Unlocking one of the great secrets of Earth's evolution

February 19, 2016
Unlocking one of the great secrets of Earth’s evolution

An international team including scientists at the University of St Andrews has unlocked the secret of one of the great events of Earth's evolution – the Cambrian explosion.

Around 520 million years ago, a wide variety of animals burst onto the evolutionary scene in an event known as the Cambrian explosion. In perhaps as few as 10 million years, marine animals evolved most of the basic body forms that we observe in modern groups.

The event has sparked fierce debate all the way back to Darwin. Some paleontologists see the Cambrian explosion as a real, astonishing episode of unprecedented, fast evolution. Others suggest it is a false artifact of an unreliable fossil record. 

Now work published in the American Journal of Science shows that these competing theories can be unified by the geography of Cambrian Earth, as it underwent a wholesale lurch that clustered most of Earth's continents around the equator.

Co-author Dr Timothy Raub of the Department of Earth and Environmental Sciences at the University of St Andrews said: "In a nutshell both camps were right. The particular locations of Cambrian continents relative to each other was special in a way that supercharged animal speciation while preserving an unusually good record of those early fossils."

The key event, proposed long ago by co-author Joseph Kirschvink from Caltech and Japan's Earth-Life Science Institute (ELSI), was a massive episode of what is known as 'true polar wander'.  Raub, Kirschvink, and lead author Ross Mitchell of Caltech and Yale University are among scientists who have bolstered the evidence for true polar wander and developed predictions of its consequences in recent years.

Earth's continental and oceanic plates are in constant motion relative to one another, but in rare episodes of true polar wander, the entire solid Earth slips about its liquid outer core over the course of five to ten millions years, causing the geographic locations of Earth's plates to shift altogether in the same sense.

The paper suggests that about 520 million years ago a lurch of more than 60 degrees moved most continents from polar to tropical latitudes. For reasons that are still debated, biological diversity reaches a global peak around the equator and tapers off closer to the poles. This early Cambrian rotation therefore would have dramatically increased shallow coastal area in Earth's biodiversity hotspot.

As another consequence of true polar wander, continents moving towards the equator are flooded by hundreds of metres of sea level rise, as they encounter the great bulge of water caused by Earth's daily spin. This flooding would have increased fossil preservation, but it also would have opened up new habitats for rapid diversification, in particular vast continental seaways rife with previously unexplored ecological niches. 

Cambrian true polar wander happened at a time when Earth was already seeded with many of the traits that subsequently radiated throughout the Tree of Life.

‌‌Dr Raub (pictured) said: "A bunch of wonderful ideas have been published emphasising one or another aspect of the Cambrian biosphere as the crucial link in the explosion of animal life. An appealing aspect of our study is that a geographic contingency – the shape and arrangement of the Cambrian continents and the direction of the remarkable true polar wander shift – can support almost all those ideas simultaneously. At the same time, it turns out that preservation of Cambrian fossils really was enhanced over that of other ages.

"This new geographic framework answers a debate going back over a hundred years. It should encourage scientists to review all sorts of old and new hypotheses, which no longer must fit into the evolution or preservation camp exclusively."

Explore further: Gondwana supercontinent underwent massive shift during Cambrian explosion

More information: 'Was the Cambrian explosion both an effect and an artifact of true polar wander?' Ross N. Mitchell, Timothy D. Raub, Samuel C. Silva, Joseph L. Kirschvink is published in the American Journal of Science.

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Mark Thomas
4 / 5 (3) Feb 19, 2016
If Earth experiences "true polar wander" what does that say about the stabilizing effects of the moon?
promile
Feb 19, 2016
This comment has been removed by a moderator.
viko_mx
Feb 19, 2016
This comment has been removed by a moderator.
viko_mx
Feb 19, 2016
This comment has been removed by a moderator.
AstroDwarf
4.4 / 5 (13) Feb 19, 2016
@viko_mx

tinfoil hats available here...

https://www.kicks...headwear
FredJose
1.3 / 5 (16) Feb 19, 2016
As another consequence of true polar wander, continents moving towards the equator are flooded by hundreds of metres of sea level rise, as they encounter the great bulge of water caused by Earth's daily spin. This flooding would have increased fossil preservation, but it also would have opened up new habitats for rapid diversification, in particular vast continental seaways rife with previously unexplored ecological niches.

I dont know just how close this can be to plagiarism but the creationists already have a model of exactly this kind of movement of the earths upper layers during the biblical flood.
I refer you to the work of Dr John Baumgardner in a DVD named ¨Planetary Cataclysm¨ which explains
the effect of the flood on the earth as we know it. Go watch it for yourselves and see who proposed this idea first. Note how it also makes perfect sense of the reversal of the magnetic fields in the space of weeks as recorded in volcanic and other eruptive layers.
TheGhostofOtto1923
4.1 / 5 (14) Feb 19, 2016
evolutionists are masters of paradox
No, a clear example of paradox is an all-powerful and impeccably moral god who could do any number of good and honorable things, but chooses instead to obliterate evidence for the past and replace it with totally convincing and complete contrary evidence.

In other words he lies to you. About everything.

And further, he left it to you believers to explain all this contrary evidence in ways which confirm and not deny his mighty hand.

So why does he make you suffer so?

Geology and archeology both prove that your god is a hapless boor.
http://ncse.com/c...-geology

-I know you won't read it because you're already in enough pain.
TheGhostofOtto1923
4.1 / 5 (13) Feb 19, 2016
Note how it also makes perfect sense
How would you know if it makes perfect sense? The only way you would know if it made perfect sense or not, is if someone told you.

Who told you it made perfect sense?
Phys1
4.4 / 5 (14) Feb 19, 2016
@viko_mx
Long ago I became convinced ...

Who cares? You are just another religious fool.
You have been such a fool since a long time.
Good for you, a pain for the rest of us.
ogg_ogg
1.5 / 5 (4) Feb 20, 2016
Just because they're paranoid doesn't mean somebody isn't out to get them. We need some paranoia and gullibility (agreeableness) in the gene pool, makes War much easier to justify. I can't imagine any society surviving (although, my imagination is limited by my experience) for long without cannon fodder. So, we just have to tolerate the gullible, the paranoid, and the conspiracy nut jobs. Unfortunately.
viko_mx
1.4 / 5 (9) Feb 20, 2016
It is obvious for the honest and observant person how modern metaphysicians, descendants of the ancient shamans, are trying to explain the physical world in which we live with invisible and elusive for scientific equipment invented phenomena such as dark matter and energy, black holes and neutron stars, hidden dimensions and quantum fluctuations and infinitely elastic abstract geometric space without physical properties and limitations on which can be applied arbitrary mathematical operations and transformations, whatever the theory of relativity introduced. It is the base of the big bang mythology, which should provide billions of years for the mythology of biological evolution to look more realistically to people who donot know the structure of living organisms and cells. Once these people can not rely on scientific facts, remains to rely on imaginary phenomena that draw an imaginary world according to their passions and siritual attitudes which summarized is lawlessness.
viko_mx
1.4 / 5 (9) Feb 20, 2016
When they reject the very reason for the emergence and existence of life in the universe and on Earth to defend the status quo, for them remain only te option to offers highly speculative methaphysical theories that grossly violate the scientific principles.
The universe is highly organized physical environment with the finely tuned physical laws , constants and forces and when studing them we can see clearly the authorship of the Creator. These laws, constants and fundamental forces that have the purpose to maintain the originally established order in the universe are defined according to absolutes. There is only one naturaly stable in time system and this is the system that in based hol, eternal and unchangible God Who is the first cause of everything in the universe and Who can guarantee the absolute justice and the principles of life - the love and the truh for the whole eternity. Only this can guarantee abiding life in eternity
viko_mx
1.4 / 5 (9) Feb 20, 2016
The existance of the universe without the life in it is pointless.
B_Martin
1 / 5 (7) Feb 20, 2016
More pseudo science.. boring!
richmadjones
5 / 5 (8) Feb 20, 2016
The existance of the universe without the life in it is pointless.


Likely the inability to come to terms with this very thought is why humans invented God.
Phys1
4.1 / 5 (9) Feb 20, 2016
@viko_mx
The existance of the universe without the life in it is pointless.

Suppose there was no life in the universe, then there would be no one to care that its existence was useless. That is how useless your conjecture is.
torbjorn_b_g_larsson
4.1 / 5 (9) Feb 20, 2016
I didn't find the new paper, but here is an OA version. The basis is the Gondwanaland rotation and migration (traced by paleomagnetic data) and its correlation in time with the fossil record diversity. [ http://web.gps.ca...2015.pdf ; fig 1]

I wondered what would have riled a thread. When I saw the science was on the CE, I could guess the reason, irrelevant magic peddlers trying to stave off their anxiety about the universe being entirely without magic.

Here is an exquisite example: "The existance of the universe without the life in it is pointless."

The existence of magic belief without data in it is pointless.

[Luckily only magic peddlers lie awake over their pointless life. The rest of us create our own meaning.]
MR166
2.2 / 5 (5) Feb 20, 2016
There is something deep in man's Psyche that requires a belief in God, a superior being or beings. It is very hard find a society that did not hold these beliefs. Who am I to say that there is no God or that this is not a real human need. Logic only goes so far.
Maggnus
5 / 5 (7) Feb 20, 2016
If Earth experiences "true polar wander" what does that say about the stabilizing effects of the moon?


This is an interesting question, in that at first blush is seems to point out a conundrum. Except, it actually doesn't.

You are referring, I think, to theories of lithospheric slippage such as that suggested by Hapsgood and others.

The difference here is that it was a perfectly normal movement of the continents over the course of millions of years. So, it says nothing about the stabilizing effects of the moon - that theory is still just fine even with this slow-motion "lurch"

It helps when you read the whole article....
TheGhostofOtto1923
3.8 / 5 (10) Feb 20, 2016
The existance of the universe without the life in it is pointless
The assumption that it was created solely to enable the existence of life is baseless.
huckmucus
3.7 / 5 (6) Feb 21, 2016
"The existance of the universe without the life in it is pointless"

I've seen hundreds of feet of compressed-to-rock sediment four thousand feet above current sea level which settled to the bottom of a lifeless sea over the course of forever so long ago and I found a sign which read "On this spot in 2 billion B.C. nothing happened." And that doesn't include the rock around the star a million light years from here that is 7 billion years old and was never within thirty light-years of life. And right now, as I write, there is a doe, laying high on a mountain side, under a Juniper Tree, that will live and die and never see man and will never be seen by man and no one knows she's there and never will. I don't even know it. But it's true. And it does not matter. It never has and never will. It is Christopher Stone's ontological problem. And yours.
Monkey Butt
4.2 / 5 (5) Feb 21, 2016
@ MR166:

There is something deep in man's Psyche that requires a belief in Leprechauns. It is very hard find a society that does not hold these beliefs. Who am I to say that there are no Leprechauns, or that this is not a real human need? Logic only goes so far.

Or at least, in YOUR feeble mind, logic only goes "so far".
MorganW
not rated yet Feb 22, 2016
A fascinating concept, and as usual, the answers lead to even more questions.
torbjorn_b_g_larsson
4.5 / 5 (8) Feb 22, 2016
@MR: "Logic only goes so far."

That is why skeptics use evidence. If magic existed (say, something unnatural 'vanished' a pigeon or 'created' the universe), thermodynamics wouldn't work.
antialias_physorg
4.3 / 5 (7) Feb 22, 2016
"The existance of the universe without the life in it is pointless"

So? Who says the universe must have a point?
In the end life just defines itself as the point...which is sort of circular (and hence no argument at all for...anything)

It's a bit like being dead. Do you care when you're dead? Did you care that you weren't alive the first 13 billion years or so? No? And yet the universe still got along just fine without you (and will after you're gone)...even during the times when there was no life and when there will be no life.
AGreatWhopper
3.4 / 5 (5) Feb 22, 2016
viko_mx1.3 /5 (16) Feb 19, 2016
So called Cambrian explosion in fact is the Creation Event and is not happened before fictional 520 milion years ago but mutch recently about six tousand years ago.


The fact is that you are an oxygen thief and need to be prevented from continuing to commit the crime.
TheGhostofOtto1923
5 / 5 (5) Feb 22, 2016
There is something deep in man's Psyche that requires a belief in God, a superior being or beings
Even if this were true it is still not evidence of any kind whatsoever for the existence of any god, gods or goddesses.

It might simply mean that there is an endemic flaw in human beings. This flaw might be the same one which makes us so gullible to other sorts of fantasy, games of chance, trickery, and so forth.

Instead of assuming the worst (that these beast gods exist), it might be more fruitful to examine the flaw itself and see if it can't be fixed.
victoryengineer
3.7 / 5 (3) Feb 23, 2016
Wonderful. I go away for a few months and return to see our special friend viko_mx is still as delusional as ever. I wonder if it's genetic, trauma or drug born?
pnyikos
not rated yet Feb 23, 2016
This article gives a possible factor in somewhat speeding up the Cambrian explosion, but does not do justice to the biological side of the event. About twenty bilaterian phyla made their appearance within less than 20 million years, and except for some phyla that do not leave fossils, there has not been any new phylum coming into being since then. The geological events that are described in the article don't even begin to explain this phenomenon.
bschott
1 / 5 (4) Feb 24, 2016
viko_mx1.3 /5 (16) Feb 19, 2016
So called Cambrian explosion in fact is the Creation Event and is not happened before fictional 520 milion years ago but mutch recently about six tousand years ago.


The fact is that you are an oxygen thief and need to be prevented from continuing to commit the crime.


Coming from a fetus that likely had to play dodge the coat hanger to still be here....that's an ironic thing to say.

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