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New Theory Explains Periodic Mass Extinctions
i_like_spam writes "The theory that the dinosaurs were wiped out by an asteroid impact, the K-T extinction, is well known and supported by fossil and geological evidence. Asteroid impact theory does not apply to the other fluctuations in biodiversity, however, which follow an approximate 62 million-year cycle. As reported in Science, a new theory seems to explain periodic mass extinctions. The new theory found that oscillations in the Sun relative to the plane of the Milky Way correlate with changes in biodiversity on Earth. The researchers suggest that an increase in the exposure of Earth to extragalactic cosmic rays causes mass extinctions. The original paper describing the findings is available online."
Only 7 million years from now, for all you long range planners. Better stock up on beans, bottled water and relocate your house 1 kilometer underground.
It's a perfectly reasonable hypothesis, though it'll be a while before we can test it. It's always a little weird though, to think of extra-solar events as relevant on a "local" scale. I mean, in the same way that Earth is endangered by rogue meteorites and asteroids, the whole solar system is vulnerable to a rogue star or brown dwarf. Anyone ever read Jack McDevitt? He's obsessed with that sort of disaster (pun intended).
Hard to get your mind around it...The odds are so long...
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
lead based sun block?
Will my tinfoil hat protect me ?
Shakespeare poems - infinite monkeys with infinite time.Computer tech support - a few trained ones working from 9 to 5.
Well, that would explain the world-wide black stratum in the planet's rocks that make the K-T event so readily identifiable.
Or not. Does this theory merely half-explain what we already know or does it make other stuff that we couldn't explain come out right, too? Sounds like the former...
Greg Egan did a book on this very topic, except it was a dual neutron star that collided with each other.
Egan, near the end of the book, explained that energy was being transfered into extra-dimensional energy, and not sealing behind an event horizon as it normally should.
In the book, the binary was a hundred light-years away. It caused mass extinction of the flesher human race, however the digitized humans were safe.
The book was called Diaspora.
I have just finished reading "Second Genesis" by Donald Moffitt from 1986, that has a very similar explanation for mass extinctions!
How about 'new hypothesis may explain...'
A couple of 30-somethings embark on the ultimate roadtrip
Everyone knows the extinctions were perfectly explained using the Theory of Intelligent Smiting.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Check out Figure 4 at the end of the linked paper. It shows that the periods of highest diversity coincide with the periods where the cosmic ray flux is lowest. Really amazing correlation if you ask me.
Here's an idea: why not RTFA? It's not long.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
but which way does the causality if any run? :P
;)p
just like pirates cause global cooling...
http://www.seanbonner.com/blog/archives/001857.ph
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
It's not even a new slashdot article.
i took a bitchslapping for natalie portman
So the coolaid people actually had it right, they were just off by a few years.
The researchers suggest that an increase in the exposure of Earth to extragalactic cosmic rays causes mass extinctions.
Or maybe, the increased radiation merely causes some periods of increased mutations... extinctions follow as species are outcompeted for resources.
But NOVA Science Now told me it was global warming :(
You must be new here.
Can we please oh please oh please call them death rays?
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
I believe it was 28-30 million light years, and then its axis for gamma rays would have to be pointing directly at where the earth would cross the relatively brief beam. IOW, you're more likely to get directly hit by a killer asteroid.
The cesspool just got a check and balance.
It's a perfectly reasonable hypothesis if one accepts the premise that mass extinctions have an approximately 62 million year period. From Wikipedia, the last 6 extinction events happened 65 million years ago, 200 million years ago, 251 million years ago, 360 million years ago, 444 million years ago, and 488 million years ago. The time between extinctions being 135 million years, 51 million years, 109 million years, 84 million years, and 44 million years. I'm having a hard time wrapping even an approximate 62 million year period into those.
Ben Hocking
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Why would it wipe out only 10% of the SPECIES?
How/Why did the other 90% survive?
Muons can punch through rock. They'd be hitting every living thing on Earth. Yet 90% of the species seem to survive. While 10% die off.
Post again in 7 million years...
Shakespeare poems - infinite monkeys with infinite time.Computer tech support - a few trained ones working from 9 to 5.
What else is it going to be, genius? Theory is the last step. You think it's going to grow up and be the "Truth of Evolution" or something?
A truth is a fact, and facts are trivial. You need a Theory to link all those facts together into something useful, something testable, with predictive power.
Just a theory. Jesus. Is it troll day or something?
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Humanity's chances of avoiding self-destruction or regression to a simian mean within the next 7 million years approximate zero, or worse (Cantor sets).
technical writing / development
Specifically, you're confusing now with 7 million years in the future. I understand, it's pretty easy for some people to get them confused.
Ben Hocking
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Maybe there's an impact every 62 million years after all. I hereby posit that Earth is one of spheres in a giant Newton's Cradle
I for one welcome our new cosmic ray-based overlords! (I just felt like I hadn't seen that lately. :'( Mod me as you wish. But, be gentle.)
This is hardly a new idea. It was discussed in my galactic physics class in 1995, and I don't think it was a new idea even then.
..it is just that whenever I hear about a spectacular new hypothesis about anything that relates to: evolution, climate, weather, nuclear power, solar power, cellphone's or HIV, I almost immediately start grinding my teeth because I just know it will be jumped upon by some media outlet and spun into political propaganda. With this particular one I'm expecting at the very least a few GW sceptics and ID promoters, but with some (bad)luck maybe we can get some references to free energy devices as well... Heck, GW and ID has already been mentioned in the comments...
you say: "A truth is a fact,"
Indiana Jones says, "Archaeology is the search for fact... not truth. If it's truth you're looking for, Dr. Tyree's philosophy class is right down the hall."
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
Almost all of the diversity minima precede the cosmic ray maxima, and all of the declines (from diversity maxima) precede the cosmic ray maxima. I think you're on to something there... ;)
Ben Hocking
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Radiation doesn't kill things off that well. Look at Chernobyl or the Savannah river plant...Both shut down, both radioactive, both experiencing a resurgence of pretty healthy wildlife across the board.
Lot of the things we assumed about radiation back in the day (e.g. mutants and Godzilla) have turned out to not really happen so much. DNA isn't as fragile as we assumed, and while the extra rads may kill you quicker (only live to 60 instead of 80), it's not quick enough to keep you from reproducing.
We're not talking some kind of galactic nuke here...It's just a significant upswing in radiation. Hell, the fact that we've had these historically is maybe why the ecosystem tolerates increases in radiation so well.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
The extinction events are too abrupt to be explained this way, and the "approximate 62 million-year cycle" only looks like a cycle if you squint really hard.
Although radiation sources in other galaxies are locally very powerful, I believe that these sources are too far away to have such a drastic effect on earth life. The closest galaxy is 2.3 million light years away. You do the math.
I'm sure increased cosmic ray exposure would increase genetic mutation and increase biodiversity though. :)
Some of our oldest probes are just now leaving the heliopause (which tends to move around a bit), and they were launched 30 or more years ago. Also, I think it might be harder to use a multiple-planet gravity assist to help with speed, although I could be wrong about that.
Ben Hocking
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That's the problem. This theory says that the radiation killed off 10% of the species on Earth.
That IS killing things off pretty well. That's "decimating" the number of species on Earth.
And we're not talking about a specific threat to specific ecosystems. The oceans didn't evaporate nor did they freeze. The radiation covered the Earth and only killed off 10% of the species. Multiple times.
That does not make sense. Either a LOT more die or it only takes out the weaker individuals in ALL species.
This is all lies, my president told me the dinosaurs were killed by cavemen.
Have you been touched?
The scale is simply too big to allow meaningful data return in less than many millennia. The hypothesis is talking about exposure to the galactic bow shock wave created as the galaxy moves through the intergalactic medium. The probe would need to move significantly "up" relative to the galactic equator to measure the difference in radiation.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
I recall reading one guys work on galactic dynamics where he suggested that our solar system "orbits" or oscillates (planar) through one of the arms (dense areas - we're not a pinwheel) of the galaxy. He suggested that as we pass through the middle, we're more likely to be hit by other objects. This was his explanation for the extinctions. Now we see that someone has concluded such an oscillation is really happening, however they suggest the a different phase relationship. The guy I was talking about would have the extinctions happen at the time of lowest cosmic ray flux. I guess he got the oscillation part right and the cause of the extinctions wrong. Too bad I can remember where I read that...
Now, subject 100,000 species to a high dosage, over generations.
Would you expect to see no problems for 90% of the species? While 10% die off?
I wouldn't. Enough radiation to kill an entire SPECIES would, logically, have an effect on other species that share the same ecosystem.
But we don't see that in the fossil record.
The K-T boundary is not the only one with some pretty good geological/impact evidence to go along with it.
I recall reading about two separate other ones, T-P in particular comes to mind. Some just need the "gun" (a crater or volcano).
So, you sort of not only need to come up with a new theory, but come up with a new theory that better fits the time lines and the details of what we think happened better than the existing one. For T-P, there are volcanic deposits that could have been involved around that time. (And an impact in Antarctica that hasn't had it's date narrowed down well enough to be a contender without a big "?" after it.
I have long thought that asteroid impact was responsible for the K-T Extinction Event, but as to other extinctions, I still don't really see them as cyclic with any real constant period. Add to that the fact that the largest such event ever, the Permian-Triassic Extinction Event appears to have been caused by massive volcanic activity in the Siberian Traps of Asia (itself caused by mantle plumes). What you are left with is an assortment of lesser events which, as measured by the marine biodiversity historically, don't really conform to much of a cyclic pattern at all.
Pure coincidence, similar to the fact that the spacing of the planets appears to roughly follow a simple polynomial formula - after ignoring the single glaring exception.
OK, I've only read the summary (I have a lecture to give half an hour from now to prepare for) but I can see some objections:
* My boss (David Penny, Massey University) argues that the mammals and birds were already outcompeting the dinosaurs at the end of the cretaceous, so the asteroid was at best a coup-de-grace for them.
* The "periodic extinctions" idea has been around for decades, including the possible link to oscillations through the galactic plane.
* Mass extinctions are sudden. The increase in extragalactic cosmic rays exposure would be slow, over millions of years.
* The extragalactic cosmic ray exposure changes should be highly regular. The extinctions are irregular.
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Where, the "hypothesis" is the question "what if X?" and the support is some guy goes out and digs it up, graphs it out, discovers a new branch of math to show it, etc. and then publishes some papers about it saying so.
The fact you ask that dumb question without even understanding the basics of science as (supposedly) taught in 4th grade, makes you a troll.
Now go back to Digg or something.
Using on on board delta-V would result in a much slower probe.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Ben Hocking
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The first time, yes.
After that, every branch left should have whatever enabled them to survive that first time. All the species 65 million years later are descendants of the species that survived the first radiation wave.
- 251-200 = 51 myr - doesn't fit nicely with 62 myr cycle
- 360-251 = 111 myr - "
- 360-200 = 160 myr - "
- 444-360 = 84 myr - "
- 444-251 = 193 myr - OK, this one isn't too bad (cf. 186 myr = 62 myr x 3)
- 444-200 = 244 myr - Pretty good (cf. 248), but only one of the 2 (200,251) could be on-cycle
- 488-444 = 44 myr - doesn't fit nicely with 62 myr cycle
- 488-360 = 128 myr - Not too bad, but out of cycle with 444, so...
- 488-251 = 237 myr - doesn't fit nicely with 62 myr cycle
- 488-200 = 288 myr - "
So, either the 488 and 360 myr ago events were on cycle, the 444 myr and 251 myr events were on cycle, or the 444 and 200 myr events were on cycle. 2 of the other 4 were were off-cycle. Keep in mind that to have only one of them "on-cycle" is meaningless, so this seems like a bigger miss than a hit. Granted, this is all amateur analysis.Ben Hocking
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No, dinosaurs died because they were drowning in amber.
The title of the summary is totally wrong. This has nothing to do with mass extinctions. Its looking at fossil Species and Family counts vs time correlated with Solar motion. The 62 MY cycle barely touches the Mass extinction events.
Better summary title - "Life's Diversity changes with Solar Galactic Orbit". Or something like that.
Mars is no better. Our solar system is just a slightly bigger basket. In this case a hand-basket...
Ben Hocking
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Evolution tends towards the more complex. Not simplification. Once you get a DNA sequence, it's pretty much there forever.
That's how we're able to trace genetic lines in evolution.
There's no more energy required for a species with 23 pairs of chromosomes to breed than a species with only 22.
see Cosmic Killer in http://www.cbc.ca/quirks/archives/06-07/may05.html
Asimov already stated, in the prequels of the foundation, sequels to I robot (written much much latter than foundation or I robot), the earth is special because of internal radiation (both earth and solar system radiation, with emphasis on earth radiation). Is the cause of biological diversity and there are no alien civilizations. And his novels have more science than most evolution,ID,GW,ET theories these days.
"to study the ... transition region of the heliosphere"
I was surprised myself to discover that. And, as already pointed out, visiting the other planets made it faster, not slower.Ben Hocking
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Slow day for news??!! This was discussed in the book "Comet" by Carl Sagan in 1989 for heaven's sake!!
My web domain.
As previously alluded to, it could be that the survival mechanism is to be small and reproduce quickly. There's selection pressure on some species to be large. These species would have a harder time adapting quickly due to a slower reproductive cycle (fewer generations per year/century).
(Sure, that's encoded in the genes, but it's not exactly a simple DNA sequence.)
Ben Hocking
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the mass extinsion was caused by the attempt to convert from ipv4 to ipv6. caveat emptor!
Now get off my lawn!
Someone hates these cans.
And you didn't even specifically mention Mars in your original post. I was just pointing out that in this case we would need to talk about leaving the solar system. I suspect that if we get a sustainable colony on Mars by 2107 (500 years after Jamestown), then perhaps we could have an extra-solar system colony by 2607 (based on nothing but extremely wild extrapolation).
Ben Hocking
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Why does this remind me of the stuff that Aztec scientists beleived
"sudo rm -rf your-face"
But we're already in possibly the biggest extinction event on record:
We can't blame this one on the Sun's distant future interaction with the Galactic Ecliptic. We've been working for this one pretty hard ourselves already.
--
make install -not war
Exactly the same as the article summary. I don't remember the title, though. Anyone?
If you need text styles to communicate then you don't have a message.
Ben Hocking
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Every 50,000 years or so, the earths polarity changes as the earths mantle currents change, and whilst this changeover is taking place, the van allen belts which protect us from cosmic rays effectively shut down, and huge amounts of cosmic radiation hit the earth. This could cause extinctions, as well as evolution.
The great extinction of close to 300 million years ago was likely to be down to the Siberian basalt lakes, vast lakes of lava which heated up the earth, which in turn released loads of frozen methane from the bottom of the seabed, warming the earth even more.
There is geological evidence for both of these, such as the atlantic ridge pumping out rock which is expanding both east and west as the European and American continents are push away from each other. The rock changes magnetic polarity in strips as it is pushed away, and the timeline of the the change in earths polarity has been extrapolated from this. We also have the strata in greenland which shows a black layer caused by the basalt lakes, dated almost 300 million years ago..
Just some random related ideas which could be responsible for the same sort of thing.
Right. Now it's time to RTFA!
I do not fear computers. I fear the lack of them. Isaac Asimov
I hate every ape I see, From chimpan-A to chimpanzee.
Just, be glad the librarian wasn't about.
What if Tetris was invented by Nazis?
You actually made me do the math to find out it equals 84.6. Which, I'm sure, you already knew. :P
Ben Hocking
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This is just great. Now there are two ways to go extinct.
the researchers determined, the sun reaches the highest point in its orbit relative to the galactic plane, where most Milky Way stars reside.
So each time we pop our head out of our hole, aliens start taking potshots at us.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
It would be
I hate every Ape-I-See
from Chimp-an-A
to Chimp-an-Z
Linux Zealots: Smarter than Mac Zealots, but still zealots.
Cycle:Min Diversity:Max Diversity
1:59 My:74 My
2:115 My:121 My
3:177 My:184 My
4:250 My:273 My
5:298 My:308 My
6:372 My:400 My
7:441 My:454 My
8:497 My:501 My
My calculations:
MinAgeDiff:MaxAgeDiff
56 My:47 My
62 My:63 My
73 My:89 My
48 My:35 Mr
74 My:92 My
69 My:54 My
56 My:47 My
Personally, I'm not impressed by the 62 My period conclusion based on the data they provide. Just how approximate are we talking here?
Ben Hocking
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new MS OS release cycles - perhaps they cause mass extinctions
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
I, for one, would like to commemorate a few periodic mass extinctions:
Dear AU, what has become of you? You may not be extinct, but I can never find you.
Humble Promethium. Your existence was "predicted" long after your demise.
Oh 271 Seaborgium, how did you decay? Let me count the ways. Alpha decay. Spontaneous fission.
272 Roentgenium, we hardly knew you. Half extinct at the tender age of 1.5ms. You're the one we'll truly miss.
https://www.eff.org/https-everywhere
Heres a thought.
The cycles of motion of our sun through the galaxy could cause gravitational perturbations in the orbits of objects in the oort cloud or kuiper belt.
Those peturbations could, in the long run, result in more earth-crossing objects and therefore impacts.
Those impacts could, directly, lead to loss of biodiversity or, indirectly through setting off cataclysmic vulcanism lead to loss of biodiversity.
Therefore, its possible that the cyclic motion of the sun could lead to extinction events which are don't directly intersect with those cycles.
Caution: I am not an astrophysicist but I might play one in a roleplaying game.
In the free world the media isn't government run; the government is media run.
When I was into the cosmology-for-dummies books that were popular in the 80s and 90s (Hawkings, Sagan, etc), I read about this theory. Another one was Nemesis, a dark star or other companion to the Sun that perturbed the Oort cloud (Kuiper belt too?) with the same frequency as the extinction cycle. Every book always said the theory could be disproved with a few years worth of measurements, so I'm guessing that happened years ago.
I swear to God...I swear to God! That is NOT how you treat your human!
your the dumbass for buying without any proof.
As our sun orbits toward the face of the galactic disc it encounters extrasolar objects more often due to the more chaotic motion of masses in that zone. The galactic plane is brightest because the vast majority of masses in it never stray and so their motion is orderly in two dimensions. It's the wandering suns with orbits slightly inclined like ours that are the troublemakers that wander away from the order of the plane and mix it up.
duh.
Help stamp out iliturcy.
no!! it was the big green boogey man in the sky!! because it was HIS will, and HE works in mysterious ways
licet differant, aequabitur
Now, we just need a gorgeous blonde, her cocky younger brother, a ruff-n-tuff pilot and a pissy corporate type who has secret plans for world domination. Oh, and his space station to observe this radiation from. It's shields will protect us. Man, what a GREAT movie concept this would be!!! Ok, ok.. I'll go back to playing Farcry now.
To speak to some mistaken assumptions used as analogy:
This is not a coincidence any more than the spacing of the planets. Those are spaced according to minima in gravitational disturbance from other planets. They 'fell' into these minima after wobbling around in other orbits.
This has nothing to do with the KT event or other impact or volcanic events, Subtract those from the history of extinction events and the 62 million year becomes evident.
That said, the predicted influx of cosmic rays would have two primary results, the first a hypothetical events untestable at the present level of incoming cosmic rays, the other one having two implications.
The first result would be an increase in cloud cover. Cosmic rays were hypothesized to contribute to cloud formation. Measurements have since shown that this is not occurring, or at least not enough to be statistically significantly detectable among the other causes of cloud cover. Lab experiments show it can happen. It remains to be seen how much this would occur given the amount of cosmic rays expected from the galactic bow shock.
The second would be a large increase in changes in DNA. This would cause many mutations, including cancers. Many species would succumb to the changes and die off. The few of such species to survive might be too isolated from each other to mate and produce offspring also resistant. The second implication that among the DNA changes, while most would be harmful, some would produce chancges that would benefit the organism/species, and increase its survivability. This is why mosy species die off, but a few survive. Also, among those that survive, there is an explosion of diversity, possibly due to the increased survivability.
We've got about 12 million dollars to the peak of the effect. We don't know when it would start, or increase enough to start having an effect.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Given the benefit of current technology, including technology developed for the US space program, catching up with the US government is more a question of funding than time. With insufficient funding, it could take much longer than 50 years to catch up; if somehow enough money became available, it could be done much more quickly.
In any case, commercial applications for interstellar probes seem unlikely, so you might never get that wakeup call.
I'm sure I've seen this before, possibly found out about it on /.
/ 03/10/MNGFIBN6PO1.DTL
Here's an article from March 2005
http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005
It's only one of many theories. The wikipedia page that points to the article above discusses them all
http://en.wikipedia.org/wiki/Mass_extinction
These posts express my own personal views, not those of my employer
http://www.google.com/search?hl=en&q=(135+%2B+51+% 2B+109+%2B+84+%2B+44)+%2F+5+%3D+&btnG=Google+Searc h
I didn't have to do the math.. I also no longer need to spell..
every day http://en.wikipedia.org/wiki/Special:Random
'nuff said
Uhhh.... anyone notice its from kansas?........ Last time the state of Kansas made any contribution to science was in 1925 with the Scopes trial. And dont try to argue otherwise, its a universally accepted truththat Kansas' last contribution was 1925. srsly
A conclusion is the place where you got tired of thinking
Hyperspace with Sam Neill had a segment talking about just this.
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It can see you
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OH DO BE QUIET.
I feel fantastic, and I'm still alive.
"God does not play dice [with the universe]."
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
Passing closer to other stars influences the Kuiper belt objects and due to gravitational changes some are distorted from their more or less circular / stationary orbits. Orbits might become more eliptical, which from out Earthly perspecitve seems as pack of comets jetisoned towards the centre of Solar system in short few hundred thousand years period.
Result: every such passage means we get hit once or twice
Well.... is this rat civilization made up of moon rats? That I could see.
This theory is not intended to explain the large, irregular, rapid mass extinctions, but rather smaller, regular, gradual biodiversity changes. And the 62 million year cycle that they're trying to explain has not been known for decades; it was only discovered two years ago.
Why didn't I think of that! ;)
But seriously, as crazy as your idea sounds (to me, at least), it's not as bad as it seems at first blush. Self-replicating machinery capable of using the asteroids to propagate themselves while creating this enormous "machine" could accomplish this. OTOH, they might decide that the solar system could use a little "cleansing".
Ben Hocking
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True, he was the first human to make the trip around the planet, but it was more accidental, and as you say with a long break in between.
Elcano was crew, and captain for a good part of the voyage -- he was actually doing the navigation part of the circumnavigation. Enriquez was just along for the ride (in terms of navigation or sailing duties, at least).
-- Alastair
I read the entire series. We wouldn't really have to assume we'd find uninhabited raw resources at the destination. Presumably we would build probes to answer that question first. Of course, that adds time on to the trip - for the probe to get there and for us to get back the probe's signal. Presumably, we'd launch several probes to many nearby systems to increase our chances. Alternatively, if energy is no object, we can actually travel effectively faster than the speed of light even with current scientific understanding (notwithstanding the part about energy being no object). (By effectively faster, I mean that we could travel to a star 10 light years away in less than 10 years ship time, although more than 10 years will have passed on Earth. As we approach the speed of light, the distance gets contracted, thus allowing us to get there in a shorter amount of ship time)
Ben Hocking
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I just un-did.
Scary thing is, nobody noticed this for two days!
(T>t && O(n)--) == sqrt(666)
A cyclical decrease in biodiversity on planet Earth every 62million years.
A plausible hypothesis. Like any viable hypothesis it needs a thorough testing, which in my opinion is a job better done by professional like the a paleontologist, micro- and molecular-biologists.
If the hypothesis is correct, I think these periodic extinctions should exhibit a more or less a distinct and recognizable pattern. Analogous patterns, concerning the percentage of these periodic extinctions related to the overall extant biodiversity, in genetic variations, (including proportionally high mutations), a recognizable pattern in the geographical transformations and in biosphere, a pattern in distribution of water, spores and the biomass, specific effects that such recurrent CRS may induce in reproductive behaviors of some species (let us say, like plants shedding pollen at unusual times of the year, insects or other species taking the upper hand or an increased sudden evolution of new strains of bacteria or other species with short life-spans) and many more, that I probably can not imagine. Modern technology is to a large extent capable of investigating such matters. If such investigations do reveal a co-relevance, I see no reason why this hypothesis may not reflect a fact, that no doubt due to its inherent implications, coming as it does at a time, when Global Climate is a hot contested topic may at first glance, appear to be less like a routine scientific investigation and more of a propaganda, Not knowing the authors or their history I am at first inclined to be impartial and feel in no way competent to judge its viability, nevertheless hope that a thorough testing by professionals in the biological sciences would follows soon. Moreover I see no contradiction or even any direct relationship here with the confirmed and to large extent well explained facts of our planetary history. In fact the great cataclysmic extinctions induced by irregular accidental cosmic or geological events are not the objects of investigations here.