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Pollination - History Of Pollination Studies, Evolution Of Pollination, Wind Pollination, Pollination By Animals

pollen plants male female

Pollination is the transfer of pollen from the male reproductive organs to the female reproductive organs of A honeybee becomes coated in pollen while gathering nectar and transports the pollen as it goes from flower to flower. Photograph by M. Ruckszis. Stock Market/Zefa Germany. Reproduced by permission. a plant, and it precedes fertilization, the fusion of the male and the female sex cells. Pollination occurs in seed-producing plants, but not in the more primitive spore-producing plants, such as ferns and mosses. In plants such as pines, firs, and spruces (the gymnosperms), pollen is transferred from the male cone to the female cone. In flowering plants (the angiosperms), pollen is transferred from the flower's stamen (male organ) to the pistil (female organ). Many species of angiosperms have evolved elaborate structures or mechanisms to facilitate pollination of their flowers.


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almost 3 years ago

Dear Dr. ;
I suspect that you will find interesting a proposal that angiosperm plants evolved on the Ontong-Java Plateau before the Cretaceous in http://charles_w.tripod.com/ontong.html and below; You may see its publication in http://gsjournal.net/Science-Journals/Research%20Papers-Paleontology/Download/4719 . Also you may see an explanation for the boundaries of the temperate deciduous forest as a function of glaze ice storms in http://charles_w.tripod.com/glaze.html .
Sincerely, Charles Weber

PERMIAN MONSOON EVOLUTION OF ANGIOSPERMS to FURNISH DECIDUOUS GLAZE ICE TREES
by Charles Weber
Angiosperms had to have existed before the early Cretaceous when they appeared fully formed. I suspect they evolved since the Carboniferous on an island mini continent Angiosperm (also called magnoliophyta) deciduous dicotyledon trees have had much more success in surviving in glaze ice areas than other types of trees because of less branch breakage in winter time. They started to become established in North American subarctic regions in the Paleocene and were fully established before the Eocene closed. They probably descended largely from subtropical trees. I suspect that they may have evolved the precursor genes on a now submerged South Western Pacific mini continent, the Ontong Java Plateau, probably as early as the Permian, as a monsoon area adaptation. Their seeds were probably carried to the mainland on the feet of water birds and in the crops of seed eating birds.
For definitions of botanical terms see this site, along with a discussion of angiosperm evolution.
DISCUSSION
Angiosperms are unique in having aromatic amino acids and hydrolyzable tannins [Friis,p3]. Their carpels enclose their ovules and pollen tube growth goes through sporophytic carpel tissue [Friis, p2]. Their double fertilization of the egg cell and the endostem support tissue cell is also unique [Friedman]. All the continents have been thoroughly explored and no large angiosperm assemblage has been found anywhere before the Cretaceous. Evolution in tropical mountains [Axelrod (1952), p34] is impossible. Such an enormous assemblage of monocotyledons and dicotyledons would have been absolutely certain to have left many obvious lowland fossils in view of their considerable success not much later. Every other plant group can be traced back at least to the Permian and most go back to the Devonian. Angiosperms must go back to the Devonian [Stewart pp 128,169,212,313,348]. ]. Molecular evidence shows the monocotyledons separating from the dicotyledons 320 million years ago in lower Carboniferous [Martin et al, 1989]. Molecular analysis of other major divergences are 200 million years or more. There are leaves and flowers in Triassic Virginia [Cornet, 1993] and also pollen [Cornet, 1989] resembling angiosperms [Cornet, 1989] as well as aquatic fossils with fruit from late Jurassic in Central Asia [Sun, et al, 1998] [Sun, et al 2002], so it is plausible that angiosperm prototypes survived in small numbers as late as the Triassic or later on the continents. Isocarbinorinol, which only angiosperms have, has been found in the Permian [Haike, et al 1995] so this possibility is reinforced. There is even a report of pollen resembling angiosperm pollen from the Jurassic North Sea. [Abbink]. This pollen of a water plant could conceivably be an early migrant. A tropical island that could field so many tropical families would have to be large. A string of offshore volcanic islands or even peaks of a mountain range would be off by at least two orders of magnitude.
The only unexplored areas that I know of is in the western Pacific. Elevation of the Ontong Java Plateau, which is the largest oceanic plateau, would create a fair amount of tropical land, the size of Alaska or a major part of Australia, the largest oceanic plateau. Some of that area could have been monsoon climate that also can favor a deciduous habit. Seismic evidence indicates that this rise has continental characteristics with a crust over 35 km thick [Furomoto]. There is no evidence of flexure under the rise [Hussong] so the rise must go back to the very beginnings of earth history. If we drill through the basalt someday (not done to date [Kroenke] ) we may find coal or pollen underneath the basalt and thus possibly throw light on this. There has been fossil wood found in the basalt [Mahoney 2001] (the article containing this link is here, in which is also an extensive geological discussion). There also should be angiosperm pollen in mid Cretaceous sediments near the seamounts between the Ontong Java Plateau and Korea if this proposal is correct.. New Caledonia has many very primitive angiosperms [Carlquist p74]. Amborella tricopoda pollen from New Caledonia does not resemble angiosperm pollen. It is a pre-columellate type that precedes the Late Triassic Crinopolles angiosperm-like pollen in morphology. However, no angiosperm-like pollen has been reported from Gondwana during the Jurassic. The most primitive living angiosperm, Amborella, from New Caledonia does not produce pollen that can be called angiosperm-like (Sampson, 1993), meaning that its ancestors and close relatives could go unrecognized in the fossil palynological record. The restriction of most Triassic angiosperm-like fossils to North America, the presence of angiosperm-like pollen in the Early and Middle Jurassic of western Europe, and the presence of distinctive (i.e., diagnostic) angiosperm pollen in western Europe during the early Late Jurassic (Cornet and Habib, 1992), imply that angiosperms first evolved in Laurasia, or near there. See figures of Amborella tricopoda pollen in this site. [Sampson].
The absence of mammals on all the islands just mentioned imply a separation from the mainland going back possibly to the Triassic or further. The fact that angiosperms lacked an efficient means of dispersal by mammals in the first half of the Cretaceous [Schuster, p52,64] is circumstantial evidence that they came from an island continent. Fruits and barbs are late in angiosperms. Of course it is possible that mammals were confined to cold regions, so this could be weak circumstantial evidence, for angiosperm plants were almost certainly tropical then.
Boughey believes that most primitive angiosperms must have been beetle pollinated, probably from Permian [Boughey]. If so, this is further evidence for evolution going back to the Permian at least. Insect pollination is a major advantage for plants because pollen is rich in nitrogen and, more importantly, because insect pollination permits very small populations of any species in any particular area. Thus even plants with low incidence can survive, evolve, and manage to make it to numerous cul de sacs. Thus the already fairly large area of the Ontong Java Plateau for evolution would be greatly augmented.
It must seem obvious that the above discussion is at odds with some of current plate tectonic theory. However, shallow earthquakes under even the longest ridge-ridge transform faults and numerous other anomalies [Weber 1981] make it seem to me that these islands were always where they are now, for continents and plateaus with deep roots pushed along by thinner oceanic plates, all of the plates going in different random directions, is impossible. That deciduous evolution was at least partly subtropical in the Cretaceous, however, is almost certain. The first plants were herbaceous, insect pollinated, [Stewart p. 370], small, streamside, arid habitat, shrubs, [Hickey and Doyle] Seeds were possibly carried in the crops and on the feet of waterfowl. Conifers dominated the well drained uplands in early Cretaceous [Retallack]. Monocotyledons came much later to the continents followed by wind pollination [Stewart p. 373]. Further migrations had all the earmarks of intermittent arrivals. It was not until late in the Cretaceous that angiosperms moved toward the poles [Crane and Lidgard, 1989]; [Parish and Spicer, 1988] aided by a warming trend, probably by evolution in subtropical genera on the fringes. The Cretaceous was a rather warm time [Jenkyns, et al, 2004].
The colonization of the Northern Hemisphere by the hardwoods may have been considerably aided by the presence of Neotermes. This is a termite genus which was likely to have been able to eat live wood as early as the lower Cretaceous [Weber]. An ability to girdle taproots may have assisted it then and does today. There were no woodpeckers or Ponerine ants in monsoon areas, or other effective predators. Even if there had been woodpeckers, they would not have touched Neotermes if they had been like modern woodpeckers that do not [Kalshoven]. Strong wood with living tissue on the perimeter would have preadapted the above trees to a trend that was already visible in other early Cretaceous trees. Neotermes can not kill a hardwood unless the hardwood is also hard hit by drought or disease [Hill]. The ability of Neotermes to migrate on floating logs makes its early genesis less than certain, but its primitiveness [Snyder] makes it plausible. The later rise of the angiosperms to 85% of the fossil species [Axelrod (1966)] {but not necessarily 85% of the area covered} may have been assisted by the appearance of Coptotermes in the rain forest, which insect also uses live wood, toward the end of the Cretaceous in the Northern Hemisphere tropics. Most termite species can utilize susceptible live wood, but the appearance of angiosperms came almost certainly at least 50 million years after termites appeared as fossils so the vegetation must surely have evolved some chemical defenses against termites or their protozoa by the time angiosperms appeared as fossils. It is possible that Coptotermes ability to secrete its own cellulase [Hogan] may make Coptotermes able to utilize trees protected only by poisons against microorganisms. Its ability to ignore the Nasutitermes alarm pheromone secreted by pine trees (alpha & Beta pinenes) which prevent Nasutitermes from living under pine trees [Lee p7] must have assisted Neotermes in clearing away pine trees at least when Nasutitermes reached North America, since Nasutitermes probably evolved during the Cretaceous in South America and presumably Nasutitermes would have competed indirectly somewhat otherwise. Coptotermes presence by late Cretaceous is backed by present continental distribution but not by fossils yet. Its superior defense, utilizing a poisonous sticky secretion, must surely have made it successful even in rain forests, since there were probably no Dorylene ants in mid Cretaceous in the Northern Hemisphere (there is a good chance they were already in South America), and Ponerine ants probably did not then hunt in packs based on present day distribution.
Glaze ice must have existed in the late Cretaceous because there was deciduous vegetation in northwestern North America [Wolfe and Upchurch 1986]. Also rapid changes in sea level even before that time imply the presence of glaciers somewhere [Stoll].
Apparently the Carboniferous or Permian monsoon genes which preadapted angiosperms to glaze ice forests were already in place. Numerous tropical and subtropical genera moved into a climate zone, which today is centered in Northern Illinois during the Tertiary starting in late Cretaceous [Spicer] by displacing deciduous Metasequoia [Wolfe 1987 p219] and other deciduous conifers [Wolfe 1986]. The subtropical hardwood genera predominated, so that evergreen maples {Acer}, subtropical deciduous oaks {Quercus}, beeches {Fagus}, Sycamores {Platanus}, and subtropical maples {Acer}, as well as trees whose climate forebears were not specified by Axelrod such as hickories {Carya}, chestnuts {Castanea}, and elms {Ulmus} took over the canopy in the fertile heart of the glaze ice zone [Axelrod, 1966], leaving tropical and other subtropical genera to fill in the chinks, the understory, sandy or acid soils, the periphery, the disturbed areas, and the swamps. Almost all of the above hardwoods were or became deciduous.
There must have been a zone of glaze ice in Alaska if this hypothesis is valid because several species of southern Appalachian plants are also known in Asia [Braun pp515-517, 460]. Therefore it is conceivable that at least a narrow band of glaze ice existed across the Bering Straits bridge Pliocene or earlier. Deciduous trees in high latitudes is plausible because deciduous trees were not displaced far south by the glaciers except for a narrow band in front [Braun p517]. The Paleocene vegetation at 66 degrees north was largely deciduous [Wolfe 1987] [Also see a pollen analysis for the last 28,000 years. Scroll down to a link to maps at the bottom.], which lends plausibility to the above statement. If this hypothesis is valid, it explains why the extravagant deciduous trees which lose all their leaves annually, hang their soft edible leaves out within easy reach of sucking and other insects and vertebrates, and show extreme difficulty when competing with pines and sequoias over vast cool areas, nevertheless make almost monolithic stands in a gerrymandered area which cuts across isopleths of humidity, temperature, rainfall, light duration, light angular incidence, soil, fire, and nutrient status in temperate regions.
REFERENCES are below
SOME LINKS to SIMILAR ARTICLES
Effects of insects on ancient soils
Permian marine phosphorus as caused by amphibians, especially dragonflies
Cretaceous marine phosphorus as caused by runway building termites, or to the effect of runway builders and incompetent ants on the phosphorus of Cretaceous soils and vertebrate bones and teeth especially dinosaurs.
For more details of the termite effect see the termites' affect on soil around the Paleocene and a discussion of modern termites’ affects on soils.
For a hypothesis which explains loss of silica from tropical soils by the alkaline gut of termites see Did the alkaline gut of termites cause laterization of soils?
For those interested in dragonflies try IORI
For those interested in modern termites try this extensive worldwide discussion
For an electronic journal on paleontology see Palaeontologia Electronica at Paleonet
and See this site about insects
For a hypothesis about human female evolution see this URL..
LINKS TO SOME HEALTH ARTICLES
Arthritis treated by potassium in food.
The effect of copper nutrition on slipped discs, aneurysms, emphysema, gray hair, anemia, and hemorrhoids
Some suggestions for ameliorating chronic fatigue syndrome and fibromyalgia.
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There is an an article discussing cashew nuts to cure a tooth abscess Which might prove useful.
There is also an article which proposes some speculation about diabetes.
There is a site that contains reviews of natural remedies for many diseases .
For a procedure that discusses tetrathiomolybdate for removing copper and thus preventing further solid cancer growth and Hodgkin’s, see this site. This might buy some time for this and possibly other cancers until you can persuade a doctor to try tumor necrosis factor or interferon or an opioid antagonist drug called Naltrexone (Naltrexone in the large 50mg size, originally manufactured by DuPont under the brand name ReVia, is now sold by Mallinckrodt as Depade and by Barr Laboratories under the generic name naltrexone) that blocks some endorphin receptors. Said blockage is thought to cause the body to temporarily secrete more endorphins, especially after midnight at night. These endorphins are thought to stimulate the immune system, and in particular to stimulate the TH-1 or type 1 antiviral response by decreased interleukin-4 and with increased gamma interferon and interleukin-2 and a simultaneous decrease of type 2 anti bacterial response [Sacerdote]. It appears to be especially effective for minimizing symptoms and retarding progression of multiple sclerosis (MS) (also see these sites hereand here and this site) and. A few doctors have had encouraging results in Crohn's Disease (prompting Penn State College of Medicine to plan 4mth Study of Crohn's Disease & LDN and) CFIDS, and even to some extent in cancer. Low doses of Naltrexone (LDN), 1.5 to 4.5 milligrams, at bedtime is used (timing is important, and it is important not to buy slow release forms). It is said to have no known bad side effects at those doses other than stimulate the TH-1 or type 1 antiviral response by decreased interleukin-4 and with increased gamma interferon and interleukin-2 and a simultaneous decrease of type 2 anti bacterial response [Sacerdote]. 'Case Health - Health Success Stories' website collects and shares patient testimony of success. On 'Case Health' you'll find rave reports from quite a few patients who have submitted stories to this searchable database. The present MS Access database is cumbersome and slow - you'll need to be patient. The button for the engine is on the left side and the key word "LDN" will access multiple LDN related stories. There is also reports from an extensive survey in this site. I think some clinical studies on Naltrexone are in order, and it should not be a prescription drug. Though side effects appear unlikely, it is not proven over longer periods. If you try it (it is a prescription medicine in the USA), it seems likely that you should discontinue if you get a bacterial infection in view of its inhibition of antibacterial response. Naltrexone is currently being used by Dr. Enlander, a New York City doctor, but with limited success for chronic fatigue syndrome using 3 to 4.5 milligram doses for CFIDS.
Olive leaf extract has shown clinical evidence of effectiveness against a wide range of viruses, including AIDS [Bihari], herpes, and cold viruses. It sometimes produces a Herxheimer or pathogen die off symptoms (from effectiveness against bacteria?). There is evidence that it is synergistic (reinforce each other) with Naltrexone. There have been a few case histories of improvement in what were probably arthritis patients and CFIDS patients. The active ingredient is said to be oleuropein or enolate. There has been very little follow up research done on it.
. Also it has been found that curcumin in turmeric or curry powder will inhibit several forms of cancer, including melanoma. People who live in India where these spices are eaten, have one tenth the cancer elsewhere. Here is an article with anecdotal evidence for pressurized oxygen, zinc, vitamin B6, and vitamin C after head injuries. They also claim a fair percentage of prison inmates from psychiatric disorders after head injuries.
See this site for evidence of a correlation between magnesium deficiency and cancer. It has been found that supplements of the amino acid, taurine, will restore the abnormal electrocardiogram present during a potassium deficiency by an unknown mechanism. This information has been used in a single case history by George Eby [private communication] to control a long standing type of cardiac arrhythmia called pre atrial contractions (PACs), a benign but irritating and nerve racking heart problem, with 2.5 grams of taurine with each meal. You may see a discussion of the practical aspects of supplementation with taurine and food sources, including possible use for high blood pressure, migraine headache, and depression here.
A site is available which shows. foods which are high in one nutrient and low in another (including calories). This last site should be especially useful for a quick list of foods to consider first, or for those who must restrict another nutrient because of a genetic difficulty with absorption or utilization
There is a site with several links to potassium nutrition articles and another site that has many links to nutrition sites around the world.
There is a site with numerous links to arthritis amelioration, which stress a healthy life style.
If you use medication, you may see technical evaluations and cautions of drugs at the bottom of this site.
The very extensive USDA Handbook #8 may be seen here. To access the information you must press "enter" to search, and then divide Kcal into milligrams of potassium. This last table is very comprehensive, is used in search mode, and even lists the amino acids. There are also links in it to PDF types of printouts from the table for individual nutrients available here Just click on the “A” or “W” button for the nutrient you desire. A table that has already done the potassium calculation is here in descending concentration or in alphabetical order.
The health of people in the USA is abysmal (numerous statistics), and a major part of it is poor nutrition. As the 12th century physician, trying to cure by diet before he administers drugs, said; “No illness that can be treated by diet should be treated by any other means" or as Hippocrates expressed it in 460 - 377BC; "If we could give every individual the right amount of nourishment and exercise, not too little and not too much, we would have found the safest way to health." It would seem that a healthy life style has been known for a long time. It is my belief that an unprocessed, unfrozen, not canned, high in vegetables diet would keep a large majority of people reasonably healthy and without the need for fad diets. 80% of Americans do not eat adequate vegetables, but even though 72% of Americans take vitamin or mineral supplements daily or sometimes [Sardi p148], their health is atrocious, especially old people..
I would suggest that a partial solution to the problem of poor potassium nutrition would be to place a tax on all food that has had potassium removed by food processors and completely fund all Medicare and workman’s compensation for injuries and disease that relate to rheumatoid arthritis, heart disease, and high blood pressure. This would also take the onerous tax burden now incurred for them and place it on the shoulders of those who cause the problem
There is a free browser called Firefox, which is said to be less susceptible to viruses or crashes, has many interesting features, imports information from Iexplore while leaving Iexplore intact. You can also install their emailer. A feature that lists all the URLs on a viewed site can be useful when working on your own site.
If you have Iexplore, there is a tool bar by Google that enables you to search the internet from the page viewed, mark desired words, search the site, give page rank, etc.
There is a free program available which tells on your site what web site accessed you, which search engine, statistics about which country, statistics of search engine access, keywords used and their frequency. It can be very useful.
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Axelrod, D,I, 1952, A theory of angiosperm evolution. Evolution 6: 29.
Axelrod, D.I. 1966. Origin of deciduous and evergreen habits in temperate forests. Evolution 20, 1.
Boughey AS 1959 Origin and dispersal of flowering plants. Nature 184; 1200-1201.
Braun, E.L. 1972. Deciduous forests of eastern North America. Hafner Pub., NY.
Carlquist, S., 1965. Island Life Natural History Press, Garden City Press.
Cornet, B. 1989. Late Triassic angiosperm-like pollen from the Richmond Rift Basin of Virginia, USA. Palaeontographica Beitrage zur Naturgeschichte der Vorzeit 213 B, 37-87.
Cornet B Habib D 1992 Angiosperm-like pollen from the ammonite-dated Oxfordian (Upper Jurassic) of France. Review of Palaeobotany and Palynology, 7l : 269-294.
Cornet, B. 1993. Dicot-like leaf and flowers from he late Triassic tropical Newark supergroup riftzone, USA. Modern Geology 19, 81-99.
Crane, P.R., Lidgard, S. 1989. Angiosperm diversification and paleolatitudinal gradients in Cretaceous. Science 246, 675-8.
Dejersey, N.J., Grantmackie, J.A. 1989. Palynofloras from the Permian, Triassic, and Jurassic of New Caledonia. New Zealand J Geology & Geophysics 32, 463-476.
Field TS Arens NC Dawson TE 2003 The Ancestral Ecology of Angiosperms: Emerging Perspectives from Extant Basal Lineages. International Journal of Plant Sciences 164; S129-S143.
Friedman WE 2006 Embryological evidence for developemental lability during early angiosperm evolution. Nature 441; 337-340.
Furomoto, A.S., Webb, J.P., Odegard, M.E., Hussong, D.M. 1976. Seismic studies on the Ontong-Java Plateau. Tectonophysics. 34, 71-90.
Haike, V., Adam, P., Trendel, J.M., Albrecht, P., Schwark, L., Vliex, M., Hagemann, H., Puttmann, W. 1995. Isocarbanol through geological times: evidence for its presence in the Permian and Triassic. Organic Geochemistry 23, 91-93.
Hickey, L.J., Doyle, J.A. 1977 Early Cretaceous fossil evidence for angiosperm evolution. Botanical Review 43, 3-104.
Hill, G.F. 1921. The white ant pest in northern Australia. Bull. No. 21 Commonwealth of Australia; Melbourne, Australia. Hogan, M.E. Shulz, M.W., Slaytor, M. Cozolii, R.T. Obrien, R.W. 1988. Components of termite and protozoal cellulases from the lower termite, Coptotermes lacteus Froggatt. Insect Biochem 18, 45- 51.
Hussong, D.M., Wippeman, L.K., Kroenke, L.W. 1979. The crustal structure of the Ontong Java and Manihiki Oceanic Plateaus. J. Geophys. Res. 84, 6003-6010.
Jenkyns, H.C., Forster, A., Schouten, S., Damste, J.S.S. 2004 High temperatures in the late Cretaceous ocean. Nature 432, 888-892.
Kalshoven, L.G.E. 1959 Observations on the nests of initial colonies of Neotermes tectonae Damm in teak trees. Insects Sociaux 6, 231- 242.
Kolukisaoghi, H.V., Marx, S., Wiegman, C., Hanelt, S, Schneider-Poetsch, H.A.W. Divergence of the phytochrome gene family predates angiosperm evolution and suggests that Selaginella and Equisetum arose prior to Psilotium. Journal of Molecular Evolu tion 41, 329-337.
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