Greenhouse ‘time machine’ sheds light on corn domestication

teosinte size

A grass called teosinte is thought to be the ancestor of corn, but it doesn’t look much like corn at all. Smithsonian scientists were surprised to find that teosinte planted in growth chambers under climate conditions that simulate the environment 10-12,000 years ago looks more like corn. This may help to explain why early farmers chose to cultivate teosinte and lends support to the idea that teosinte was domesticated to become one of the most important staple crops in the world.

By simulating the environment when corn was first exploited by people and then domesticated, Smithsonian scientists discovered that corn’s ancestor, a wild grass called teosinte, may have looked very different then than it does today. The fact that it looks more like corn under these conditions may help to explain how teosinte came to be selected by early farmers who turned it into one of the most important staple crops in the world.

The vegetative and flowering structures of modern teosinte are very different from those of corn. These and other differences led to a century-long dispute as to whether teosinte could really be the ancestor of corn.

“We grew teosinte in the conditions that it encountered 10,000 years ago during the early Holocene period: temperatures 2–3 degrees Celsius cooler than today’s with atmospheric carbon dioxide levels at around 260 parts per million,” said Dolores Piperno, senior scientist and curator of archaeobotany and South American archaeology at the Smithsonian’s National Museum of Natural History and the Smithsonian Tropical Research Institute, who led the project. “Intriguingly, the teosinte plants grown under past conditions exhibit characteristics more like corn: a single main stem topped by a single tassel, a few, very short branches tipped by female ears and synchronous seed maturation.

After the Industrial Revolution, carbon dioxide rose to today’s 405 parts per million, the level in the control chamber where teosinte plants look like plants in the wild today—tall, with many long branches tipped by tassels and seed maturation taking place over a period of a few months. Co-author Klaus Winter usually studies the effects of rising atmospheric carbon dioxide levels on tropical plants as a senior staff scientist at STRI. Piperno and Winter devised a scheme to essentially travel back in time by comparing plants grown in modern conditions with plants grown in the early Holocene chamber.

“Now it appears to be an open question when in the Holocene teosinte became the plant very distinctive from maize in vegetative architecture and inflorescence sexuality that we see today and use as the baseline for research on maize domestication,” said Piperno. “When humans first began to cultivate teosinte about 10,000 years ago, it was probably more maize-like—naturally exhibiting some characteristics previously thought to result from human selection and domestication. The environment may have played a significant, if serendipitous, role in the transition through inducing phenotypic plasticity that gave early farmers a head start.”

Phenotypic plasticity is an organism’s ability to change in response to the environment, causing genetically identical organisms to look very different when they live in different conditions. As they formulate a “new modern evolutionary synthesis,” in part with concepts that Darwin could not have known of, evolutionary biologists continue to debate the importance of the environment and plasticity on evolutionary change and the origins of the diverse forms of life on Earth today. However, new evidence shows that these environmental–phenotypic interactions are in a growing number of organisms. This is one of the first studies to examine the influence of these processes on plant domestication.

“Extending these concepts to domestication research allows anthropologists to become more fully engaged in modern evolutionary theory and practice,” Piperno said.

The Smithsonian Tropical Research Institute, headquartered in Panama City, Panama, is a unit of the Smithsonian Institution. The Institute furthers the understanding of tropical nature and its importance to human welfare, trains students to conduct research in the tropics and promotes conservation by increasing public awareness of the beauty and importance of tropical ecosystems. Website: www.stri.si.edu.

# # #

SI-25-2014

Piperno, D.R., et al., Teosinte before domestication: Experimental study of growth and phenotypic variability in Late Pleistocene and early Holocene environments. Quaternary International (2014). http://www.sciencedirect.com/science/article/pii/S104061821300983X

The PR is from The Smithsonian

I have to wonder though, where they get this info: “After the Industrial Revolution, carbon dioxide rose to today’s 405 parts per million”.

Last I checked, today, MLO was still below 400 ppm:

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52 thoughts on “Greenhouse ‘time machine’ sheds light on corn domestication

  1. These and other differences led to a century-long dispute as to whether teosinte could really be the ancestor of corn.

    The estimate of 260 ppm for 10,000 years ago isn’t much change to the 280 ppm of a century ago so the reference to 405 ppm (local estimate?) seems to be a mis-direction. Note the text claims the argument started an imprecise century ago.
    Another hypothesis is that there was a plant that mutated (an early GM candidate) and was selected because of its better traits. In botany, especially tree fruits, say apples, these new types are called sports.

  2. “We grew teosinte in the conditions that it encountered 10,000 years ago during the early Holocene period…:
    ————
    I hope nobody tries to make a joke about corn-holocene!


  3. Phenotypic plasticity is an organism’s ability to change in response to the environment, causing genetically identical organisms to look very different when they live in different conditions.

    So … what is the genetic similarity of corn to teosinte?

    .

  4. Perhaps temperature and CO2 levels are not dependent variables. That is to say, it seems possible that a Holocene Chamber with 260 ppm CO2 and no temperature adjustment would likely produce the same result.

    Although corn was first domesticated in Mesoamerica, 300 miles of travel in either polar direction would produce the same 2-3 degree C temperature change.

  5. The ability of a population to evolve is an evolved trait as is phenotype plasticity. It should be no surprise that they are related. BTW, the public school version of the theory of evolution is designed primarily as a mechanism to denigrate Christianity. It is about as close to the real thing as is the mischaracterization of Christian belief that public school teachers use in contrast.

    A populations evolutionary trajectory is in the direction that maximizes the ability of the population to produce offspring that live long enough to produce offspring. Therefore Dr. Flying Spaghetti Monster is a fraud.

  6. Have there been studies that show carbon dioxide concentrations in the atmosphere 10 thousand years ago in regions where teosinte grew? The 260 ppm is from polar ice core data. Last I heard, our ancestors weren’t doing much farming in Antarctica or Greenland back then.

  7. Interesting but not convincing, since early mesoAmericans lived in a variety of microclimates given the mountainous nature of the region, so temperature and CO2 need to be teased apart. But this is certainly an extreme example of the new concept of phenotypical plasticity (originating in what 20 years ago was though to be junk DNA, but which we know know at least partly controls gene expression). Another vivid example of the science is not settled…

  8. The devil is in the details. The exact quote was “Intriguingly, the teosinte plants grown under past conditions exhibit characteristics more like corn: a single main stem topped by a single tassel, a few, very short branches tipped by female ears and synchronous seed maturation”.

    This means that all of those things must be present. This being the first time I was ever interested in this plant, I searched the net for real-world pictures, not the wikipedia pictures that are everywhere. If you look at Teosinte grown in Colorado (slightly colder, slightly less CO2 because of altitude), you get a single main stem, very few short branches with female ears, but multiple tassels. See http://keen101.wordpress.com/2011/10/21/growing-prehistoric-corn-teosinte/ for examples. He has a photobucket list of photos.

    That looks enough like corn to get a meager harvest, but it doesn’t have a single tassel and who knows about sychronous maturation. I’m just saying that if these plants are grown in cold mountain conditions today, shouldn’t that also simulate conditions 10k yrs ago? Are there naturally occuring growing conditions today that give teosinte a single tassel? I’m betting the Smithsonian didn’t ask that question with too much enthusiasm.

    As an interesting discovery because of this story, I found that there are a few people on the net documenting their gardens of teosinte crossing with corn and indian corn. Who knew that was a hobby?

    • JDN says:

      I found that there are a few people on the net documenting their gardens of teosinte crossing with corn and indian corn. Who knew that was a hobby?

      Every possible occupation is certain to be exercised by somebody as a hobby. In agricultural selection, crossing a promising cultivar with a wild type to kick it out of a dead end or an undesired local optimum is almost a knee-jerk reaction. Got larger fruits? Good. Roots not viable in the field? Need another cross.

  9. I’ve been involved with the preservation of a specific Native American corn variety for years. It is not unusual for occasional plants to revert to some ancient variety which bears little resemblance to modern “corn”.

  10. The paper doesn’t make sense. About 10,000 years ago, at the beginnning of the Holocene, the temperatures were higher, not lower than todays. It be interesting to see the behavior of teosinte under actual holocene conditions.

  11. Maybe it’s just my memory playing tricks on me, but I’d swear that I’ve seen plants resembling teosinte growing in fallow cornfields. Could it be that a seed from a modern hybrid plant would revert to phenotypes more closely resembling teosinte if it lies in the ground all winter and is allowed to sprout and grow in an uncrowded environment?

  12. docstephens says:
    February 3, 2014 at 9:58 am

    Have there been studies that show carbon dioxide concentrations in the atmosphere 10 thousand years ago in regions where teosinte grew? The 260 ppm is from polar ice core data.
    ———————

    Tes, studies of fossil plant stomata, … to wit:

    Data from various stomata studies (ref. 10-20) show CO2 concentrations over the last 11,000 years varied between 260 and 340 ppm (average: 305 ppm). In contrast, the Dome C ice core record shows no significant variability and considerably lower overall CO2 levels (average: 270 ppm).http://www.geocraft.com/WVFossils/stomata.html

  13. 10,00 years ago it was warmer than today with an attendant CO2 spike that would have been much higher than 400ppm. See what those conditions do for teosinte.

  14. _Jim says: @ February 3, 2014 at 9:37 am

    So … what is the genetic similarity of corn to teosinte?
    >>>>>>>>>>>>>>
    That was my first thought.

    If they can figure out how many descendants Genghis Khan has and 1 to 4% of non-African modern human DNA is shared with Neanderthals, you would think they could figure out if teosinte is an ancestor to corn and what the genetic differences are.

    I am not up on genetics but if I recall what I read correctly, the number of mutations can give a pretty good idea of when a branching occurred.

    modern day DNA studies have indicated that a specific Y-chromosomal lineage with patterns suggesting that it originated from Mongolia about 1000 years ago, and this marker can now be found in 8% of the men in a large region of Asia and parts of Europe. It is proposed that this lineage is carried by Genghis Khan and is carried by male line descendants of Genghis Khan.

    http://www.dnaancestryproject.com/ydna_intro_famous.php?id=genghiskhan

  15. LeeHarvey says: @ February 3, 2014 at 11:00 am

    Maybe it’s just my memory playing tricks on me, but I’d swear that I’ve seen plants resembling teosinte growing in fallow cornfields….
    >>>>>>>>>>>>>>>
    The pure bred parents of modern hybrid seed corn are pretty anemic looking scraggly messes you would have a hard time identifying as modern corn. You are probably seeing reversion towards the pure breds. (Ex husband worked for a seed corn company during Vietnam era)

  16. @Gene Selkov –

    Nope… never been south of Monterrey, and I don’t ever recall seeing a cornfield up close in Mexico. I was thinking specifically of fields in Iowa.

    @Gail Combs –

    I think you may have pegged what I was seeing.

  17. The more problematic issue is 10ky New World agriculture–I think that’s still a minority position, about 4ky too early by the majority, especially for corn. –AGF

  18. Not only did they get the current ppm levels wrong, but they seem to be unaware that levels of CO2 didn’t start to take off until about mid century last century, not at the start of the industrial revolution.

  19. agfosterjr said @ February 3, 2014 at 2:32 pm

    The more problematic issue is 10ky New World agriculture–I think that’s still a minority position, about 4ky too early by the majority, especially for corn. –AGF

    The paper I referenced above says:

    With this set of microsatellites, ssp. parviglumis and Mexican maize have a divergence time of 9,188 B.P. (95% confidence limits of 5,689–13,093 B.P.).

    Close enough to 10kya. The continuation of Mexican maize required human intervention. Maize doesn’t self-sow.

  20. American corn/maize is a genetic expression that must be selected for continually. While it does self sow or regrow from seed that falls to the ground, the genetic expression drifts do to stress from environmental causes. Modern varieties are mostly hybrid and cannot accurately recreate themselves. Old straight bred lines are somewhat flaky and still must be rouged of undesirables to get the best expression in the next generation of the characteristic desired. Without constant selection corn/maize will revert to grass after a number of generations. On the other hand its’ very rich double dose of genes gives it an extreme range of possibilities for GMO design. Corn/maize is grown in every environment that can be farmed, from Alaska to Chile. Not bad for a subtropical grass.
    This guy can’t even get the CO2 content of the atmosphere correct. I’m not sure I would give too much credence to the rest of his assertions. ;-) pg

  21. Whether those researchers are right or wrong and I suspect they are partly wrong in their conclusions, spare a thought for those guys and gals, those unrecognised researchers who have tramped and travelled endless kilometres over the past 6 decades in some of the most inhospitable regions on earth to try and find those often quite small natural remnants of the old and original plant species that are the very foundation today of mankind’s and his domesticated animal’s food supplies.
    Spare a thought for the laboratory staffs who both analyse both the potential food characteristics of those old species as well as the outcomes of their crosses that provide us with most of our major food supplies today,
    Spare a thought for the plant geneticists, few in number across the world, who put together the appropiate genes from a whole range of varieties and species to pass onto the plant breeders.

    And spare a thought for the plant breeders, those highly dedicated but globally small in number, group of men and women who when they begin their careers after gaining employment as a plant breeder may not see any commercially acceptable outcomes for their plant breeding efforts for perhaps some dozen or often more years.
    It takes ten to fifteen years to produce a new and improved variety of wheat and much, much longer than that, a couple of decades for improved fruit trees and many other similar fruiting food plant species.

    Without those plant breeding researchers, most of them highly dedicated, they have to be dedicated as they are usually paid a lot less for their essential to humanity’s food plant breeding efforts than most so called climate scientists, a large percentage of mankind’s numbers, possibly as many as three quarters of mankind’s present day numbers would starve or be killed in the ensuring breakdown of society if a major global food shortage developed.

    It can still happen as with the UG99 rust of a few years ago which wiped out wheat varieties in
    Africa and the middle east that were not resistant to that strain of rust which very few of all currently grown varieties of wheat are.
    The geneticists and breeders moved fast in an international effort to find resistance to UG99 in other varieties and in those ancient plant species and to transfer that resistance to new varieties to counter the UG99 rust fungus.

    Each and every one of those plant food researchers and plant breeders and the work they do, the real actual results of which each of us can eat our fill of food each day, every day, and that for all 7 billions of our numbers, are worth some many hundreds of so called climate scientists in their importance to mankind and mankind’s future.

    Climate scientists have produced nothing of lasting or even short term value to humanity.
    Plant breeders feed the world, all seven billions of us and an even larger number of the animals upon which humanity depends for food, transport and pleasure.

    Without those food researchers and plant breeders, most of future humanity will eventually starve.
    Without today’s version of climate scientists the world would be much richer, far less traumatized by groundless and baseless climate scientist’s deliberately generated fears and far more socially cohesive.
    And science itself would still be a profession that would still be admired and respected.

  22. “The paper I referenced above says:

    With this set of microsatellites, ssp. parviglumis and Mexican maize have a divergence time of 9,188 B.P. (95% confidence limits of 5,689–13,093 B.P.).”

    If this is true it will indeed push new world domestication back by a factor of 2. Archaeologists debate whether humans had even made it across the Bering land bridge before 12 kya.

    If “domestication” can be construed as picking the fattest ears and heaving them in the midden where they would thrive, I would believe.

  23. Another reference:

    http://cals.arizona.edu/fps/sites/cals.arizona.edu.fps/files/cotw/Sweet_Corn.pdf

    The cultivation of corn (maize) (zea mays) began over 8,000 years ago in Mesoamerica… humans have transformed corn into a plant that can no longer self-sow…

    I have grown sweet corn for over thirty years and have never had a problem sowing most home saved F1 hybrid seed (not supersweets). I have never seen self-sown sweet corn. The seed stays tightly attached to the cobs and has never shattered. My Googling for “self-sown maize” found the above.

  24. An easy experiment for high school students to test for their next Science Fair.
    Can they replicate the results?
    What if they change some parameters – say the same few degrees cooler and CO2 @ 400ppm?
    Tricky bits are what is the growing season for teosinte? How do you cool its environment by 2 – 3 degrees C yet keep the same day/night cycle? And so on. Like I say, a great science experiment!
    If I was in grade ten and looking for something to enter this would seem to be a winner!

  25. Doh!

    So, instead of spending millions of $ on growth chamber experiments purporting to look at the impact of high levels of atmospheric CO2 on plant growth, maybe we should stop wasting our time (and money) and look for the new super food plant by screening potential crop species at low CO2 levels? Who would have thought?

    And, corn, by the way, being a C4 is a super food crop compared to a lot of other species of food crops – uses less water per unit CO2 fixed and is able to utilize lower levels of atmospheric CO2.

    Just another example of how the warmistas are screwing the human race by diverting large amounts of funding toward supporting political policy rather than basic ideas and science.

  26. There is no guarantee that CO2 levels were 260ppmv back then. This figure is a guess from some climate model, ie. it was cold therefore CO2 levels had to be low. This does not follow ice core research which shows that the present increase of CO2 is likely due to the MWP not the paltry mass of CO2 we inject.
    The plant was more likely different because of the ice age that was then at its height.

  27. An interesting question regarding the evolution of teosinte into maize might be: were there any cultivation techniques that could bring about genetic modification without selection? The extent of the divergence from ancestor to descendant would seem to have left room for some sort of other treatment besides selection. This question is an important one from the standpoint of arguments against GMO crops. The fact is, every crop grown for human use has been genetically modified – the only question is how and when.

    This is also not merely an academic question, since objections to GMO have resulted in such atrocities as the destruction by Greenpeace of the experimental farm in the Philippines, where a variety of rice (“golden rice”) modified to provide vitamin A, as a preventative of childhood blindness, was under development. Golden rice promised to eliminate up to 500,000 cases annually of childhood blindness due to vitamin A deficiency in the countries where rice is the primary staple. (A notable example of anti-human, anti-environmental leftist superstition at work, so characteristic of Greenpeace today.)

  28. johnmarshall says:
    February 4, 2014 at 2:41 am
    “There is no guarantee that CO2 levels were 260ppmv back then. This figure is a guess from some climate model, ie. it was cold therefore CO2 levels had to be low. This does not follow ice core research which shows …….”
    …..and many similar comments like that
    ( I’m not picking on johnmarshall particularly)

    —–

    People speak so glibly about this CO2 level, or that CO2 level, as though it were a fixed thing that slowly is rising, and even accelerating rising over the last century or something, and that we Humans has caused this by our massive industrial activity.

    I say Pshaw !

    The reality is that CO2 does NOT stay in the atmosphere for thousands of years and varies a lot from place to place, from year to year, from season to season, from day to day, and from night to day. In fact CO2 concentrations change all the time and there is NO SUCH THING as “Average World CO2″. To claim that “Average World CO2″ has any relevant meaning is utter bunkum. The concept is completely meaningless, except in fatuous calculations, intended to baffle politicians, and deceive the taxpayer.

    See this image :
    Salt Lake City Atmospheric Carbon Dioxide Measurements
    Yearly

    You may see the CO2 baseline rising slightly, but the seasonal variation, regularly shows values of over 500 ppm in the Wintertime (low botanical absorption, trees not in leaf, few crops growing), whereas in the Summertime the CO2 can fall to below 390 ppm. Again if we look at the chart for Monthly Figure (last 28 days), we see that the CO2 is all over the place and varies from about 400 ppm to over 600 ppm, with no clear trend or pattern.
    Monthly

    See the full series at the University of Utah Website Linked to My Name

    • SLCO2 @ Utah says:

      The reality is that CO2 does NOT stay in the atmosphere for thousands of years and varies a lot from place to place, from year to year, from season to season, from day to day, and from night to day.

      Such considerations are enough to make the 260 ppm proposition look laughable. It starts looking downright stupid and worthy of contempt when you consider the scale of that variation. CO2 varies by an order of magnitude within the first couple metres above the ground, both spatially and temporally.

      It does not vary as much at higher altitudes, where seekers after certainty have fixated their attention, and its vertical gradient up to about 70 km is next to naught (which is a bit of a puzzle), but what does that have to do with corn?

      I can’t believe they haven’t heard of microclimatology.

  29. @ The Pompous Git

    Self sowing maize (corn) ….. and you sowing maize (corn) are two different processes.

    The individual seeds of corn do not fall off the corn cob onto the ground, thus it can not re-seed itself for the next years growth.

  30. @ Samuel C Cogar

    It was p. g. sharrow who claimed that maize self-sows, not me. “[I]ndividual seeds [that] fall off” is called shattering. I wrote: “The seed stays tightly attached to the cobs and has never shattered.”

  31. A cob of corn missed by the picker and then plowed under will in fact self-sow. It’s just that you get about a thousand plants trying to grow in the same place. They get about three inches tall and give up. The remarkable thing is that just before they drop over, if you listen carefully, you can hear them shouting “Make way – I am the co-recipient of the Nobel Peace Prize.”

  32. Corn is doomed. Starvation will spread due to Climastrology Change mixed with voodoo.

    HockeySchtick
    Tuesday, February 4, 2014
    New paper finds global warming could increase corn yields by 2 to 3 times per 1 degree C
    ———————————————–
    The impacts of long-term and year-to-year temperature change on corn yield in China

    Qi Zhang, Jiquan Zhang, Enliang Guo, Denghua Yan, Zhongyi Sun
    Abstract: Impacts of climate change on crop yield can be divided into long-term and year-to-year impacts. The goal of this study is to evaluate whether the long-term and the year-to-year impacts are different using historical datasets. Data on corn yields for 1961–2005 in Jilin and Anhui, located in northeastern and Mideastern China, respectively, are combined with datasets on temperature to build the statistical regression models for evaluation of the impacts of long-term and year-to-year temperature change on corn yield. Over half of the yield trends result from non-climatic factors, such as management and technology. Corn yields could increase threefold (measured by method 1) or twofold (method 2) as long-term temperature increased per degree centigrade. And agriculture in northeastern China has benefitted from climate warming. But the year-to-year temperature change could only result in 12 % yield increase, almost 20 times less than the impacts of long-term temperature change. We conclude that the impacts of long-term and year-to-year temperature change on crop yield are quite different. So, the models derived from year-to-year variations cannot be applied to assess the impacts of long-term climate change.

    http://link.springer.com/article/10.1007%2Fs00704-014-1093-3

    It really is much, much worse than I used to have thunk.

  33. ” and lends support to the idea that teosinte was domesticated to become one of the most important staple crops in the world.”
    “Extending these concepts to domestication research allows anthropologists to become more fully engaged in modern evolutionary theory and practice,” Piperno said.”

    I found these a bit odd. For some bizarre reason many in this field have been against the work of a women named Mary Eubanks. (she works a duke unniversity) She crossed bred tesosinte and a grass related to corn called gammagrass, and got what looks nearly identical to the earliest corns. which tells us the likely source of corn.

    What is even stranger about her work being ignored is she has shown that we can bring gene (even with conventional breeding) from many teosintes, grasses and related plants into corn. some of her earliest work had some rather extreme success through harsher then normal years in goergia.

    It is also a bit weird it is ignored since this would explain why most teosintes do not readily cross to corn(they do cross to gammagrass as does corn which is how you can transfer genes) If true and it really appears to be imo, then corn is both teosinte and gammagrass.

    not the best link on the topic but just so we are clear who I am talking about…

    http://www.eurekalert.org/pub_releases/2004-04/du-poc033004.php

  34. @Randy –
    Your comments re gramma grass and teosinte both ancestral to corn would suggest something different from the usual modification solely through selection – which may provide evidence of the antiquity of GMO techniques other than selection.

  35. …. horizontal gene transfer (HGT) between unrelated plant species is ubiquitous.

    Ah so, …. and me thinks the Cambrian Explosion is testimony to the fact that HGT occurs.
    Especially when one considers the potential fact that all DNA had to have been a much simpler form in that day and time.

  36. johnmarshall says:
    February 4, 2014 at 2:41 am

    There is no guarantee that CO2 levels were 260ppmv back then. This figure is a guess from some climate model, ie. it was cold therefore CO2 levels had to be low. This does not follow ice core research which shows that the present increase of CO2 is likely due to the MWP not the paltry mass of CO2 we inject.

    Nothing to do with climate models, but that is what is found in ice cores:

    The “end blade” of the CO2 hockeystick is not from the MWP, as the MWP-LIA difference is only ~6 ppmv:

    SLCO2 @ Utah says:
    February 4, 2014 at 11:06 am

    In fact CO2 concentrations change all the time and there is NO SUCH THING as “Average World CO2″

    If you look at the CO2 levels everywhere, there is very little variability (+/- 2% of full scale) in 95% of the atmosphere. That is all over the oceans (surface to 20 km height) and above a few hundred meters over land. The average of several ground level stations (not Mauna Loa) is defined as the “global” CO2 level.

    Most variability is in the first few meters up to a few hundred meters over land where a lot of fast sources and sinks are at work and wind/turbulence are not fast enough to mix it all with the rest of the atmosphere.
    Therefore I wonder how the researchers could know what the local CO2 levels were 10 kyear ago, as that strongly depends of the local circumstances like topography (more CO2 in valleys), under inversion, amount of decaying vegetation, temperature, sunlight,…

  37. Ferdinand Engelbeen:

    I your post at February 5, 2014 at 6:05 am you reply to johnmarshall:

    There is no guarantee that CO2 levels were 260ppmv back then. This figure is a guess from some climate model, ie. it was cold therefore CO2 levels had to be low. This does not follow ice core research which shows that the present increase of CO2 is likely due to the MWP not the paltry mass of CO2 we inject.

    Nothing to do with climate models, but that is what is found in ice cores:
    http://www.ferdinand-engelbeen.be/klimaat/klim_img/antarctic_cores_010kyr.jpg

    What you say is true but – as you know – the stomata data show much higher values.

    There are good reasons to dispute both the ice core data and the stomata data. They each provide useful information, but neither of these proxies provides an indication of true atmospheric CO2 concentration long ago. Sadly, some people champion one or the other depending on prejudice.

    Richard

  38. ROM says: @ February 3, 2014 at 6:56 pm

    …spare a thought for the plant breeders….
    >>>>>>>>>>>>>>>>>>>>>>
    Many of the plant breeders and those dedicated to preserving heritage breeds are amateurs doing it for nothing and thank goodness for those people who preserve the genetics not commercially economic. Purdue University found commercial poultry is at risk because of the reduced genetic diversity.

    This is why the UK/EU/OIE foot and Mouth fiasco that destroyed these UK herds of heritage breeds made so many people go ballistic. Because of the UN OIE and harmonization of laws similar problems are just waiting to happen in other countries. UK Report

    Vaccination could have been used but the EU/UK government rejected the use of vaccination.

    This is the reason depopulation and not vaccination was used:

    … Under the worldwide rules set by the OIE, a country can recover its disease-free status either three months after the end of the very last recorded outbreak, or 12 months after it has completed a vaccination programme. In this instance, if Britain had completed a vaccination programme in April 2001, and there had been no further recorded outbreaks, she could have recovered full trading status in April 2002. By rejecting vaccination, that status could only now be recovered three months after the last outbreak…

    So they had to keep killing animals as the disease spread. FMDV is VERY contagious. It can be found in all secretions and excretions from acutely infected animals, including expired air, saliva, milk, urine, feces and semen.

    Depopulation consists of: “… the affected herd and all cattle, sheep, goats, swine, and susceptible wildlife—infected or not— within a minimum 10-kilometer zone around the infected farm would be killed….” (USDA) and all structures not made of “…sound impervious surfaces which can be effectively decontaminated…should be removed for burning or burial…” (OIE) That means the farm dogs, cats and even the entire farm was destroyed in some cases and scores of farmers committed suicide.

    I do not know if any of the rare breeds were completely lost but the best bloodlines of the Herdwick sheep breed were saved through Heroic Intervention

    The Sheep Trust was founded from Heritage GeneBank – the organisation that helped to conserve sheep breeds at threat from extinction during the UK Foot and Mouth Disease epidemic of 2001.

    From the May 2001 telegraph:

    The importance of rare breeds of farm animals has been recognised by the Rare Breeds Survival Trust (RBST) for 28 years, and I have been involved in the conservation of such animals for much of that time…..

    But now large numbers have been caught up in the killing areas next to farms where foot and mouth is present, and those improvements have been knocked back 10 or 20 years. Astonishingly, we do not know the numbers of rare breeds lost in the contiguous cull, as there are no such statistics available. Maff publishes only details of those holdings confirmed as infected, and not the many more healthy animals on neighbouring land.

    The lesson that everyone has learnt over the past weeks is just how ill-prepared we are for such an epidemic as this. The RBST, on its own, has already put in place a gene bank of cattle and pig semen for just such an emergency. But lack of money has precluded any provision for sheep, goats, poultry or horse breeds, or for any embryos.

    http://www.telegraph.co.uk/comment/4261749/Rare-breeds-are-the-green-future-of-British-farming.html

    Unfortunately with the move of the Foot and Mouth lab (biological research facility) in the USA from Plum Island to the Manhattan Kansas, the middle of cow country. The UK fiasco was caused by a due to a biosecurity leak at Pirbright Labs. OH, and Foot and Mouth disease virus can remain alive in human. In humans FMDV may be carried in the nasal passages for up to 28 hours after exposure.

    Really makes you wonder about the idiocy of Governments. For me this incidence was the straw that broke the camel’s back even though I am in the USA and not the UK.

  39. SLCO2 @ Utah says: @ February 4, 2014 at 11:06 am

    …..The reality is that CO2 does NOT stay in the atmosphere for thousands of years and varies a lot from place to place, from year to year, from season to season, from day to day, and from night to day. In fact CO2 concentrations change all the time and there is NO SUCH THING as “Average World CO2″….
    >>>>>>>>>>>>>>>>>
    Completely agree.

    The other hilarious part of this study is corn and grasses are C4 plants and are not particularly responsive to CO2 increases to begin with!
    seedling growth C3 vs C4 at different CO2 concentrations once you hit about 200 ppm CO2 the C4 plants could care less.

  40. Samuel C Cogar said @ February 5, 2014 at 4:58 am

    Ah so, …. and me thinks the Cambrian Explosion is testimony to the fact that HGT occurs.
    Especially when one considers the potential fact that all DNA had to have been a much simpler form in that day and time.

    Oddly, the cnidarians genome contains a genetic toolkit for “higher” animals. The origin of the cnidarians is in the pre-Cambrian. You might find this interesting:

    http://onlinelibrary.wiley.com/doi/10.1002/bies.200900033/pdf

  41. richardscourtney says:
    February 5, 2014 at 6:29 am

    There are good reasons to dispute both the ice core data and the stomata data. They each provide useful information, but neither of these proxies provides an indication of true atmospheric CO2 concentration long ago.
    —————-

    First of all, I do not believe there is such a thing as a “true atmospheric CO2 concentration” …… but “true CO2 concentrations” do exist in “closed systems”, …. tanks, cylinders, etc.

    I can agree that ice core proxies do not provide a reliable indication of “average” atmospheric CO2 concentration simply because of the high variability of near-surface CO2 ppm and the fact that there is no correlation or association whatsoever between the highly variable CO2 ppm in the near-surface air ….. and the instant (time) the “snapshot” picture of said CO2 was recorded by its entrapment in the snowfall or wind blown snow.

    I am curious as to your reason for disclaiming fossilized plant stomata proxies of being reliable indicators of “average” atmospheric CO2 concentration.

    Now I agree that plants are subjected to the highly variable CO2 ppm in the near-surface air …. but the size and number of their stomata is not, …. was not, ….. an instant (time) “snapshot” picture of the CO2 in the near surface air.

    Thus, it is my learned opinion that the “average” near surface atmospheric CO2 ppm has to remain above a certain threshold for a considerable length of time (as compared to instant) before the plant will react to it by producing greater or lesser numbers of stomata in it’s new leaf growth.

    As far as I know, plants do not modify or change the number, size or location of the stomata in their leaves ….. after said leaves reach full maturity. But then I don’t know everything but am always willing to learn something new.

    Cheers

  42. The Pompous Git says:
    February 5, 2014 at 3:25 pm

    Oddly, the cnidarians genome contains a genetic toolkit for “higher” animals. The origin of the cnidarians is in the pre-Cambrian. You might find this interesting:
    ——————-

    Thanks Pompous Git, I did find that interesting, …. when they referred to it as “The Cambrian Conundrum” ….. and the parts I understood, that is. A lot of the vocabulary I am not fluent with but I did manage to get the gist of what it was saying.

    The part that intrigued the most was the text at the bottom right portion of page 740 where the author talks about ….. “different biota acquiring different numbers of novel miRNA families during the same time period”.

    Like vertebrates acquiring 40 novel families in the same time period that another group only acquired 5 – 8 novel families. ….. That “smells” to me like HGT in action. ha ha

  43. Samuel C Cogar said @ February 6, 2014 at 9:18 am

    The part that intrigued the most was the text at the bottom right portion of page 740 where the author talks about ….. “different biota acquiring different numbers of novel miRNA families during the same time period”.

    Like vertebrates acquiring 40 novel families in the same time period that another group only acquired 5 – 8 novel families. ….. That “smells” to me like HGT in action. ha ha

    Yes, smells like that to me, too. Glad you enjoyed it :-)

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