I find evidence to the contrary! ;) Marskell

I don't see how this is a good analogy. - Omegatron 18:35, Apr 11, 2005 (UTC)

The former eliminates the step of transferring life across space, but requires a lot to happen in a relatively short time frame. If that short time frame is typical and not an aberration, life in general (including intelligent life) should be common in the universe, raising the Fermi paradox: Where are they?

First, as a matter of basic common sense Occam’s Razor dictates geogensis ahead of exogensis. The latter requires two steps: origin off Earth and subsequent transmission, while the former requires only one—in a short time fine, but 700 million to 1 billion years is longer, even in geologic terms, than this article makes out (about 5% of the universe’s overall age, which ain’t bad).

Secondly, panspmeria and exogensis foreground Fermi’s Paradox more strongly than geogensis. If Earth-life was seeded off Earth, after all, we should expect to find quite a lot of extraterrestrial activity. Marskell 17:47, 11 Apr 2005 (UTC)

How would we measure this activity? - Omegatron 18:35, Apr 11, 2005 (UTC)

I'm not sure it is worth arguing the points individually, but Marskell's basic comment that the article doesn't make it clear that Pansermia is _not_ a mainstream theory is valid. In reality, Panspermia is an interesting idea that is waiting in the wings for more corroborating evidence. Its stock would rise significantly if evidence of life was found somewhere else in the solar system, or (less likely) if hard limits were placed on the spontaneous creation of life which made it very unlikely to have first occured on Earth.

It would be worth updating the opening para to make this clear. -- Solipsist 19:36, 11 Apr 2005 (UTC)

[edit] Late Heavy Bombardment

I've changed this section somewhat.

• It is very unlikely the Earth was not affected to a similar or greater extent to the Moon, as they are very close and the Earth's greater gravitational field would likely attract more impactors. Also there is further evidence that the event was felt throughout the inner Solar System (Kring & Cohen 2002, although I could get hold of the full article).

• The likelihood is that the LHB was so intense that the surface was sterilised. Cohen (2000) suggests 100x impact rate. The situation for hydrothermal vents is not so clear cut, but possible these were sterilised too. If not, this may expand the window for a hydrothermal origin.

The upshot is a much shorter window for life to emerge. I've noted several alternatives, the upper of which is really rock-solid (formation of earth => first stromatolites). The Isua 13-C signal is under doubt because the rocks have been metamorphosed, and the signal is somewhat different to later rocks.

I'm not sure though that you can really count this as an argument - even circumstantial - for exogenesis when we know so little of the mechanisms behind the emergence of life. Maybe life doesn't take very long to emerge in the right conditions, and even 100Ma is plenty. If we *knew* that life took a long time to emerge, then the short time frame would be circumstantial evidence for exogenesis, but as we don't - does it really tell us anything? I suggest this entire section (i.e. narrow time window for geogenesis) go into Origin of Life as it is really more relevant there. It could still be mentioned here as a tenuously circumstantial pointer to exogenesis. What do you think?

Tonderai 16:48, 15 Apr 2005 (UTC)

I don't think you want to move timing arguments out of this page. As I understand it, whether it is relevant or not, the rapid appearance of life on Earth was one of the main impulses behind speculating about Panspermia. It is true, that Panspermia conjectures that the spontaneous creation of life is difficult and therefore rare. However this is a big unknown. The gap between the Miller-Urey experiment producing amino-acids and the development of RNA is a big chasm. But in time theoretical molecular biology might show that it is a chasm that is easy to cross. If so then the spontaneous creation of life is easy and Panspermia become largely irrelevant.

If it turns out that the chasm is difficult to cross, yet the evidence for primordial life is common throughout the solar system, then Panspermia becomes plausible. Conversely, if Earth is the only planet to show evidence of life, then Panspermia is largely invalidated.

The fact that life appears on Earth very shortly after it become possible to support it, is surprising. It suggests that either life is easy to get going, or something like Panspermia seeds every planet that is physically able to support life. -- Solipsist 20:53, 15 Apr 2005 (UTC)

You are right that amino-acids to life seems a huge chasm especially when you don't know how it happened. And it becomes even more surprising if you accept the LHB as a steriliser and the Isua C-13 fractionation - only 100Ma possibly! This seems a very short period of time for life to emerge, especially considering the several billion years before multicellular organsisms appeared. So you're right, a shorter window makes exogenesis more plausible unless we can show the process can happen very rapidly.

I think we await more evidence here, when you are dealing with plausibilities almost anything can go :)

Tonderai 22:23, Apr 15, 2005 (UTC)

This idea definitely needs a lot more evidence and is depends on a lot of unknowns, just like the origin of life. It should be presented as such, but shouldn't be dismissed or have parts removed because of this. - Omegatron 23:51, Apr 15, 2005 (UTC)

[edit] Direct Evidence of Extraterrestrial Life

There is as yet no definitive direct evidence of extraterrestrial life - this should be made clear.

• Two of the Viking biology experiments gave positive results. However the third showed there were no organic molecules in the Martian soil (organic molecules are widespread in similar terrestrial environments such as Antarctica). Subsequent experiments showed that the other two 'positives' could be reproduced using terrestrial clays. The results are generally accepted as being abiotically produced. To say 'official NASA stance' is rather conspiracy-theory-esque, in fact this is the general scientific consensus.

• Red rain point should be removed if it has been debunked.

• High altitude bacteria may show mixing from lower atmosphere or from space, but either supports panspermia as it shows either bacteria are present in space or can leave the lower atmosphere from Earth towards space. Keep this.

• Although the Glycine claim has been debunked, there are indeed a wide variety of organic molecules in interstellar space. This is significant for prebiotic chemistry, but not so for panspermia which requires viable lifeforms that are distinct from simple organics such as amino acids.

Btw thanks Omegatron for the spelling corrections! Tonderai 22:57, Apr 18, 2005 (UTC)

[edit] Changes

The introductory changes are very good--it reads much more critically now.

Omegatron, you're right to underscore my speculating after criticizing the article for being too speculative! I only used the example of a body coming from Alpha Centauri to put things in perspective. Life coming from Mars to Earth or vice versa could "hang-on" for the journey, but coming from another solar system (with a minimum window of a few centuries) it would need to reproduce and remain viable on the meteor itself. In terms of time frames a more realistic example is the voyager probes. Voyager 2 (still humming along at 3+ AU/year) will take 300 000 years to reach the neighbourhood of Sirius!

As for my analogy to motherhood I think you get the point: if I'm speculating about origins I'll assume the obvious unless other evidence jumps out at me. Marskell 04:06, 20 Apr 2005 (UTC)

[edit] Animated Film

There's a short (about two minute) wholly computer generated film by the name _Panspermia_ by Karl Sims from ca. 1991 that was quite entertaining and visually stunning, particularly for the time. I'm unable to find a definitive reference for it online. Wasn't sure how to link it into the main content in a reasonable fashion, so I'll leave it to wiser heads.

[judith.d] - i (re) added a link to it in Science Fiction. It had been removed by someone who claimed it was insignficant. In fact, it is one of the most influential works in the history of computer graphics animation.

[edit] Theory or Hypothesis

In this edit User:Thomqi comments If it's "unproven" then it's not "theoretical".

Well if it were proven it would actually be a "fact". In a scientific sense, all theories are unproven (you can find more about the relationship between theory and hypothesis at Scientific theories). However the concept of Panspermia is also largely untested and certainly not supported by a large body of evidence, so I don't object to the use of "Hypothesis". Others might. Panspermia is quite often refered to as a theory and it is testable. -- Solipsist 07:59, 8 December 2005 (UTC)

I have a theory that can explain "Panspermia" mechanism and why HERVs(human endogenous retrovirus - many chunks of viral DNA in our own genomes) exists, why viruses and prophages exist and what are they for, how mitochondrion and chloroplast came up, why MHC (major histocompatibility complex) is needed ... and it's quite simple ...the theory P.S. Readers have to be more knoledgable of what "Archaea" is 70.121.31.184 00:59, 28 March 2006 (UTC)

That's fine, but Wikipedia doesn't support original research — see Wikipedia:No original research. If this were published in a scientific journal it could be referenced. -- Solipsist 07:05, 28 March 2006 (UTC)

I apologize, I wasn't aware of that ...

[edit] Exogenesis

Shouldn't Exogenesis have its own article. Panspermia and directed panspermia are really subclasses, and I would have thought that exogenesis as a whole would include other theories of the origin of life being somewhere other than Earth. That ought to include non-scientific theories such as Raelism and I guess some of the ideas of Kurt Vonnegut.

Dictionary.com also lists Exogenesis as having an alternative meaning in medicine as being origin from external causes, as a disease, which is interesting as some of the original speculation on panspermia was in relation to the transmission of 'disease spores' from space. -- Solipsist 12:41, 7 January 2006 (UTC)

[edit] Suvival of life through asteroid impact

"...caused by asteroid impacts that affected the entire inner solar system. This is likely to have effectively sterilised Earth's entire planetary surface, including sbmarine hydrothermal systems that would be otherwise protected (Cohen et al., 2000)."

Some scientists speculate that life survived not in around hydrotherms, but rather by living deep under the surface of the earth. I believe studies of microbes found deep within mining excavations provides some evidence of this.

Sorry that I am unable to provide more specific details. Most of the above understanding comes from a US Discovery Channel show on this topic.

I saw the same show many times. Quite interesting, don't you think?

Lue3378 06:12, 1 February 2006 (UTC)

[edit] Main Article Link for Extremophiles?

Should there be one of those "Main Article: Extremophiles" for that section? If so, can someone do it? (Sorry, I don't know how and mayn't have time to learn.)

Now that I think of it, shouldn't that section be talking about procaryotes instead of simply bacteria? I added a small link to the archaea also - both they and bacteria make the procaryote branch - as they are typical extremophiles. As I can gather, this subject is rather touchy and recent in taxonomy, and would like the thoughts of others, possibly better-knowing than I, before I make these changes. FelisSchrödingeris 17:26, 10 March 2006 (UTC)

[edit] Psuedo-science?

I have a question, since the article doesn't seem to adress it: in the scientific community, how respected is the theory of panspermia? I would go far enough to call it psuedo-science since geogenesis makes much more sense and has more concrete evidence to support it. Can someone elaborate this for me, please?

I curious to know what evidence you think exists for geogenesis? --agr 10:35, 9 May 2006 (UTC)

The Miller-Urey experiments duplicated the early conditions of the Earth, and managed to prove that organic material could synthesize in the rich nitrogen, carbon, and oxygen atmosphere. I might be wrong, but this same process has been shown to occur in ocean volcanoes. BTW, I'm sorry if my first post was a little hostile, I just don't know of any respectable scientific groups that support panspermia.

Geogenesis is the most likely contender, but panspermia is not impossible. It may even happen elsewhere, but not here, or be spread from here (if that makes sense). Anyway, pseudoscience is the wrong term. Jefffire 09:18, 23 June 2006 (UTC)

Certainly not psuedo-science. In general I would characterise panspermia as an interesting contender, but not one that is easy to work on. The past support from heavy-weights like Fred Hoyle and Francis Crick means that panspermia tends to get treated respectfully, but a research scientist would probably struggle to get funding if they mentioned panspermia too directly in a research proposal. It is certainly possible to work on it in more narrow fields, such as looking for the spectral signature of organic compounds in space. Many of the solar system exploration missions that look for signatures of life would also help to place constraints on the likelyhood of panspermia, even though that wouldn't be their primary purpose. Carl Sagan is quoted as saying 'Extraordinary claims require extraordinary proof' and that would certainly apply to panspermia. At the moment we just have a few vague hints in support of the theory and are no where near extraordinary proof. -- Solipsist 10:04, 23 June 2006 (UTC)

The term is "fringe science". This may have been an alluring idea in the early space age of the 1950s-1970s, but not now. The hypothesis' currently fringy status absolutely needs to be noted prominently, per WP:FRINGE. I have the impression of pov-pushing here, since such statements have been repeatedly removed. dab (𒁳) 20:34, 18 September 2007 (UTC)

Sorry, but that category name is inherently POV. If you have a reputable source that calls panspermia fringe science, add it to the article. But category names are not a back door license for editorializing.--agr 20:50, 18 September 2007 (UTC)

I was going to ask the same question about this idea. Panspermia seems to be as much pseudoscience as ID. Or perhaps it's proto-science (nascent concepts)? I propose that this article be in the category:pseudoscience. However, I may be missing some important information. A concept posited for inquiry such as this is emergent but it seems much more imagination than testable in any way. Please provide evidence that validates that panspermia is not pseudoscience. Thank you. --Davidp (talk) 23:46, 20 April 2008 (UTC)

[edit] Red Rain

I've taken out a lot of dubious information out of this section. It was very misleading to the reader and basicaly read like an excercise in apologetics. Editors wishing to contribute to this section need to bear Undue Weight in mind as well as the WP:V guidelines, Exceptional claims require exceptional sources. Jefffire 09:18, 23 June 2006 (UTC)

Yeah, and you removed them. Revert them back please. - RoyBoy ⁸⁰⁰ 21:26, 23 June 2006 (UTC)

To be more precise (as the references remained), how does his experimental results require "exceptional sources" in order to be on Wikipedia? How is a popsci reference insufficient according to WP:V. Specify. Also, is not his peer-reviewed findings more than adequate? Or are you concerned about the lack of confirmation on DNA? - RoyBoy ⁸⁰⁰ 01:54, 24 June 2006 (UTC)

To be more precise, we are make quite exceptional claims based on nothing more than one blokes slightly dubious interpration of a phenomenon. As I'm sure your aware, one article does not form a scientific theory. These are not being taken seriously by other scientists, and the guy in question is viewed as something of a kook as a result of this. We are giving him undue weight. Jefffire 11:55, 24 June 2006 (UTC)

I believe your interpretation is dubious; and unnecessarily skeptical. For example your version of the paragraph made it sound like the latest research was off the cuff stuff done in 2001, and that scientists have widely dismissed it directly. That isn't the timeline of events (at least with the references given). ET and even meteor notions were dismissed out of hand (with no compelling evidence for the alternatives presented), and now years later after some analysis, he has published, with some interesting results. If you have "kook" references, or widespread skepticism of the recent paper, please do add it. I appreciate you're observing scientific caution, but find some relevant current sources for you're skepticism. It isn't wrong to expand upon current events, then as meaningful responses/consensus, criticism mount we can update as necessary. Being on the edge of scientific knowledge can easily earn one the "kook" label from the conservative elements. I've seen it for numerous subjects, everything from early prion research to viruses causing some cancers. Turned out they were essentially right. N'est pas? (now, when I donate blood, I have to state if I was in Britain or France during the years they allowed tainted meat in the food supply) You are giving doubters undue weight; although I acknowledge that's how science works... I want to see meat in those doubts. - RoyBoy ⁸⁰⁰ 02:46, 25 June 2006 (UTC)

you guys, please do not substract information from this passege as some did by trimming it in half. if wording has not been appropiate it could be revised, Not Removed. I have reinsrted the main claims for the allien origin of these self reproducing cells. thanks. Procrastinating@^talk2me 10:16, 25 June 2006 (UTC)

• Firstly, you cannot call them microbes, as that has not been established.
• Secondly, you cannot say that they reproduce, only that they are claimed to reproduce by Godfrey.
• Thirdly, if this is as groundbreaking as it is being made out to be, why isn't it major news, with scientist clamouring to steal Godfrey's work?

Please see WP:NPOV#Pseudoscience. Exceptional claims require exceptional sources. Jefffire 20:05, 25 June 2006 (UTC)

On an additional note, all "information" which does not meet Wikipedia's standards of Verifiablility, Reliabilty, Neutality will be, and should be "subtracted". Jefffire 20:31, 25 June 2006 (UTC)

I entirely agree with those points (with the exception of the news point). What I would say is its potentially groundbreaking, and as such until the results are confirmed and additional evidence is in, isotopes and/or DNA, it is preliminary stuff. Also apparently the paper asserts the possibility of a meteor being a source of the red rain, it (hearing this second hand) does not assert an ET life connection itself.

Furthermore, being labeled a "kook" and doing outside mainstream stuff does tend to make major media organizations standoffish; and no scientist wants to be brazen, go to the news networks and then be found to be dead wrong. Things can change rapidly as they are confirmed or discomfirmed, and as such I'd reiterate we have what is the current situation, our Wiki can and will keep pace. - RoyBoy ⁸⁰⁰ 20:56, 25 June 2006 (UTC)

Why was the isotopes and DNA mention removed? Please stop repeating that phrase, it is aggravating how you imploy it inappropriately to justify your edits. Isotopes and DNA are not exceptional claims; they are statements of fact. It is a fact a DNA test came up positive, it is a fact (i think) isotope ratios are key to establishing ET origin. - RoyBoy ⁸⁰⁰ 21:06, 25 June 2006 (UTC)

Cheifly, because it is non-notable, and misleading to the reader. Of especial concern was the highlight that one test showed signs, which was in complete violation of undue weight when there was no mention of the others. Lets wait for the results before getting over excited on this, shall we? Jefffire 21:12, 25 June 2006 (UTC)

I don't understand, especially regarding policy... how does any of this have to do with pseudoscience? And how can a verifiable factoid violate undue weight? No mention of what others? If you mean the other DNA tests, that is inferred from the text saying "one" preliminary test came up positive. - RoyBoy ⁸⁰⁰ 05:24, 26 June 2006 (UTC)

In this case it is not what is mentioned, but what is not mentioned. How many of the DNA tests came up negative? What kind of test was it that can up positive? Was it repeated? The phrasing of the section (such as the reprehensible itilication of the word soon) implies that it is considered important, which it is not. That is why I removed some of the text. Jefffire 13:51, 26 June 2006 (UTC)

That would be decent reason to tweak it (adding caveats such as "only" one test), "preliminary" was in there to give it appropriate weight. You removed it for reasons all your own, undue weight? That doesn't wash. - RoyBoy ⁸⁰⁰ 22:00, 26 June 2006 (UTC)

That wording is still deeply misleading to the reader. I can get a preliminary DNA test to come up negative from a sterile brick, it implies nothing, so why mention it? Undue weight is part of Wikipedia's official policies, not my own. Jefffire 13:17, 27 June 2006 (UTC)

Uh, thanks for the unnecessary primer on Wikipolicy... you can continue to Wikilawyer an admin, or you can speak to me as if I actually have a valid perspective and an understanding of Wikipolicy and culture. The application of policy is always (y)our own unless its spelled out explicitly. Mentioning negative results are entirely relevant to provide appropriate context (weight) to a positive result; which should absolutely be mentioned. Your references to policy have no bearing on the fact it is your POV it is too soon to mention; and/or this line of inquiry is somehow related to pseudoscience. Adding "unconfirmed" to the text resolves such concerns. - RoyBoy ⁸⁰⁰ 15:00, 27 June 2006 (UTC)

My point is that the wording is deeply misleading to the reader. An scientifically unrespected interpratation of the phenomenon is being given an excessive weight and treated as if it were consider a valid line of enquirery amonst the scientific community. The wording as I found it was amonst some of the most atrocious I have found on Wikipedia (such as the italicising of the word soon) so I can be forgiven for assuming that anyone argueing my changes was unfamilure with some Wikipedia policies. In this matter WP:NPOV#Undue_weight is the most applicable. The "life" interpratation is clearly the minor view point, and should be presented as such. Jefffire 15:07, 27 June 2006 (UTC)

LOL, I agree its the minority view; apart from that I consider the rest rubbish and/or not on point. Science (and Wikipedia for that matter) doesn't just examine mainstream ideas, they thrive on new ideas and changes in paradigms. This could be one, or not. Mentioning the positive/interesting results in NPOV language (like removing italics from soon), and what will be happening soon is consistent with Wikipolicy and Wikipedia's strength of remaining current. Adding those things does not remove the line which clarifies the skepticism of the scientific community. Also, nothing is preventing you from adding current caveats and criticism to this paper/results to give it appropriate weight. But for the most part, I think you'll find they (professionals) will hold off until the results are (dis)confirmed. Does that necessitate we wait as well? No, as the results are verifiable and notable; weight is a balancing act, not an exorcism. :"D And when you refer to a policy, please read it thoroughly and remember the context:

"None of this is to say that tiny-minority views cannot receive as much attention as we can give them on pages specifically devoted to them."

Being this is the Panspermia article, this allows for a detailed description, even more detailed than the summary I initially provided. - RoyBoy ⁸⁰⁰ 04:53, 28 June 2006 (UTC)

Hopfully this can be cleared out in the next few weeks or so. either this is a fucking HUGE sceintific breakthrough, or it'd be quiet down by relgious authorities, or turn out to be a rare case of experimental selection bias. YET, the "current" tag and the "claims" wording is sufficiently NPOV based. please do not remove info, as a lot of people are trying to get some better than pop info on this in Wikipedia.Procrastinating@^talk2me 23:03, 27 June 2006 (UTC)

Well, it takes me about an afternoon to test for DNA, and about as long again to examine it in detail, and during that time I could have checked the isotope composition. If these particles are still being tested, they are certainly taking their sweet time about it. I present hypothesis 1: They have already been tested, there have been no positive result (apart from the afore mentioned single preliminary test), and the entire thing has been forgotten by the media. I've taken out the current events tag, since I see no evidence that this is ongoing and appears to be dead in the water. Jefffire 08:40, 28 June 2006 (UTC)

Thanks for finally clarifying your position. As to current event, well I would consider it current because he is waiting for confirmation from the other guy. But no biggie. - RoyBoy ⁸⁰⁰ 01:29, 29 June 2006 (UTC)

[edit] Horizon

UK readers may be interested to know that tonight's Horizon programme at 9pm is on Panspermia and Dr Louis's red rain in particular. Mind you, Horizon isn't what it used to be. (BBC news) -- Solipsist 19:14, 14 November 2006 (UTC)

What I find surprising about the Louis/Wickramasinghe story is that no one, at least as far as I can discern after much scouring, has done gas chromatography mass spectrometry on the raindust. Not only would this provide a fairly good indication of what the stuff actually is but it's also one of the preferred methods for experiments to detect life in space. Other than an assumption of a value of 1.5 (Louis's first paper on arXiv) there isn't even any measure of the raindust's specific gravity. That the story has run as long as it has suggests to me that there must be severe failings in the western mindset: we seem to worship science yet fail to ask obvious questions.

It's worth noting that the previous Horizon programme was about pandemics, H5N1 in particular. Wickramasinghe and Wainwright had suggested in 2003 in a letter to the Lancet that SARS was not a mutation of a coronavirus but was caused by spores from space, and Wickramasinghe has a paper about H5N1 on one of his web pages. Davy p 04:58, 17 November 2006 (UTC)

[edit] Thoery Comment

Panspermia is a well respected theory among the scientific community, it certainly seems if a human being were going to try to logically address the origins of life before documented life on Earth, this would be the most logical perspective. I personally have read many worthy hypothesis pertaining to the question of the origin of carbon based life, so far this is the best and most logical theory i have ever heard. Direct Panspermia would be almost interpretting the bible into a logical modern perspective. Anyone who doesnt agree, needs to review there perception of so called "reality". Even though im merly summarizing my thoughts pertaining to the matter, i hope not to be vague in the least. If you dont agree apart from misunderstanding, allow me to be more specific later on. —The preceding unsigned comment was added by 71.102.233.159 (talk) 09:32, 20 December 2006 (UTC).

[edit] UFO sightings

I've got a serious problem with the following sentance
Over the past century, thousands of people have reported UFO sightings in countries all over the world, but these reports have never been shown to be genuine.
from this section.

It seems totally out of left field, and unnecessary. It's as if someone was purposefully trying to put a dig in against Ufology. For one thing, it's not even true. Project Blue Book most famously could not "explain" 701 out of 12,618 UFO reports, or 6%. This needs to be stricken or modified to be acceptable.

At the very least, the way it is phrased currently is misleading. Yes, to my knowledge, no sighting has been and continues to be definitively held as an extraterrestrial craft. But not every signle reported sighting has had this possibility ruled out either. The fact is that we don't know, and I think this sentance makes a person feel like we do.
--DragonGuyver 20:08, 8 March 2007 (UTC)

I agree that the sentence could be changed to make a point that is more clearly related to the topic of the page. If we had solid evidence for spacecraft visiting Earth from other planets, then it might become possible to explore the idea that life from another planet could have played a role in the development of life on Earth. It might be worth finding a direct quote from a published source that explores the relationship of UFOlogy to panspermia. I'm bothered by statements in the article such as, "Fossilized stromatolites or bacterial aggregates, the oldest of which are dated at 3.5 billion years old, suggest that photosynthesis might be exogenic." I'd like to see a published source that explains this claim. --JWSchmidt 03:14, 9 March 2007 (UTC)

[edit] Stromatolites image

Could someone edit the Stromatolites image to add some sort of scale? It is very difficult to tell what exactly you are looking at, especially for those of us who are not geologists. Robogymnast 19:11, 11 April 2007 (UTC)

[edit] Change to introduction

I propose to change this

"Panspermia is a proven process (based on the principles of Biology, Microbiology, Physics, Chemistry, Astronomy, and assumption that life existed already in the universe) that explains how all life in the universe and/or solar system comes from a 'seed' of life."

to this

"Panspermia is a process (based on the principles of Biology, Microbiology, Physics, Chemistry, Astronomy, and the assumption that life existed already in the universe) that purports to explain how all life in the universe and/or solar system comes from a 'seed' of life."

to reflect the views of mainstrean science more accurately. Any comments? Xxanthippe 06:30, 26 July 2007 (UTC)

Regardless of mainstream opinion, it is a theory and should be stated as such. Therefore the second version is better. --Rocksanddirt 16:05, 27 July 2007 (UTC)

it is clearly a fringe theory, and the intro needs to make this clear from the beginning. dab (𒁳) 12:49, 31 July 2007 (UTC)

I reverted the article to the july 18 version. Neither version above is an accurate description of panspermia. It's not a "process" for example, and the laundry list of sciences is argumentative and adds nothing useful and saying all life came from a seed of life explains nothing.--agr 18:33, 31 July 2007 (UTC)

Given the lack of solid empirical evidence and the lack of falsifiability, panspermia is indeed a hypothesis rather than a theory. The July 18 intro looks appropriate to me. Davy p 22:37, 31 July 2007 (UTC)

I don't have a problem with "hypothesis," but panspermia in the strong sense is quite falsifiable. It appears Mars was wet in the past and failure to detect fossil or active life on Mars, once it's been well explored, would refute the notion that life is ubiquitous in the universe infecting any habitable planet. There are also potentially habitable places in outer planet moons that may have water oceans. Failure to find life there would be another negative. Also we may get better at measuring the spectra of exo-solar system planets. Failure to detect signals of life, such as oxygen atmospheres, would again refute strong panspermia. Exogenesis is another matter. Either life originated entirely on Earth, or it developed, at least in part, somewhere else. This is a question of history. I don't see any strong reason to presume one version over the other. Exogenesis require an additional transfer step, but allows much more time for life to form--a factor of five at least and maybe 30. --agr 23:01, 3 August 2007 (UTC)

[edit] Panspermia is not paranormal

That wikipedia places this article under the category of "paranormal" is ridiculous. The Panspermia Hypothesis is taught in my college-level evolutionary biology class as a perfectly viable alternative to the Miller-Urey experiment. Discoveries like the Murchison meteorite have proven that the Panspermia hypothesis is perfectly testable and perfectly falsifiable. This is a scientific theory that deserves rigorous evaluation. It should not be shunted into the demeaning label that I would reserve for only such garbage as homeopathy, iridology, and dousing. ChrisRay6000 04:52, 5 November 2007 (UTC)

The problem is that much of what is published as 'research' into 'panspermia' is at best pseudoscience. And though some suggestions in astrobiology are falsifiable, much of it isn't. The difference needs to be clear to a casual reader. Science isn't the same as Star Trek. Davy p 11:17, 5 November 2007 (UTC)

Perhaps it would be useful, then, if the Panspermia Hypothesis were differentiated from something like, say, Intelligent Design or Raelianism. There has been a lot of bullshit generated in the study of medicine, but that does not make medicine paranormal. ChrisRay6000 19:11, 5 November 2007 (UTC)

Scientific hypothesis, not theory. Unfortunately, the new-age followers turned the term into a joke.--Svetovid (talk) 20:15, 18 January 2008 (UTC)

[edit] etymology of the word "panspermia"?

What is the etymology of the word "panspermia" and could it be briefly mentioned in the article, please? --Irrevenant [ talk ] 10:36, 6 January 2008 (UTC)

Pan (παν), meaning all + sperm from sperma (σπέρμα), meaning seed + -ia, a noun-forming suffix meaning 'of' or 'belonging to'. Eldereft (talk) 15:53, 6 January 2008 (UTC)

[edit] Bacteria from high in the atmosphere

The Indian team discovering bacteria from high in the atmosphere is mentioned twice, in two separate bullets. Dbutler1986 (talk) 14:33, 3 February 2008 (UTC)

Good point, I have combined them. Eldereft ~(s)talk~ 23:37, 3 February 2008 (UTC)

[edit] These scientific explanations only bring more questions... not answers

If this life seed comes from some other planet... Well how did life started on this other planet? More life seeds? —Preceding unsigned comment added by 70.81.90.169 (talk) 14:19, 9 February 2008 (UTC)

Think of it like an fire investigation in a burnt down house. One possible hypothesis is that a burning ember could have blown in from a fire in a neighboring house fire. It is little more than wild speculation unless you happen to find another burnt down house in the neighborhood, but it would become an excellent and powerful explanation if you happen to find there are hundred burnt down houses in the neighborhood, all the result of "panspermia" flaming embers blowing from house to house.

Yes, that does leave unanswered the question whether the original fire was caused by lightning or bad wiring or arson. However that in no way alters the (potential) truth of the explanation for the fire in this house, and does not diminish the (potential) achievement of solving this house fire. The "fire marshal" can close the case on this house, and move on to a new investigation involving different evidence elsewhere. It would explain why (hypothetically) this house fire started in the middle of the roof with no lightning scorch marks and no bad writing and no evidence of arson and none of the other typical evidence one might expect for a cause. However at some other scene we might indeed find clear and fully explanatory evidence of a lightning strike or defective wiring or an arson scene complete with fingerprints of the arsonist.

Science doesn't need to answer everything at once in order to be right. Science solves things one piece at a time. Every answer is followed by new questions. In 1900 all evidence proved chemistry was true, even when we had no good explanation for the origin of elements (which we later did solve as originating by nuclear fusion inside stars). In 2000 all evidence proves evolution is true, even if when we do not have any solid answer for the origin of life. Panspermia is purely hypothetical, but failing to answer the-origin-of-life has no bearing on whether is it true or not. Alsee (talk) 02:48, 21 April 2008 (UTC)

[edit] Not Exactly

But, quite plausible. —Preceding unsigned comment added by Rdailey1 (talk • contribs) 02:40, 1 April 2008 (UTC)

[edit] Evidence of extraterrestrial life

The introduction to this section has to go. There's no room in a responsible article for a comment like "The majority view in the scientific community seems to be an acceptance that the existence of intelligent life elsewhere in the Universe is highly probable...". That's just not backed up, and the argument given, of potential sites is hugely simplistic, and may consititute original research. Also, there's been no response to the fact tag for six months. I'm feeling uninspired in terms of re-writing it however. Anybody care to? Cmsg —Preceding unsigned comment added by Cmsg (talk • contribs) 13:46, 24 April 2008 (UTC)

I have re-editied and re-labeled the section entirely: "Extraterrestrial intelligence?" which suits it's speculative nature. It is not perfect but much much better than it was. Reason being the Drake equation which is the only scientific way of looking at this: evidence! astrobiology, Fermi paradox (scientific too), Rare Earth... wikified links etc. UFO stuff is topical and needs explanantion not ridicule. Section is now a mainstream explanation of extraterrestrial intelligence (as we unfortunately dont know it!). The UFO phenomena needs explanation in the scientific community (psychology: meaning dream states and levels of conciousness between sleep and waking... radical physical theory (wormholes) or multiverse (wormholes) (maybe another 1,000, 10,000, 1,000,000 years if homo sapiens survives that long on this planet (our only one and the only one!) for that long (global warming, population growth, environmental damage, unsustainability... ) personally I wish that there were some benevolent little green dictators that far ahead of us to come and run the planet for us! ahum :-( 122.148.173.37 (talk) 21:24, 17 May 2008 (UTC)

In retrospect: I think the whole section should probably go as it is probably not that relevant to panspermia and is covered in some of the other article I have mentioned. The nly rteson it was there in its origginal form i think wa the satisfy the UFO-ologists and Eric Von Danekinists. 122.148.173.37 (talk) 07:30, 18 May 2008 (UTC)

My conlusion is this entire article is very poorly written. 122.148.173.37 (talk) 07:35, 18 May 2008 (UTC)

Changed the section title back and im outa here... 122.148.173.37 (talk) 07:40, 18 May 2008 (UTC)

This section is quite complete and satisfying now if it is to be contained in the article at all except for a possible change to the title like "Evidence of intelligent extraterrestrial life" but that mignth not quite fit into the earlier and later sections either so I will leave this for someone else to explore and fix please!? Regards, 122.148.173.37 (talk) 14:35, 11 June 2008 (UTC)

[edit] Pop culture

I have removed the following section. Panspermia in abstracto is a far too common theme in science fiction, so I think that unless a specific reliable source makes an explicit connection between a work and the term "panspermia", that the popular culture reference should not be included in the article. The items which do appear to have sources appear to be promotional, and so not really suitable for inclusion in the article anyway. silly rabbit (talk) 16:46, 15 May 2008 (UTC)

==References in popular culture==

• Panspermia is in the X-Files episode "Bio-Genesis".

• Directed panspermia is the theme of the Star Trek: The Next Generation episode "The Chase."

• In the opening sequence of Spore, a protein laden comet crashes to the player's planet, triggering life and the start of the cellular phase of game play.

• The opening of the animated music video for Pearl Jam's "Do the Evolution" features a comet crashing into a barren Earth, followed by scenes depicting simple organisms gradually evolving into more complex lifeforms.

• Fiction writer Dan Brown also includes panspermia in the novel Deception Point.

• Panspermia is the main theme of the movie Mission to Mars.

• The novel The Gripping Hand by Larry Niven and Jerry Pournelle mentions that panspermia is a commonly accepted theory in that Universe. Niven also extensively writes about both directed and non-directed panspermia in his Known-Space novels.

• The film Panspermia by computer graphics artist Karl Sims features a world of complex and diverse species created by using "artificial evolution".^[1] It has become one of the most influential works in the fields of both computer graphics and artificial life.^[2] It was edited into the "Seeds of Life" segment of the computer graphics compilations Beyond the Mind's Eye and Virtual Nature.

• The film Evolution contains alien creatures who evolved from cells of life brought down from a meteorite.

• The musical group Panspermians^[3] derives its name from the theory.

• The continous story-line on most albums by the Dutch metal band Ayreon is the alien entity Forever of the Stars who planted its seeds on Earth. The most notable narrative of this is the track Ride the Comet on the latest studio album 01011001.

=== Science fiction ===

The theory of panspermia has been explored in a number of works of science fiction, notably Jack Finney's The Body Snatchers (four times made into a film) and the Dragonriders of Pern books of Anne McCaffrey. In John Wyndham's book, The Day of the Triffids (also made into a film), the first person narrator, writing in historical mode, takes care to reject the theory of panspermia in favour of the conclusion that the eponymous carnivorous plants are a product of Soviet biotechnology. The book and film of The Andromeda Strain examines the consequences of a pathogenic extraterrestrial organism arriving on Earth.

In contrast, Stephen Baxter's Titan suggests the possibility of geocentric panspermia: the astronaut's final dying act is to release bacteria into a Titanian lake. The theme is continued as the resultant beetle-like civilisation purposefully colonise new star systems.

Some works of science fiction advance a derivative of the theory as a rationalization for the improbable tendency of fictional extraterrestrials to be strongly humanoid in form as well as living on earth-compatible worlds (see Class M planet) and having similar levels of technology. In a Star Trek: The Next Generation episode ("The Chase"), the humanoid aliens, which include the humans themselves, are results of the genetic codes spread through the Universe by the Ancient humanoids and were placed by the Ancient humanoids themselves.

[edit] References