Study: Earth was warmer 500 million years ago, life exploded, and 'led to the start of the human race'

Tiny fossils unlock clues to Earth’s climate half a billion years ago. Sea temperatures of 25C helped fuel an explosion of life on Earth about 500 million years ago on Earth, according to UK scientists.

Scientists from the UK and France have quantified the temperature of Earth’s oceans over half a billion years ago by combining fossil data and climate models.

  • Study suggests early animals diversified in a greenhouse world, with a climate similar to that in which the dinosaurs lived
  • Chemical analysis was conducted on tiny fossils shells about 1mm long from blocks of limestone from Shropshire, UK, dated to between 515 – 510 million years old
  • Findings help to expand our knowledge of early animals and the environment in which they lived

Reflected light microscope images of some of the brachiopod fossils used in this study. They are not very pretty, but they are pretty useful for scientists researching ancient climates.


New research suggests that sea temperatures of around 25C (77F) and a lack of permanent polar ice sheets fuelled an explosion of species diversity that eventually led to the human race.

Scientists made the discovery while looking for clues in tiny fossil shells in blocks of Shropshire limestone thought to be around 510 million years old. (SkyNews h/t to Marc Morano)


From the University of Leicester:

An international collaboration of scientists, led by the University of Leicester, has investigated Earth’s climate over half a billion years ago by combining climate models and chemical analyses of fossil shells about 1mm long.

The research, published in Science Advances, suggests that early animals diversified within a climate similar to that in which the dinosaurs lived.

This interval in time is known for the ‘Cambrian explosion’, the time during which representatives of most of the major animal groups first appear in the fossil record. These include the first animals to produce shells, and it is these shelly fossils that the scientists used.

Scientists have long thought that the early Cambrian Period was probably a greenhouse interval in Earth’s climate history, a time when there were no permanent polar ice sheets.

Until now, however, scientists have only had a sense of what the Cambrian climate was like because of the types of rock that were deposited at this time – while it has long been believed that the climate was warm, specific details have largely remained a mystery.

Data from the tiny fossil shells, and data from new climate model runs, show that high latitude (~65 °S) sea temperatures were in excess of 20 °C. This seems very hot, but it is similar to more recent, better understood, greenhouse climates like that of the Late Cretaceous Period.

Thomas Hearing, a PhD student from the University of Leicester’s School of Geography, Geology and the Environment, explained: “Because scientists cannot directly measure sea temperatures from half a billion years ago, they have to use proxy data – these are measurable quantities that respond in a predictable way to changing climate variables like temperature. In this study, we used oxygen isotope ratios, which is a commonly used palaeothermometer.

“We then used acid to extract fossils about 1mm long from blocks of limestone from Shropshire, UK, dated to between 515 – 510 million years old. Careful examination of these tiny fossils revealed that some of them have exceptionally well-preserved shell chemistry which has not changed since they grew on the Cambrian sea floor.”

Dr Tom Harvey, from the School of Geography, Geology and the Environment, added: “Many marine animals incorporate chemical traces of seawater into their shells as they grow. That chemical signature is often lost over geological time, so it’s remarkable that we can identify it in such ancient fossils.”

Analyses of the oxygen isotopes of these fossils suggested very warm temperatures for high latitude seas (~65 °S), probably between 20 °C to 25 °C.

To see if these were feasible sea temperatures, the scientists then ran climate model simulations for the early Cambrian. The climate model simulations also suggest that Earth’s climate was in a ‘typical’ greenhouse state, with temperatures similar to more recent, and better understood, greenhouse intervals in Earth’s climate history, like the late Mesozoic and early Cenozoic eras.

Ultimately, these findings help to expand our knowledge of the early animals of the period and the environment in which they lived.

Thomas Hearing said: “We hope that this approach can be used by other researchers to build up a clearer picture of ancient climates where conventional climate proxy data are not available.”

The research was carried out as an international collaboration involving scientists from the University of Leicester (UK), British Geological Survey (BGS; UK), and CEREGE (France). This collaboration brought together expertise in geochemistry, palaeontology and climate modelling to tackle this longstanding problem.

The scientists have co-authored an open access (publicly available) paper in the journal Science Advances.


The above paper is at the following url: http://dx.doi.org/10.1126/sciadv.aar5690

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SMC

Huh, so a warmer Earth is better for life it seems. How ’bout that.

zazove

Yeah, that’s the Sunday School message. But the opposite is true for homo sapiens.
A lot of planets had to line up for it to get cold enough for our species to evolve. We only appear after the red line dips below zero.comment image
So I guess that must mean cold is better.

MarkW

In what laughably passes as your mind, you are actually declaring that since it it was generally cooling while humans evolved, this proves categorically that it has to be cool for humans to survive????
The fact that humans need to wear clothes almost everywhere they live in order to keep themselves warm isn’t relevant?
The fact that it’s been as much as 5C warmer during the last 20K years (a time where modern humans already existed) and humans thrived isn’t relevant?
Are you as desperate as you make yourself sound?

Felix

While the world did cool after the formation of Antarctic ice sheets some 34 Ma, our ancestors were tropical animals and those which did live in temperate Europe and Asia did so during epochs much warmer than now.
The fact that grasslands were spreading and forests shrinking during the Miocene, Pliocene and Pleistocene doesn’t mean that humans need cold to survive. We are an African animal which has achieved a global distribution because our cultural adaptations allow us to stay warm even in cold climes.

zazove

I’m just drawing your attention to the graph Mark. You can flail your arms around as much as you like, it doesn’t change the temperatures homo sapiens have endured.

zazove

This is what a bit of cold could do for you:comment image

Felix

Zazove,
It wasn’t cold in tropical Africa, where humans evolved. Their world was drier, thanks to a cooling world, but still warmer than now. Our ancestors adapted to the cooling by evolving, then by developing culture, ie stone tools, fire and clothing.

HotScot

zazove
And atmospheric CO2 was where during your 65M years ago?
http://www.biocab.org/Geological_Timescale.jpg
Oh! Look……….nowhere near temperature!
And look where CO2 has been for the last 3M years or so. Bumping along the baseline of meaningful plantlife survivability around 150ppm until, guess what?
Yep, we homo sapiens arrived, discovered fire, then fossil fuels, and miraculously saved the planet from extinction by liberating all that naturally, but accidentally sequestered CO2.
Damn, but we’re good!

Ray in SC

Zazove,
The ‘0 degrees’ mark on your chart represents the difference in temperature (ie. anomoly) compared to the present, not the actual temperature at that time. Having said that, it is interesting that the chart shows the present temperature having a -2.5C degrees difference when compared to…the present temperature.

zazove

Ray, I think “Before Present” means before 1950.
https://en.wikipedia.org/wiki/Before_Present

Stephen Richards

DON’T FEED THE TROLL.

old white guy

try growing food in ice.

MarkW

No zazove, you are interpreting the graph, and doing so in a highly unintelligent manner.

MarkW

How does comparing three modern animals prove that humans only evolved because it became colder?
It became colder just as fast for the Chimpanzee and Bonobo.

Samuel C Cogar

zazove – May 10, 2018 at 2:56 pm

A lot of planets had to line up for it to get cold enough for our species to evolve.

OH GOOD GRIEF, ……. our species (Homo) is the only known per se “naked ape” in the Family of Great Apes ….. and thus it had to have been an extremely warm to hot environment for tens of thousands of years during their evolution to become the walking, talking, naked ape in the family.
The only thing that makes sense in the evolution of Homo sapiens sapiens, as an extant member of the Family of Great Apes, is that our pre-human ancestors evolved in an environment where they maintained a close relationship with a large body of water such as a large salty lake, inland sea or tidal zone from which they could EASILY harvest an abundant supply of high-protein foods with very little effort on their part. And it t’was their “wading” in the salty water to harvest their food that resulted in the evolution of bipedalism and the loss of most of their protective body hair. And their ingesting of a “high salt” diet resulted in their evolving of “salt emitting sweat glands” for easily ridding the body of excess salt.

Samuel C Cogar

zazove – May 10, 2018 at 9:18 pm

Ray, I think “Before Present” means before 1950.

Don’t be talking “trash”. ……. Intentionally voiced CYAs irritate me quite easily.
Only iffen “Before Present” was stated, uttered or written in 1950 …. would it mean before 1950. The “present” is the “present”, …… it ain’t yesterday and it ain’t tomorrow.

Felix

Samuel C Cogar May 11, 2018 at 8:22 am
Sorry, but there is no support for that baseless conjecture.
Sweat glands evolved as part of a complex evaporative cooling system, which includes relative hairlessness. This system was an adaptation to our evolution of a grassland hunting lifestyle featuring long distance bipedal running. We got the fat needed for larger brains from large terrestrial animals, not fish. The isotope content of fossils shows this, as does our technology, such as the hand ax which was our Swiss Army knife for about a million years. It was ideal for breaking open the long bones of predated or scavenged megafauna to get the marrow, or skulls to obtain the brains. Females of our evolving genus could also use the “ax” for digging up tubers.
Obviously, as Mark points out, evolving in the warm tropics made hairlessness possible.

Felix

PS: However later, fully modern humans did start to exploit aquatic and marine food resources, by 120 Ka or possibly earlier. Our culture and technology also allowed us to enter the subtropical and temperate zones, even in a cooling world, or just during the balmy Eemian interglacial.

Samuel C Cogar

Felix – May 11, 2018 at 2:37 pm

Samuel C Cogar May 11, 2018 at 8:22 am
Sorry, but there is no support for that baseless conjecture.

Shur nuff, Felix, ….. shur nuff.
And there is no support for that baseless conjecture of plate tectonics.
And there is no support for that baseless conjecture of bacteria causing stomach ulcers.
And there is no support for that baseless conjecture of evolution via descent w/modification .
And there is no support for that baseless conjecture of …. (Felix, pick 1 of several dozen)
Felix, I appreciate and welcome your response, …….. BUT, ………. your mimicry of the silly pseudo-science claims of human evolution doesn’t impress me in the least. But it does prove you don’t think for yourself and that you readily accept what you are taught by your mentors as being “gospel truth”.
Felix, your posted comment was a perfect example of “circular reasoning” whereby you …. “put the cart before the horse” …. in everything you claimed was a fact of evolution.
How was it possible for early humans to have invented hand axes …… for killing n’ butchering large animals for the protein and fat needed for evolving an intelligent brain …… prior to their evolving an intelligent brain …… which was prerequisite for them to be doing any inventing of hand axes?
Felix, how did our pre-human ancestors SURVIVE the 1st million years out on the hot savannah grasslands while they were evolving the ability to walk bipedally, ….. let alone run bipedally?
And Felix, …… try to picture a naked (hairless) pre-human in search of “brain food”, …. running recklessly across the African savannah through the brush, briars, thorns, stinging bees, biting insects, poisonous reptiles and the sharp claws and teeth of predator animals intent on taking a “bite” out of their arses.
Felix, bipedal pre-humans, like bipedal modern humans, can’t outrun most quadrupedal predator animals, …. plus the fact that predator animals didn’t need to actually see early humans in order to get close enough to kill them, …… they could smell and/or hear the pre-humans from 100 yards away.
And Felix, please tell me why, early humans would have evolved hairlessness and sweat glands to dissipate the excess body heat being generated by their bipedal running across the hot African savannah, when said profuse “sweating” required for evaporative “cooling” of their body, also rid their body of two (2) of the most essential, most important, things required for keeping them alive, …… water (H2O) and salt (NaCl).
Felix, please don’t be telling me that early humans pre-invented containers for carrying salt and water with them when chasing after the “brain food” they needed for inventing “hand axes” that they needed for killing and butchering the animals to get said “brain food”.
And ps Felix, iffen early humans lost their “fur coat” after migrating out onto the hot, dry savannahs, ….. me thinks the 1st things they should have invented would have been band-aids and insect spray.
Felix, iffen one is living along the shoreline, no tools, especially “hand axes”, are required for harvesting and eating the dozens of HIGH PROTEIN food items that can be caught/scavenged from the shallow waters. And what better place to evolve bipedalism ….. than to be “walking” around in waist-deep water?

Trevor

Humans evolved because they HAD TO. Our ancestors could not have survived the colder climate that we have, so they evolved. Into us. But that doesn’t mean we can’t survive a warmer climate. Our ability to reason alone gives us a huge advantage over both the climate and other animals. We are no longer dependent on Mother Nature to provide fruits and berries to sustain us. We grow our own food. Because we HAD to in order to survive. And we are not going to FORGET how to grow food just because the climate warms a few degrees (in fact, yields and growing area will INCREASE if global warming continues … too bad it’s over). And thanks to our scientific advances (and the abundance of fossil fuels), we really don’t give a damn about the climate because we can stay comfortably warm in the winter and comfortably cool in the summer. So cry not for humanity. We will be fine.

Felix

Samule,
Your baseless conjecture for HGT is not a scientific hypothesis. You can’t make predictions on its basis and test them by experiment.
OTOH, it’s easy to show the specific genetic mutations which account for the differences among related groups of plants, animals, fungi and microbes.
None of your imagined arguments against the objective fact of human evolution make any sense at all, and are all readily shown false.
Members of the dog family also lose water when cooling off by panting. They find more on the African plains without carrying any water with them.
The hand ax and brain evolution went hand in hand, so to speak. We know the specific mutation which accounts for human brain growth, and from fossils we can see how long it took for our brains to reach their present size.
All the evidence in the world shows that humans and other organisms have evolved.
You OTOH cannot cite a single shred of evidence in support of your fact-free assertion that animal phyla arose in the Cambrian from HGT. Again, I ask, which genes were transferred from whom to whom to create each new phylum?
Thanks.

Felix

Samuel,
Sorry for the typo.
It’s ludicrous to compare your baseless conjecture with real scientific hypotheses like Wegener’s. Those scientists had evidence for their hypotheses. You’ve got nothing.
You’re not thinking out of the box. You’re simply making a WAG without a shred of supporting evidence.

Felix

Showing key innovations, caused by mutations and natural selection, in the evolution of animal phyla:comment image

Felix

Samuel,
Thinking out of the box first requires thinking.
So please think about how these innovations could have arisen by HGT, then write up your conclusions in a real scientific paper.
HGT can be a source of genetic variability, but unless you can point to the transferred material which led, for example, to the molluscan radula, then all you’re doing is engaging in idle, unfounded speculation.
Its evolution, OTOH, is well supported by every possible line of evidence. A paper from just last month has clarified which genes mutated to form the radula:
Novel Genes, Ancient Genes, and Gene Co-Option Contributed to the Genetic Basis of the Radula, a Molluscan Innovation
https://academic.oup.com/mbe/advance-article/doi/10.1093/molbev/msy052/4956465
An earlier study:
Evolution of the Radular Apparatus in Conoidea (Gastropoda: Neogastropoda) as Inferred from a Molecular Phylogeny
file:///C:/Users/Administrator/Downloads/Kantor_PUillandre_2012_Malacologia.pdf
You really ought to study biology before presuming to make wild a$$ guesses about it.
Similar genetic, morphological and other lines of evidence exist for the evolution of key distinguishing traits for other animal phyla.

Felix

IOW, changes in the genes already present in the lophotrochozoan ancestors of mollusks enabled the evolution of the radula, in an instance of natural selection.

Felix

MarkW May 11, 2018 at 7:25 am
That comparison only proves that Zazove is either a troll or an idiot, or both.

Felix

Samuel,
Similarly for the largest of all animal phyla, Arthropoda (Mollusca is Number 2). The genes for chitin, the material of the arthropod exoskeleton, exists not only in other animals, but in fungi and plants as well. Hence, another instance of an innovative use of genes already present. No need for your imaginary HGT, yet again.
Evolution and multi-functionality of the chitin system
https://link.springer.com/chapter/10.1007/978-3-0348-7527-1_33
Chitin, that is, the β-1, 4 linked polysaccharide of N-acetylglucosamine, is best known as a cell wall component of fungi and as skeletal material of invertebrates. In recent years this simple picture has changed dramatically. Three developments have taken place: the discovery of chitinous tissues in vertebrates, the molecular analysis of the chitinsynthase genes, and the discovery that chitin derivatives play a crucial role in the interaction between higher plants and symbiotic bacteria. In this paper the methods for chitin detection and the current data on the evolution of chitin synthesis are reviewed. In addition, data is summarized which suggest that chitin synthesis may serve roles other than the production of skeletal material. In particular, anecdotal evidence suggests that chitin derivatives may play a role as signals in plant as well as animal development. Two major unresolved questions are identified: 1) Is there historical continunity of all the chitin synthesizing systems in protists, animals and, in particular, the deuterostome animals. 2) Are chitin derivatives actually involved in the development of plants and animals?
By the same token, chordates, ie we and our relatives, build our endoskeletons with the ubiquitous animal (also present in our colonial unicellular choanoflagellate ancestors) connective protein collagen, mineralized to a greater (vertebrates) or less extent (hagfish, lampreys and cartilaginous fish, such as skates, rays and sharks) with calcium. We also share a notochord or equivalent with our non-chordate relatives.
Evolution of the notochord
https://evodevojournal.biomedcentral.com/articles/10.1186/s13227-015-0025-3
So, once more, not HGT called for.
Good luck with writing up and defending your baseless conjecture and wild speculation.

Duster

You use a plot that misrepresents things profoundly. You’ve cherry picked a chart that covers only the Holocene – 65 million years more or less. You thus avoid any actual comparisons with the rest of the Phanerozoic and, whoever produced that plot lied blatantly about the “mean” temperature of the Holocene which would be the only “present” you could refer to that is even slightly warmer than “now.” To make the point you want you should use the average Pleistocene temerpature and that still leaves open the question of whether our genus didn’t actually appear earlier, as in the late Pliocene.
The “present” including the Holocene, the Pleistocen and at least the later Miocene is comparable climatically and in CO2 trends over similar time spans with the Permian – 250 MYA. The take home of that is that the Permian ended in a glacian epoch with pronounced sea level drops (not warming as the CO2 worriers like to claim with only models to support them). And, given other terminal Permian data (not models) the planet was impoverished in available CO2, and oxygen levels were decreasing in the marine environments. The latter should sound familiar, and the former is more than likely the chief cause of various conditions like extensive global distributions during the last galcial epoch. Right now, CO2 levels are barely “safe.” Halve them and we could be seeing serious, planet wide ecological collapses – like th Permian. We can survive a warmer planet, but a colder one may be very bad..

Zazove you are working with fake news.
Those numbers have been screwed around with by your favorite global warmers.
PETM temperatures were about +6.0C, not +16.0C. So you have to ask yourself, is anything these guys tell you the truth?
If you used the same scaling method and went back to the Cambrian explosion period, temperatures would be about +50.0C.
Sorry this happened to you.

zazove

Found that graph here Bill, can’t trust anyone these days.
https://wattsupwiththat.files.wordpress.com/2011/12/image29. png
Apart from that, what “fake news” are you referring to? Evolution?
Sorry you missed my point btw.

Robert of Ottawa

A warm planet is a happy planet.

Latitude

models again…..makes you wonder
In a sane world…people would be asking why did it get colder

SMC

That’s easy, Climate Change made it colder. 🙂

L, the models were not climate models. They were plate tectonic models to estimate originating latitude. See long comment below just posted. Spent some hours reading the paper and brushing up on previous knowledge.

Latitude

ah!……thanks…
I think your long post got lost in wordpress….I hope you saved it!

Felix

Same as happened to me. Twice so far in these comments.

HotScot

Latitude
Ah! Computer models. The first thing I looked for.
I’m getting better at this climate malarky.

zazove

More recently it got really cold and dry allowing homimids to diverge from chimps. By 75,000 years ago we were primed and ready to infest during a goldilocks interstatial. Now the next 50 years is going to test our adaptability.

MarkW

Adapting to a world that is more friendly to life.
I like easy challenges.

kaliforniakook

Ditto.

rocketscientist

Hmmm…if it get too easy won’t we just become more prolific?

Rich Davis

Hmmm…if it get too easy won’t we just become more prolific?

How many kids do you have rocketscientist?
I am an anomaly who had four. My wife and I can tell you that as much as we love them all, it was not easy raising them. We didn’t need them to work the fields. None of them died in their childhood or infancy. I have only two friends or relatives who have as many kids as I do, and many who have one or none.
The empirical facts are that human fertility drops as prosperity rises. Compare Japan or Italy to Bangladesh or Malawi. Compare Japan or Italy in 2018 to Japan or Italy in 1918.

zazove

See my Sunday School comment below.

Felix

Humans have easily survived thousands of years much warmer than 560 ppm CO2 can possibly make the world. And not just during the Holocene. Fully modern humans and our close kin the Denisovans and Neanderthals also flourished during peak Eemian heat.
CO2 presents no problems to which we can’t adapt.

zazove

“Eemian heat” is barely distinguishable from Holocene heat and CO2 levels are now abruptly 40% higher and spiking.
Good luck.

MarkW

Just because you add a chart to a ridiculous claim, it doesn’t become less ridiculous.

MarkW

If 7000ppm couldn’t spike temperatures, I doubt 560ppm will.

Felix

zazove May 10, 2018 at 2:40 pm
The Eemian was warmer than the Holocene Optimum by a significant degree, and it lasted 5000 years longer than the Holocene so far. Times were good.
The effect of doubling CO2 on temperature is negligible and highly beneficial for the vast majority of crops and all trees.

zazove

Warmer, significant, good, negligible, highly, vast and all.
Extraordinary effort massaging them into two and a bit sentences.
Got any facts?

Felix

zazove,
All facts. Unlike CAGW, which is based upon evidence-free GIGO models with unphysical assumptions.
In the Eemian, hippos swam in the Thames at the site of London, trees grew above 71 degrees N latitude and raised beaches formed in Alaska and elsewhere in the world. The Southern Dome of the Greenland Ice Sheet melted about 25% more than it has during the Holocene. Scandinavia was also an island, but that was mainly from the weight of ice during the previous glacial.
Maybe these facts aren’t significant to you, but they are to paleoclimatologists.

Felix

You don’t consider the greening of Earth thanks to four rather than three molecules of plant food per 10,000 air molecules to be a good thing?

JL

“CO2 levels 40% higher.” Using percentages, especially in this case, can be highly misleading. We’re told it’s the concentration that counts (hence the ppm designation). “40%” tells one nothing about CO2 concentration.

HotScot

zazov
“Warmer, significant, good, negligible, highly, vast and all.
Extraordinary effort massaging them into two and a bit sentences.
Got any facts?”
OK, as a non scientist, let me try.
The fact is, as far as I can ascertain, the only observable i.e. empirical manifestation of increased atmospheric CO2 is that NASA tells us the planet has greened by 14% in the last 30 years. One of the researchers described it as two continents the size of mainland America worth of extra vegetation.
So far, as far as I’m aware, no one has actually empirically demonstrated that CO2 causes the planet to warm by any great degree, and certainly not as much as the IPCC would have us believe from their computer models.
David Middleton disagrees with me in that he says there is a paper that proves CO2 causes the planet to warm, but I’m not sure by how much. In any event, it’s not even used by alarmists and the only other one I’m aware of is a fake as it measures temperatures from the depths of a La ninia to the heights of an El Ninio.
All in all, it suggests to me as a layman that whilst CO2 is rising (as measured from the top of a volcano, humanities best attempt at measuring it) it’s a trace gas, unevenly distributed across the planet, which has proven to be nothing but beneficial. Far and away swamping any supposed detrimental effect, quite apart from being the only observable effect.
But I hear you say you’re concerned about temperature alone. Again, as far as I’m aware, increased temperatures will be more evident at night, across northern and southern latitudes, rather than during the daytime, around the equator.
But then the poles will melt and flood us all out our homes.
Sadly, if one is stupid enough to build a home on a river estuary (as many in the world are) or on flood plains, then may hell slap it into you. You reaped the benefit when times were good, if times get tough, tough.
We live in changing times. Man is adaptable or we couldn’t survive in space, which we don’t do without heat, by the way.

Felix

Zazove,
London with hippos on its banks is IMO easily distinguishable from present lack thereof. Ditto trees in the High Arctic.

MarkW

HotScot, you are demanding the impossible.
Most scientists hold that the climate sensitivity to a doubling of CO2 is under 1C, probably under 0.5C.
Since climate variability is as much as 3C to 5C and our ability to actually measure the temperature of the planet didn’t exist prior to the satellite age, it’s impossible to pick out a signal that small in all that noise.
Now you chose to declare that since a signal can’t be measured, that proves it doesn’t exist.
But that’s your choice, it isn’t a scientifically accurate statement.

Samuel C Cogar

HotScot – May 10, 2018 at 4:57 pm

So far, as far as I’m aware, no one has actually empirically demonstrated that CO2 causes the planet to warm by any great degree, and certainly not as much as the IPCC would have us believe from their computer models.
David Middleton disagrees with me in that he says there is a paper that proves CO2 causes the planet to warm, but I’m not sure by how much.

Hang in there, HotScot, …. there has never been any actual factual proof or evidence presented that proves atmospheric CO2 quantities of less than 10,000 ppm, or even 15,000 ppm, causes any measurable “warming” of the earth’s near-surface atmosphere.
Hells bells, the proponents of CAGW and most of the non-proponents REALLY DON’T want anyone to DISPROVE the “CO2 warming claim”. Their livelihood, job status and/or career is dependent on the “status quo” remaining as it is, …… otherwise they would be demanding that an actual, factual PHYSICAL scientific experiment be conducted to prove or disprove the CAGW hypothesis.
A “simple” experiment that any one of 50,000+ individuals or groups could easily perform.
And ps, HotScot, ….. don’t let David Middleton’s disagreeing bother you in the least. “DUH”, there is no published paper that presents literal proof or factual evidence that CO2 causes the planet to warm. Said paper may employ some “fuzzy math calculation”, mimicry, insinuations, guesstimations and weirdo extrapolations.

Samuel C Cogar

MarkW – May 11, 2018 at 7:31 am

[response to HotScot,] “…………. it’s impossible to pick out a signal that small in all that noise.
Now you chose to declare that since a signal can’t be measured, that proves it doesn’t exist.
But that’s your choice, it isn’t a scientifically accurate statement.

MarkW, are you delusional, or what?
How can you honestly claim there is a “signal” present ….. while at the same time you are claiming that it’s impossible to detect said signal.
I’d be more apt to believe you iffen you claimed to have detected the presence of the Flying Spaghetti Monster on the dark side of the Moon.

MarkW

Simple, the math and the science says it should be there.

Samuel C Cogar

MarkW, ….. GETTA CLUE, ……. “saying it should be there” ……. and proving it is there, ….. are two (2) completely different thingys.
Einstein claimed that gravity would “bend” light rays, …….. but it took several years and a solar eclipse to prove him correct.

Rich Davis

I don’t see any reason to expect that. Are you anticipating a sharp cooling period? That seems unlikely, at least in the extremely short time frame of the next 50 years. It seems to me that the most likely outcome of the next five decades will be another half degree of warming and higher agricultural productivity from a combination of more plant food (CO2), better water utilization by plants at higher CO2 concentrations, and more arable land due to plants being able to survive in formerly desert environments. All of this should lead to a planet able to support 15 billion people (but probably only supporting 8 or 9 billion), with much higher standards of living than today.

Gary Pearse

Right on. I’ve coined “Garden of Eden Earth” in the last year or so in light of the unexpected galloping greening that the Team avoids discussing like the plague. My addition has been that the greening is an endothermic process, so warming will be moderated by it.

HotScot

Gary
I love greening. I’ll talk to you about it as much as you want.

Another Scott

The next 50 years will test our adaptability. Ok, prove it.

Carbon Bigfoot

As Steven C. Meyer indicates in “Darwin’s Doubt”……The explosive origin of animal life and the case for intelligent design, there is no scientific evidence for divergence from chimps as you suggest, zazove. The Pre-Cambrian Explosion, 530 mm yr. bpd with its high CO2 levels and elevated temperatures is when most life started. Humans did not evolve from chimps or apes. Other intervention was necessary. I’ll leave that to critical thinkers and ancient archeology proof that is beginning to surface.

Felix

Big,
About this, Zazove is right.
All the evidence in the world shows that humans and chimps diverged from a common ancestor. Before that, the gorilla ancestor split off from those African apes ancestral to humans and chimps. Before that, African great apes diverged from orangutans.
Sorry, but those are the facts, as shown by every single possible line of evidence, with not a shred of scientific evidence against that inescapable conclusion.
OTOH, there is zero evidence for “Intelligent Design”. If we were designed, the Designer was intensely Idiotic.
Most life did not start in the Cambrian. That’s just when a number of large animal phyla with hard body parts are first evident in the fossil record. Before that time, their ancestors were small, soft and yet to evolve some characteristic features of their phyla.

Felix

A few genetic similarities and differences between humans and chimps:
Not just differences in genes, ie protein coding sequences of the genome, but control switches which turn processes off and on, such as our short body hair v. other apes’ longer coats, make us different:
https://www.amnh.org/exhibitions/permanent-exhibitions/human-origins-and-cultural-halls/anne-and-bernard-spitzer-hall-of-human-origins/understanding-our-past/dna-comparing-humans-and-chimps
The large human Chromosome #2 resulted from the fusion of two smaller, standard great ape chromosomes: This gross chromosomal mutation is associated with upright, bipedal walking.
http://www.evolutionpages.com/chromosome_2.htm
Our brain growth and jaw reduction were triggered by a single mutation about 2.4 Ma:
http://articles.baltimoresun.com/2004-03-25/news/0403250090_1_human-evolution-gene-mutation
After slow, steady growth in brain size for over two million years, another mutation just ~200 Ka made us even smarter:
https://www.theguardian.com/technology/2010/mar/28/colin-blakemore-how-human-brains-got-bigger
Some other beneficial mutations making us who we are now:
https://www.newscientist.com/round-up/accidents-human-evolution/
Meanwhile, chimps were also of course evolving away from our last common ancestor.

WXcycles

Oh take some valium zazove, we all die, no need to get so freaked-out about it. If you really figure we’re stuffed because of CO2, well good for you, you’re a superior being, obviously, and we’re fortunate to drink at your smug and smarmy font of wisendom, thank you so much.

Ken Mitchell

I’m concerned with them trying to validate a proxy for an unavailable temperature measurement against a computer simulation that itself has no actual data. What actual data is being fed into this circle?

Felix

The shelly fossils are a form of paleoclimatic proxy data.

MarkW

Yesterday we got sidetracked talking about Sally, now you want to talk about Shelly.

M Courtney

The Cambrian Explosion led to human life?
Well Yeah… Eventually.
There may have been a few intervening steps though. It might all be more complex than it first appears.

Felix

So did the origin of life some 3.5 billion years earlier, too, and its subsequent evolution down to 541 Ma, the start of the Cambrian.
The big news for human evolution from the Cambrian is fossils of tiny chordates, the first in our phylum. Protochordates probably lived in the latest Precambrian Supereon (Neoproterozoic Era), among the Ediacaran fauna, but I don’t think that any definite fossils have been found. They would have been itty bitty deuterostome bilaterians.
Every geologic period of the Phanerozoic Eon has featured animals ancestral to humans, obviously. Chordates and vertebrates in the Cambrian, jawed fish in the Ordovician, bony fish in the Silurian. lobe-finned fish and tetrapods in the Devonian, amniotes and synapsids in the Carboniferous, therapsids in the Permian, protomammals (or mammals, depending upon your definition) in the Triassic, mammals in the Jurassic, placentals in the Cretaceous, primates (possibly earlier, again depending) and catarrhines in the Paleogene and apes and humans in the Neogene.

Felix

My comment failed to post. I’ll give it a while to appear from its trip through cyberspace before trying again.

Felix

Sorry if reposting leads to a double:
So did the origin of life some 3.5 billion years earlier, too, and its subsequent evolution down to 541 Ma, the start of the Cambrian.
The big news for human evolution from the Cambrian is fossils of tiny chordates, the first in our phylum. Protochordates probably lived in the latest Precambrian Supereon (Neoproterozoic Era), among the Ediacaran fauna, but I don’t think that any definite fossils have been found. They would have been itty bitty deuterostome bilaterians.
Every geologic period of the Phanerozoic Eon has featured animals ancestral to humans, obviously. Chordates and vertebrates in the Cambrian, jawed fish in the Ordovician, bony fish in the Silurian. lobe-finned fish and tetrapods in the Devonian, amniotes and synapsids in the Carboniferous, therapsids in the Permian, protomammals (or mammals, depending upon your definition) in the Triassic, mammals in the Jurassic, placentals in the Cretaceous, primates (possibly earlier, again depending) and catarrhines in the Paleogene and apes and humans in the Neogene.

See long comment below. The Cambrian explosion was a truly seminal event in the evolutionary history of life. Read S. J. Gould’s 1989 book Wonderful Life to get an overview from a true genius Harvard polymath: professor of geology, paleontology, and biological evolution!

Felix

Gould was wrong, as about so much else.
To the extent that there was a Cambrian “explosion”, it occurred early in the period, with increased biomineralization. Eyes too were evolving in the early Cambrian.
https://www.cambridge.org/core/journals/geological-magazine/article/chronology-of-early-cambrian-biomineralization/506BB3B68F4D4B8268B113535B1D748F
The “explosion” is best seen as recovery of diversity from the end-Ediacaran mass extinction event (MEE), caused by animals having consumed the basis of their then food chain, bacterial slime mats on the seafloor. One response to this crisis was an increase in predation, which put a premium on vision and hard body parts. But this process was far along by the time of the Burgess Shale.
The Triassic is also seen as a period of “explosive” diversification, following the end-Permian “Great Dying” MEE.

Felix

Again, the PR release overeggs the sauce. Science had already concluded that the mid- and late Cambrian were warm. This study might help improve precision as to SST in the mid-Cambrian.
The early Cambrian however was still cold, despite enjoying about 7000 ppm of photosynthesis feedstock gas (although land plants hadn’t evolved yet). There were likely polar ice caps and a series of glaciations, as the planet was still recovering from the Neoproterozoic Snowball Earth episodes. The continent of Gondwana still covered the South Pole, cutting off polar ocean currents.
Earth warmed towards the end of the period; the glaciers receded and eventually disappeared, and sea level rose. Thus, average temperature for the period has been estimated at seven degrees Celsius higher than today. The warming trend continued into the Ordovician Period, which ended in another Icehouse interval, again despite CO2 levels around 4500 ppm.

CO2 good…comment image
Warm good…comment image
Life is good…comment image
It’s all good.

zazove

CO2 good, warm good, therefore more CO2 and warm must be good. If I had ever gone to Sunday school – this would remind me of it.

MarkW

When a bad idea gets stuck in your “brain”, you never let go.

zazove

Like: more CO2 and warmer must be good?
Exactly. Spot on. Nailed it.
Try to let it go.

JL

Good job-you got it right

MarkW

That warmer is better is proven.
That CO2 is good for plants is proven.

Kristi Silber

When the solar luminosity is combined with CO2 levels, the result correlates much better with Phanerozoic temps. than looking at either one alone. The sun was 4% cooler 500 million years ago, and that has to be taken into account.
See http://droyer.web.wesleyan.edu/PhanCO2(GCA).pdf, for example.
“Many factors are important in controlling the average surface temperature of the Earth, including solar luminosity, albedo, distribution of continents and vegetation, orbital parameters, and other greenhouse gases. The message of this study is not that atmospheric CO2 is always the dominant
forcing (see Section 3.7 for an early Paleogene example). Instead, given the variety of factors that can influence global temperatures, it is striking that such a consistent pattern between CO2 and temperature emerges for many intervals of the Phanerozoic. This correspondence suggests that CO2 can explain in part the patterns of globally averaged temperatures during the Phanerozoic.”
CO2 has in the past had an effect on global temps, although changes in the sun’s energy have often been the driver of >>change in direction<< of warming/cooling. CO2 buildup in the atmosphere is likely what changed the planet from a snowball to warm ball. Biologic and then geologic sequestration bury CO2, lowering atmospheric levels, and consequently, temperatures.

John Bell

404 error not found

MarkW

The sun wasn’t 4% cooler 100 million years ago when CO2 was up around 5000 ppm.
Face it, there is no correlation at all between CO2 and temperature in the proxy record.

Latitude
Latitude

well link still didn’t work…..John highlight copy and past to the pdf at the end

Gary Pearse

Kristi, having to fiddle all the time to make CO2 work right to produce the temperatures tells one that one has fallen in love with an idea that is much lesser a player than one thinks. I imagine one could cobble a theory of gravity that depends on CO2 using the same acrobatics with other factors.

MarkW

The sun’s increase in output is pretty close to constant.
On the other hand plotting CO2 vs temperature for the last 500 million years is pretty much a random walk.
Plotting CO2 and solar output together may increase the r value by a teeny bit, but it’s still pretty close to a random walk.

WBWilson

Kristi,
Try reading this recent paper on the correlation of paleotemps with CO2 over the last 425 My.
“The Relationship between Atmospheric Carbon Dioxide Concentration and Global Temperature for the Last 425 Million Years,” by W Jackson Davis.
His conclusion: “This study demonstrates that changes in atmospheric CO2 concentration did not cause temperature change in the ancient climate.” Not exactly earth-shattering news, but he uses updated T and CO2 datasets and subjects them to robust statistical analyses, and has some nice graphs.
http://www.mdpi.com/2225-1154/5/4/76?utm_source=TrendMD&utm_medium=cpc&utm_campaign=Climate_TrendMD_0

Rich Davis

This chart has to be fake, right zazove & Kristi? Two out of four ice ages show CO2 rising before glaciation and being 5-10 times higher concentration than today. The variation in both CO2 concentration and temperature over the period is so much greater than any variation in the modern period. And look how CO2 lags temperature both on the way up and on the way down.
If I grasp your point of view correctly, lower insolation explains how 10x the CO2 still led to the Ordovician ice age and then swung around to an 8 deg 4deg temperature anomaly.

How do you explain Jurassic and Ordovician ice ages when CO2 was 2,000 and 4,000 ppm? Pangea in the south pole?

Javier

We already had Veizer’s work and curves to tell us the same. The world has been warmer than the current Ice Age for > 95 % of the past 600 million years, and warmer than the present interglacial for > 60 % of the time. But their model is busted. Sea surface temperature doesn’t get above 30°C. Near that temperature deep convection prevents it from warming. It shows models can’t be trusted.

Felix

A number of studies has found SST above 30 degrees C for the hottest part of the Cretaceous:
Cretaceous sea-surface temperature evolution: Constraints from TEX86 and planktonic foraminiferal oxygen isotopes
https://www.sciencedirect.com/science/article/pii/S0012825217303859
“Overall, our compilation shows many stratigraphic similarities with other records of Cretaceous climate change, including benthic foraminiferal δ18O records, with both SST proxies indicating maximum warmth (SSTs > 30 °C at low and lower mid-latitudes) in the Cenomanian–Turonian interval (97–90 Ma). Similarly, both δ18Opl- and TEX86-SST estimates indicate prolonged cooling of the surface ocean and possible changes in ocean heat transport in the Late Cretaceous through the Coniacian–Santonian to the end-Maastrichtian interval.”
One hypothesis for Cretaceous heat is that the oceans were too hot to produce the biological CCNs needed for cloud formation.

Javier

An alternative is that they have a calibration problem. SST > 30 °C require that the physics of the climate system operated in a different manner, and extraordinary claims require extraordinary evidence. The Cretaceous is pretty recent in geological terms, and without a similarly operating cloud system the climate would have had to operate very differently. No evidence of that.

tty

One big problem with the HEX86 proxy is that temperatures over about 30 degrees have to be extrapolated since there are no recent sediments sourced from water warmer than that.
Another, and perhaps bigger, problem is that the HEX86 values from the hottest and saltiest sea today (the Red Sea) are very different and yield temperatures nearly 10 degrees colder than the same values from other areas.
Now you might think that to calculate temperatures for a period when seawaters were supposedly much warmer and saltier than now, you should use calibration values from the most similar existing area, i e the Red Sea.
If so you don’t think like a climate scientist.
Note that other proxies (oxygen isotopes, Mg/Ca, alkenone) don’t yield nearly as high temperatures.

Felix

Javier,
Mid-Cretaceous warmth and equability (little difference in temperature between the equator and poles) were indeed different from our climate system. Active seafloor spreading and continental rifting probably played a role, as would too have the shallow, epicontinental seas, such as covered so much of North America.
http://www.scotese.com/images/094.jpg

Felix

tty May 10, 2018 at 1:47 pm
Shortage of comparable samples today is a problem, to be sure. But not insuperable.
TEX86 found 36 degrees C.

tty

The oceans were very different in the Cretaceous. Today the deep water in the oceans comes from the arctic and antarctic where cold, salty and well-oxygenated water sinks, because it is the densest water anywhere in the ocean.
During the Cretaceous (and up through the Eocene) the densest water originated in the tropical Tethys sea, it was warm, very salty and oxygen-poor. In fact so oxygen-poor that the deep ocean sometimes became anoxic. The deep thermohaline circulation was very sluggish compared to now.
So oceans and ocean currents were very different then.

tty

“TEX86 found 36 degrees C.”
Not if you calibrate according to Red Sea values.

tty

Cited from the link above (my italics):
“Regardless of the choice of TEX86-SST calibration, application of the TEX86 proxy in the Cretaceous Period, where TEX86 values are frequently high (> 0.8), requires extrapolation of TEX86-SST calibrations
above the upper limit of the modern range reflected in the core-top datasets, ~0.72 (excluding data from the Red Sea; Kim et al., 2008; Kim et al., 2010).

Gary Pearse

Felix and others, It rained plenty to water all those lush Cretaceous plants so I believe there were ample aerosols to nucleate water drops. The mechanism that limits SST in the open oceans to 31C operated, period! If you have to change the physics to make the scenario you have wrought work, then (hint, hint) your scenario is wrong.

Gary Pearse

So it never rained in southern Shropshire.

Felix

Tty,
The authors cite reasons for excluding the Red Sea, although you might not concur.
Gary,
Much of the Mesozoic world was surprisingly dry, rather than lush forest. A lot of water obviously evaporated from the hot seas, but many continental interiors were open country, with conifers. Flowering plants didn’t become common until the Cretaceous.
http://ichef.bbci.co.uk/naturelibrary/images/ic/credit/640×395/s/sa/sauropoda/sauropoda_1.jpg
You don’t have to change physics to heat SST above 30 degrees C, just the tectonic arrangement.

Wim Röst

Javier, May 10, 2018 at 1:10 pm: “But their model is busted. Sea surface temperature doesn’t get above 30°C. Near that temperature deep convection prevents it from warming. It shows models can’t be trusted.”
WR: Javier is right. It is all about ‘interpretations’ of the proxies. See:
“Recent incubation (14) and core-top (15) studies resulted in a new calibration for TEX86 that is linear up to 40°C, which raises interpreted peak tropical SST by ∼5°C from those originally published using TEX86 (9). Thus, a newer interpretation (see supporting online material) for the warmest Eocene suggests tropical SSTs in the 35° to 40°C range, not the 33° to 28°C range published in 2007 (9), or the 25° to 30°C range as thought a decade ago (3), or the 20° to 25°C range accepted two decades ago (2).”
Source: Huber, M., A hotter Greenhouse? Science, 321, 353-354, doi: 10.1126/science.1161170, 2008

Smart Rock

Doesn’t have to be all the ocean, just the shallow seas where carbonate sedimentation took place.
This shows present (today) SST above 30° in the eastern Pacific, a small area in the eastern Atlantic and lots of the Indian Ocean and in the Indonesian archipelago
https://earth.nullschool.net/#current/ocean/surface/currents/overlay=sea_surface_temp/winkel3/loc=55.589,5.016

Felix

We know that it was warm enough in Cretaceous seas for giant, cold-blooded marine reptiles to survive and thrive. The cooler later Cretaceous might have helped kill off the ichthyosaurs, to be replaced by the enormous marine lizard mosasaurs, which evolved remarkably rapidly.

tty

If the Ichthyosaurs were poikilothermic, which is not really known. Oxygen isotope studies of teeth suggest that Ichthyosaurs and Plesiosaur body temperatures were fairly constant.
The Mosasaurs probably were poikilothermic though, since they are very closely related to varanid lizards.

Gary Pearse

Felix, I believe the once coldblooded dinosaurs (when I studied paleontology 60yrs ago) are more recently believed to be warmblooded – taking wing as birds in the evolutionary chain. Many appear to have had feathers in the Cretaceous.

Felix

Gary,
Dinosaurs had a form of warm-bloodedness, but the marine reptiles–ichthyosaurs, plesiosaurs and mosasaurs–were cold-blooded. The mosasaurs were even lizards, hence lepidosaurs, from the opposite side of the reptiles from the archosaurs, ie crocs (which have four-chambered hearts but with a hole to downrate them) and birds.

Felix

PS: Feathers predate the Cretaceous, as evinced by Archaeopteryx and more recent Jurassic finds. It’s likely that all coelurosaurs had some form of feathers, and possibly all theropods or even dinosaurs.
In any case, the giant marine reptiles are far removed from dinosaurs. Mosasaurs were lizards related to snakes. The phylogenetic position of ichthyosaurs and plesiosaurs is somewhat controversial, but the latter are possibly related to turtles.

Alan Mcintire
Felix

OK. They also gave live birth.
So, since 2010, the “consensus” has changed. Good for paleontological and biological science.
The marine reptiles were thought to be cold-blooded because their relatives are, and it was presumed that, like them, they had three chambered hearts. Today’s sea turtles and sea snakes are cold-blooded. Crocs are, as noted four chamber hearted animals downrated to resemble three chambers.
How you get endothermy with three chambered hearts I don’t know. But the isotope studies do at least suggest warm bloodedness of some kind.

Don K

“How you get endothermy with three chambered hearts I don’t know. But the isotope studies do at least suggest warm bloodedness of some kind.”
At least two groups of fish — the lamnid sharks and the scombrids — have managed to evolve some amount of endothermy with two chambered hearts. For that matter some insects that don’t have hearts at all warm themselves by “shivering” — does that count as endothermy?

Felix

Don K May 11, 2018 at 8:34 am
I guess it’s a definitional issue.
The fact is that no existing non-archosaurian reptile is endothermic by any definition, which is why it used to be thought that the large marine reptiles were the same.

Referring to the Cambrian as a ‘greenhouse’ period must be the nod to the pal reviewers. There are plenty of reasons other than the GHG effect that could cause a warmer climate, or the appearance of one.
For example, where any piece of land or ocean floor was 450 million years ago is not known with very high precision. Even the Pangea super continent hadn’t formed yet. How the distribution of land and water affecting global circulation patterns changes over millions of years is a more likely culprit.
We have little long term information on solar variability or its maximum extents. Proxies aren’t that precise or reliable. We only have objective data for a few decades and limited subjective data going back a few centuries.
It’s difficult to project orbital variability that far back as there are many higher order effects on the orbit and axis that we don’t know how to model and the resulting error increases the further back in time you project.

Most like it hot with lots of CO2, except Alarmists.

tty

What I can’t understand is how they link this warm interval to “the Cambrian Explosion”. Their data are from the very end of the Early Cambrian c. 510 myr ago while the “Cambrian Explosion” happened in the earliest Cambrian 530-540 milllion years ago. And there is strong evidence for at least local glaciation in the Earliest Cambrian:
https://www.academia.edu/1773700/First_evidence_for_Cambrian_glaciation_provided_by_sections_in_Avalonian_New_Brunswick_and_Ireland_Additional_data_for_Avalon_Gondwana_separation_by_the_earliest_Palaeozoic
This makes about as much sense as linking the origin of the Hominoidea (the Great Apes) in Africa back in the Miocene to the growth of the Laurentide icecap in the Pleistocene.

Felix

Thanks for the link, which includes study of the Avalon region, so important a source of Ediacaran fauna.
As noted above, early in the Cambrian, the chill was still on from the frosty Cryogenian and nippy Edacaran Periods.

Don K

I’m guessing, but I don’t think this press release is the work of the scientists who wrote the paper. For some reason, convention dictates that scientists are assumed to be incapable of communicating with ordinary mortals. An intermediary is therefore invoked to translate scientist-speak into English. The fact that the results are oftem dreadful doesn’t seem to bother anyone except the actual scientists. And who cares what they think?
I doubt that the paleontologists being interpreted here thought that warming triggered the Cambrian Explosion.
And yes, the Cambrian Explosion which presumably required tens of millions of years, must have taken place prior to the depositation of the Maotianshan shales in China around 522ma. Tangentially, I don’t have all that much faith in Cambrian “dating” and I don’t think anyone else should either. IIRC the date for the Burgess Shale drifted about 10 million years earlier in the decades after Gould published “Wonderful Life.”

No. The Cambrian explosion started ~520-510 mya with evolution of the ‘eye’. See long comment below. Read Gould’s Wonderful Life.

Felix

The so-called “explosion” started at the beginning of the Cambrian and lasted some 20 to 25 million years, ie from ~541 to 521 or 516 Ma, so overlapping with your estimate.
Gould was wrong, as noted elsewhere. He tried to make the facts fit his phony, Marxist theory.

Don K

Rud. My copy of Wonderful Life went somewhere three or for moves ago, but I’m quite certain that the dates Gould used are no longer operative. Current “wisdom” puts the MIddle Cambrian at 509ma to 497ma and the Burgess Shale is solidly Middle Cambrian despite sharing many elements with the older Maotianshan fauna. Problem is that there are few radiometrically datable beds in the Cambrian sequences that also contain fossils, so dating is not as easy as one might hope..
Redlichid trilobites are abundant throughout much of the Lower Cambrian. They had rather conspicuous eyes. There is lots of uncertainty about which is the oldest and when it lived. One candidate is Fallotopsis which might have been around as early as 540ma.
OTOH, everyone has their own dates for the Cambrian, so I suppose if you want to stick with yours, that’s maybe OK.

Felix

Don,
Regardless of the absolute dates, hard body parts, generally larger size (although there were big multicellular organisms and some biomineralization in the Ediacaran) and sensors such as eyes show up at or near the beginning of the Cambrian.
Unfortunately the reference ichnofossil marking the base of the Cambrian also appears to have existed in the Ediacaran. Or something very similar.

Felix

Yet again, my reply didn’t post.
Don’t know why.
Wordpress is censoring what seem innocuous responses.

Don K

“Regardless of the absolute dates, hard body parts, generally larger size (although there were big multicellular organisms and some biomineralization in the Ediacaran) and sensors such as eyes show up at or near the beginning of the Cambrian.”
I agree. Problem is that sometime (probably) before 540ma, multicellular life somehow diversified into quite comples and elaborate lifeforms — arthropods, brachiopods, mollusks, echinoderms, chordates, hemichordates, archeocyathids, etc,etc, etc. And it did so leaving few if any clues as to how that happened. The Vendian faunas don’t look like precursors. And the rest of the stuff in Ediacarian beds is quite interesting. But it doesn’t look much like primitive versions of Cambrian lifeforms — although some of it probably is exactly that.
“Unfortunately the reference ichnofossil marking the base of the Cambrian also appears to have existed in the Ediacaran. Or something very similar.”
You work with what you’ve got. I’m not sure that the date correlations between the various Cambrian landmasses are all that good, but without good radiometric dates and without universally distributed macrofossils, there’s bound to be a lot of guesswork.

tty

“Wonderful Life” is very dated. And eyes are older than that. The same gene regulates eye development in chordates and arthropods which is very strong evidence that the common ancestor had at least rudimentary eyes.
Also both the Sirius Passet and Chengjiang faunas are older (late Atdabanian) than the supposed date of the “explosion”. Remember that when Gould wrote “Wonderful life” the Middle Cambrian Burgess fauna was the only known Cambrian Konservastlagerstätte. Now there are many, including several from the Early Cambrian

Felix

Don K May 11, 2018 at 12:44 am
IMO the Ediacaran ancestors of the phyla which first show up in the Cambrian were too small and soft-bodied to fossilize and also of course lacked some of the defining traits of the crown groups. But agree that some Vendian impressions are likely ancestral to Cambrian phyla.
Please correct me if wrong, but haven’t impressions of small, less shelly trilobites been found in Cambrian Konservat-Lagerstätten?
Tty,
Agree on all points. iMO Gould is not only outdated, but his conclusions were wrong even given the knowledge of the 1980s. (The German plural is as above.)

How can there have been limestone in a “greenhouse” Cambrian? Wouldn’t it have all dissolved in an ocean of vinegar with atmospheric CO2 at 10-50,000 ppm?

Felix

Cambrian CO2 probably ranged from ~7000 to 4500 ppm.

Don K

There are plenty of Cambrian limestones scattered about the planet. Maybe the CO2 level was a bit more moderate than 10-50000 ppm.. AFAICS, paleo CO2 estimates are SWAGs with the emphasis on the WILD element of the guess. Or maybe pH isn’t all that important. Heck, maybe we aren’t all going to die if (when) we don’t change our evil ways.

Jacob Frank

Settled science has the fact that it has never evah been hotter than now. Soon a lawsuit will be filed against this denier climate model until it stops denying scientific facts.

The Cambrian explosion was clearly ecoterrorism, giving confirmation – if any were needed – of how bad CO2 is.

John Bell

What i want to go back and see is the coal beds forming, fascinating!

james feltus

“Data from the tiny fossil shells, and data from new climate model runs, show that high latitude (~65 °S) sea temperatures were in excess of 20 °C.”
“Scientists made the discovery while looking for clues in tiny fossil shells in blocks of Shropshire limestone…”
I think you meant to write “~65 N”.

Felix

Nope. They meant high South paleolatitude. The abstract:
The oceans of the early Cambrian (~541 to 509 million years ago) were the setting for a marked diversification of animal life. However, sea temperatures—a key component of the early Cambrian marine environment—remain unconstrained, in part because of a substantial time gap in the stable oxygen isotope (δ18O) record before the evolution of euconodonts. We show that previously overlooked sources of fossil biogenic phosphate have the potential to fill this gap. Pristine phosphatic microfossils from the Comley Limestones, UK, yield a robust δ18O signature, suggesting sea surface temperatures of 20° to 25°C at high southern paleolatitudes (~65°S to 70°S) between ~514 and 509 million years ago. These sea temperatures are consistent with the distribution of coeval evaporite and calcrete deposits, peak continental weathering rates, and also our climate model simulations for this interval. Our results support an early Cambrian greenhouse climate comparable to those of the late Mesozoic and early Cenozoic, offering a framework for exploring the interplay between biotic and environmental controls on Cambrian animal diversification.

Gary Pearse

Shropshire would appear to have been in an equatorial position during the Cambrian (Europe located along the northern shore area of Gondwanaland. Also, the oxygen isotope ratios give the temperature – no climate models needed.Surely it can’t be that the scientists of Leicester U are unaware of where the samples came from relative to the equator? The temp results (which were already known before this “new” discovery) seem to be much like today’s SST, which in the open ocean has a limiting upper temp of 31C. I’ve noticed that all the “new discoveries” of the past 20yrs all add a spurious bit, in this case the unnecessary “climate model” to make it look new. It is the “curtain” behind which the old discovery is hidden.
http://www.ucmp.berkeley.edu/cambrian/cambtect.html

Went and read the paper because of an enduring interest in the Cambrian explosion. The earliest complex multicellular organisms are the Ediacaran fauna, named after Ediacara Hills, Aus and now being found everywhere except Antarctica. These were pure soft bodies, typically only coarsely preserved in fine sandstones from river delta sandbars, so shallow water. Two basic forms, tubes and fronds. Important because they could only evolve when ‘the great rusting’ was over and atmospheric oxygen could finally build to sufficient concentrations. Roughly 600-540mya. Then came the development of early hard exoskeletons, the so called Small Shelly Fauna (SSF), named in 1972. A bit of a misnomer, because although small shelly fauna like tiny snail like mollusks evolved, many of the SSF bits were later identified as fragments of larger newly ‘shelly’ organisms like sponges and brachiopods. Three shelly chemical types: silica, calcium phosphate, calcium carbonate. Roughly 550-520mya. Then came the early Cambrian and the Cambrian explosion (I have a treasured personally signed copy of Stephen J. Gould’s 1989 book Wonderful Life about the seminal Burgess Shale dated 508mya.) Clear arms race between predators and prey set off by fossil evidence for the evolution of the eye(s)—as there are three distinct eye types, compound (trilobites, insects), sensors in front of supporting membrane and capillaries (cephalopods) and sensors behind supporting membrane (all vertebrates, and why humans develop macular degeneration). ‘Intelligent design’ apparently favored squids (see the long example in my ebook The Arts of Truth, and footnoted references therein).
It has been long known that the Burgess Shale was a shallow near equatorial (at the time) warm water very bio productive ‘reef’ environment subject to occaisional reef face slumping into deeper colder anoxic water (anoxic because of surface productivity, no different than oil and gas deposits, and hence the remarkable preservation of both hard and soft Burgess Shale tissues). Of course warm, since near the equator.
The new paper uses early Cambrian (contemporaneous to Burgess Shale) SSF calcium phosphate d18O ratios to determine near sea surface temps at roughly 65S (the then modeled location of these UK limestones, a fairly high non equatorial latitude). Used weak acid to dissolve them out of calcium carbonate matrix, then a set of exquisitely precise d18O ratios with standard long standing d18O/ near SST paleoproxy calibrations. The model stuff is incidental to the observational/lab science, and partly just to backtrack plate tectonics to estimate the originating latitude. Fairly well accepted geological stuff.
IMO a nice contribution to science.
A great WUWT post.

Samuel C Cogar

ristvan – May 10, 2018 at 3:11 pm

Then came the early Cambrian and the Cambrian explosion

The Cambrian explosion could not have been the result of “descent with modifications” via gene mutations occurring from parent to offspring.
Said “explosion” of so many different phyla of animals had to have been primarily “driven” by Horizontal Gene Transfers rather than random mutations in/of “line-of-descent” reproduction.
If not Horizontal Gene Transfers in its “origin history”, how else could an animal such as the Platypus evolved, ……. surely not by random gene mutations.

Felix

Samuel,
The first appearance of many phyla during the Cambrian could not have resulted from HGT.
To support this baseless conjecture, you’d need to show precisely which genes transferred from which original to which receiving organisms led to each phylum.
Please state what gene transfers produced our phylum, Chordata. How about the diverse Phylum Arthropoda? Mollusca? Any such transfers producing any phylum at all? Thanks!
OTOH, there are good candidates for ancestors to these phyla in the final period of the Precambrian, a conclusion supported not just by rocks but molecular clocks, genetics, embryology, anatomy and every other line of evidence.

Felix

My reply has yet again gone missing. Hope it shows up.
Won’t risk duplication by reposting it.

Felix

Most certainly the platypus and every other mammal, whether monotreme, marsupial or placental, and all other species of microbes, fungi, plants and animals on earth evolved thanks to mutations in their genetic codes.

Samuel C Cogar

Felix – May 11, 2018 at 3:56 pm

Samuel,
The first appearance of many phyla during the Cambrian could not have resulted from HGT.
To support this baseless conjecture, you’d need to show precisely which genes transferred from which original to which receiving organisms led to each phylum.

Felix, you shur are “hung up” pretty tight on that “baseless conjecture” thingy, …… now aren’t ya?
Is that brain-mind “hang up” because of your adolescent inexperience, your misnurturing, your miseducation or your being “brainwashed” by your PC pseudo-science teaching mentors?
Felix, I don’t think that you are simply trying to be “silly”, …… I actually think you are “silly” due to your silly “PC neo-science” nurturing.
Why in gawds name would you “demand” that I ….. “show precisely which genes transferred that led to each newly evolved phylum”, ……… when neither you, Felix, ….. or anyone you know, ….. or anyone you ever heard of, …….. is capable of precisely showing which genes were transferred from one (1) or more members, …. or descendent member(s), ….. of the genus Homo ……. of the Family of Great Apes that led to the evolution of Homo sapiens sapiens (modern humans).
Here Felix, chew on this one in your spare time, and then explain how that “species explosion” occurred.

More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. https://en.wikipedia.org/wiki/Extinction

Samuel C Cogar

Felix – May 11, 2018 at 3:56 pm

Samuel,
The first appearance of many phyla during the Cambrian could not have resulted from HGT.
To support this baseless conjecture, you’d need to show precisely which genes transferred from which original to which receiving organisms led to each phylum.

Felix, you shur are “fixated” pretty tight on that “baseless conjecture” thingy, …… now aren’t ya?
Is that mental “fixation” the result of inexperience, misnurturing, miseducation or your PC pseudo-science teaching mentors?
Felix, why would you “demand” that I ….. “show precisely which genes transferred that led to each newly evolved phylum”, ……… when neither you, Felix, ….. or anyone you know, ….. or anyone you ever heard of, …….. is capable of precisely showing which genes were transferred from one (1) or more members, …. or descendent member(s), ….. of the Family of Great Apes that led to the evolution of Homo sapiens sapiens (modern humans).
Here Felix, chew on this one in your spare time, and then explain how that “species explosion” occurred.

More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. https://en.wikipedia.org/wiki/Extinction

otsar

Does anyone know the atmospheric pressures and nitrogen levels during the Cretaceous?

Felix

Analysis of air samples from the latest Cretaceous shows that O2 content was close to the fire-dangerous levels of the Carboniferous, ie ~35%. So atmospheric pressure would have been a little higher. N2 was naturally a bit lower as a percent, but in absolute terms was about the same:
https://geology.com/usgs/amber/

Don K

“Analysis of air samples from the latest Cretaceous shows that O2 content was close to the fire-dangerous levels of the Carboniferous, ie ~35%.”
I’m sure they do show that. But where did the 15% Oxygen that was there in the Cretaceous and isn’t there now go? Atmospheric Carbon seems to have been less than 1% (that’d be 10,000 ppm, right?) . Is that enough to fix all that Oxygen? Where are the kilometers thick(?) beds of carbonate or other oxide where that Oxygen is sequestered?
I’m a bit more skeptical of ALL paleo-proxies for everything than others are. Perhaps I should be more accepting.

Felix

Don,
If this USGS graph sowing a pretty abrupt drop in O2 be in the ball park, then it appears that fires from the Yucatan impact might have contributed to the rapid decline. Note that other proxies besides amber show only 25% O2 at Cretaceous peaks. Fire was however important in Cretaceous climate and biology, to include possibly the rapid evolution of flowering plants, many of which were weedy, ie colonizers of disturbed systems. There is a lot of Cretaceous charcoal.comment image
The late Cretaceous and early Paleogene (Paleocene Epoch) did see a lot of carbonate laid down, too.

My numbers agree with this analysis, about +10C.
But the Edicaran life forms started about 600 Mya, 60 million years earlier, when temperatures were close to today’s.

Wim Röst

Sorry Bill, I don’t understand what you are reacting on in your comment: “this analysis, about + 10C”
(As you know I am very interested in well calibrated (!) deep sea temperatures. And most of the SST numbers of fig. 4 of the study itself – 30C to 40+C – seem way too high. Above, Javier already commented about that)

Greytide

If the seas where so much warmer, presumably at a time when corals where exploding in the oceans, why do we get the “Warmer seas will kill all the corals” headlines.? I have never understood the claims that it is raised water temp that kills corals as the most rapid growth I have seen has been in the shallower/warmer waters around the reef. Corals seem to have survived a greatly changed temperature environment over their existence so I find it hard to believe that a small SST change will kill them off. I believe the temperature is a red herring and there is something else going on here.

All the evidence that is interpreted as “millions of years” was laid down in stratified layers of mud that turned to rock– that, all over the world, showing no evidence of erosion between the layers which would be plain to see if they were laid down over time. All over the earth are millions of dead things trapped in mud that was being carried in currents and stratified according to its weight, just like happens any time mud is suspended in fast moving water, and then settles. The ancient document that describes this world wide flood, says that eight people were preserved in a boat that they had built when God told them to prepare for the disaster that was coming. There are many people who have never given the document, or the evidence, any consideration, because when the original fraud was conducted, the media shut out those who said, “quit doing circular thinking–you can’t claim an age for the rock using the layers as your guide, and then claim that the fossils are a certain age because of the rock they are trapped in.” All of the “carbon dating” gives wide ranges of ages to rocks of known short age, which have been sent for “carbon dating” by skeptical scientists who have suspected that carbon dating is a useless hoax. The “cambrian explosion” is just all the animals that got caught in the flood and were rapidly entombed–some even while giving birth, or eating another animal. Some are in positions where they would have to hang in the air for millions of years, in excellent shape, even having all their skin, eyes, etc while the layers built up around them. The scenario called
“millions of years” without any explanation, just doesn’t work. And, yes, it was uniformly warm before the flood. The document which has been preserved all through the years, and is now part of the larger book known as The Bible, says that there was some kind of “covering” over the earth, that was destroyed in the flood–leaving the earth subject to wide changes of temperature.

WBWilson

Holy Cow. I am speechless.):(

Felix

Sorry, but it’s obvious that you’ve never studied geology or actually even looked at rock layers and into them. Everything you assert is easily demonstrated false.
Far from showing no erosion, many layers are totally missing in places. Marine and terrestrial layers alternate. Animal fossils don’t sort by size, but by age.
The Bible is wrong about every aspect of every natural science on which it comments. Even Augustine of Hippo and John Calvin knew that its descriptions of the physical world weren’t literally true. In this, the most important Catholic and Protestant theologians were correct.
The way to understand God’s Work is by observing it, not by reading His alleged Word.