veracity of evolution

ok none of these guys are BIOLOGISTS and none of them are arguing against the theory of evolution either

btw Hawkings is agnostic



none of these guys are leading figures in biology

in fact

A Scientific Dissent From Darwinism - Wikipedia, the free encyclopedia
[INDENT]The Scientific Dissent From Darwinism document has been widely criticized on several different grounds. First, similar to previous lists produced by other creationists, the professional expertise of those listed is not always apparent and is alleged to be deficient.[38] Also, the professional affiliations and credentials that are claimed for some of the signatories has been questioned. Finally, there appear to be a few who appear on the list who are not firmly committed to the agenda advanced by the Discovery Institute, and who have been misled into signing or who have changed their minds. Russell D. Renka, a political scientist, said that the Discovery Institute presented the list in an appeal to authority to support its anti-evolution viewpoint.[39]
A paper from a think tank, the Center for Inquiry said that Dissent From Darwinism is one of the Discovery Institute intelligent design campaigns to discredit evolution and bolster claims that intelligent design is scientifically valid by creating the impression that evolution lacks broad scientific support.[40]
In November 2001, the National Center for Science Education stated that the then current version of the document appeared "to be very artfully phrased" to represent a diverse range of opinions, set in a context which gives it a misleading spin to confuse the public.[12]

[edit] Expertise relevance

The listed affiliations and areas of expertise of the signatories have also been criticized.[13][5][1]
In addition, the list was signed by only about 0.01% of scientists in the relevant fields. According to the National Science Foundation, there were approximately 955,300 biological scientists in the United States in 1999.[41] The theory of evolution is overwhelmingly accepted throughout the scientific community.[21] Professor Brian Alters of McGill University, an expert in the creation-evolution controversy, is quoted in an article published by the NIH as stating that "99.9 percent of scientists accept evolution".[22]
The list has been criticized by many organizations and publications for lacking any true experts in the relevant fields of research, primarily biology. Critics have noted that of the 105 "scientists" listed on the original 2001 petition, fewer than 20% were biologists, with few of the remainder having the necessary expertise to contribute meaningfully to a discussion of the role of natural selection in evolution.[13][12]

[edit] Other criticisms

Critics have also noted that the wording and advertising of the original statement was, and remains, misleading,[12] and that a review of the signatories suggested many doubt evolution due to religious, rather than scientific beliefs.[13] The claims made for the importance of the list have also been called intellectually dishonest because it represents only a small fraction of the scientific community,[5] and includes an even smaller number of relevant experts.[42] The Discovery Institute has responded to some of these criticisms.[43][44]

[edit] Affiliations and credentials

Barbara Forrest and Glenn Branch say the Discovery Institute deliberately misrepresents the institutional affiliations of signatories of the statement "A Scientific Dissent from Darwinism". The institutions appearing in the list are the result of a conscious choice by the Discovery Institute to only present the most prestigious affiliations available for an individual. For example, if someone was trained at a more prestigious institution than the one they are presently affiliated with, the school they graduated from will more often be listed, without the distinction being made clear in the list. This is contrary to standard academic and professional practice and, according to Forrest and Branch, is deliberately misleading.[1]
For example, the institutions listed for Raymond G. Bohlin, Fazale Rana, and Jonathan Wells, were the University of Texas, Ohio University, and the University of California, Berkeley respectively, the schools from which they obtained their Ph.D. degrees. However, their present affiliations are quite different: Probe Ministries for Bohlin, the Reasons to Believe Ministry for Rana, and the Discovery Institute's Center for Science and Culture for Wells.[1]
Many of those who have signed the list are not currently active scientists, and some have never worked as scientists.
Also, if a signatory was previously the head of a department or the president of an institute, their past and most prestigious position will be listed, not their current position. For example, Ferenc Jeszenszky is a physicist in Budapest who handles the "Hungarian Creation Research" videos, but appears instead on the list as "Former Head of the Center of Research Groups, Hungarian Academy of Sciences".[citation needed]
Visitors at prestigious institutions will have that affiliation listed, not their more humble home institutions. For example, Bernard d'Abrera, a writer and publisher of books on butterflies, appears on the list as "Visiting Scholar, Department of Entomology British Museum (Natural History)", in spite of the fact that this museum had become independent of the British Museum three decades previously and had formally changed its name to the Natural History Museum almost a decade before the petition. d'Abrera's primary affiliation is with his publishing company, Hill House Publishers. d'Abrera does not have a PhD either, nor any formal scientific qualification (his undergraduate degree was a double major in History & Philosophy of Science, and History), although creationists often call him "Dr. d'Abrera".[45][46] The Discovery Institute currently recruits people with PhDs to sign the Dissent petition.[47]
At least one other signatory, Forrest Mims, has neither a PhD nor any formal academic training in science. Additionally, at least seven signatories have their advanced degrees from outside the areas of "engineering, mathematics, computer science, biology, chemistry, or one of the other natural sciences" that are currently being recruited: Ronald R. Crawford has his Ed.D. in Science Education, David Berlinski has his PhD in Philosophy, Tom McMullen has his PhD in the History & Philosophy of Science, Angus Menuge has his PhD in the Philosophy of Psychology, Stephen Meyer has his PhD in the Philosophy of Science, Tony Prato has his PhD in Agricultural Economics,[48] and Tianyou Wang has his PhD in Education[49] and at least six, Jeffrey M. Schwartz[50] (incorrectly listed as "Ricardo Leon"), Gage Blackstone, Daniel Galassini, Mary A. Brown and Thomas C. Majerus, have professional doctorates (such as an MD, DVM or PharmD), rather than holding a research doctorate (such as a PhD).[improper synthesis?]
Also, in early editions of the list, Richard Sternberg was described as "Richard Sternberg, Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution" though Sternberg was never a Smithsonian staff member, but an unpaid research associate.[3] At the time of signing the list Sternberg was the outgoing editor of the Proceedings of the Biological Society of Washington, a minor biology journal, where he played a central role in the Sternberg peer review controversy. Later versions of the list dropped mention of Sternberg's affiliation with the Smithsonian[51] in favor of Sternberg's alma maters, Florida International University and Binghamton University. At present Sternberg is a Staff Scientist with GenBank, the genetic database at the National Institutes of Health.[52][improper synthesis?]
Critics also say the Discovery Institute inflates the academic credentials and affiliations of signatories such as Henry F. Schaefer. The institute prominently and frequently asserts that Schaefer has been nominated for the Nobel Prize in Chemistry.[3][53] Barbara Forrest and others allege that the Discovery Institute is inflating his reputation by constantly referring to him as a "five-time nominee for the Nobel Prize" despite that Nobel Prize nominations remain confidential for fifty years[1] and there being about 250-300 nominations per prize per year.[54]
By analysing the data for 34 British, or British-trained signatories of the Dissent list, the anti-creationist British Centre for Science Education raised doubts about the claimed affiliations and relevant expertise of those on the list.[55]

[edit] Defections and disagreements

The National Center for Science Education interviewed a sample of the signatories, and found that some were less critical of "Darwinism" than the advertisement claimed.[12][56] For example, Stanley N. Salthe, a visiting scientist at Binghamton University, State University of New York, who signed but describes himself as an atheist, said that when he endorsed a petition he had no idea what the Discovery Institute was. Salthe stated, "I signed it in irritation."[57] However, Salthe prominently appears on the list as "Emeritus Professor, Biological Sciences, Brooklyn College of the City University of New York."
At least one signatory of A Scientific Dissent From Darwinism has abandoned the list, saying he felt misled. Robert C. Davidson, a Christian, scientist, doctor, and retired nephrology professor at the University of Washington medical school said after having signed he was shocked when he discovered that the Discovery Institute was calling evolution a "theory in crisis." "It's laughable: There have been millions of experiments over more than a century that support evolution," said Davidson. "There's always questions being asked about parts of the theory, as there are with any theory, but there's no real scientific controversy about it." "When I joined I didn't think they were about bashing evolution. It's pseudo-science, at best ... What they're doing is instigating a conflict between science and religion."[58]
[/INDENT]

this bears repeating:

[indent]In addition, the list was signed by only about 0.01% of scientists in the relevant fields. According to the National Science Foundation, there were approximately 955,300 biological scientists in the United States in 1999.[41] The theory of evolution is overwhelmingly accepted throughout the scientific community.[21] Professor Brian Alters of McGill University, an expert in the creation-evolution controversy, is quoted in an article published by the NIH as stating that "99.9 percent of scientists accept evolution".[22] The list has been criticized by many organizations and publications for lacking any true experts in the relevant fields of research, primarily biology. Critics have noted that of the 105 "scientists" listed on the original 2001 petition, fewer than 20% were biologists, with few of the remainder having the necessary expertise to contribute meaningfully to a discussion of the role of natural selection in evolution.[13][12][/indent]


you are really grasping at straws now


the overwhelming majority of scientists both in and outside of the field of biology accept the theory of evolution and you blow an extremely dubious creationist propaganda website out of proportion as if it represents anything other than fringe lunacy and outright lying

oops double post damn connection

For those of us who treat HIV, we see it happening right in front of our eyes.

here's a breakdown of scientists' acceptance of the theory of evolution overall in case anyone is still confused

Can you define what they are accepting? I mean, the term evolution is so broad, that if one denies it one would have to deny day to day or even minute to minute changes in the individual human body. So what exactly are we talking about when we say the Theory of Evolution?

This is how Wikipedia defines it:

Evolution - Wikipedia, the free encyclopedia

I personally cannot discuss whether something is a fact or not until I know what we are talking about.

Rich

---------- Post added 08-25-2009 at 08:55 AM ----------



Yes, Paul, if indeed this is what we are talking about. Thousands of years ago, both Western and Eastern philosophers proclaimed all is in flux.

But are we talking about what is right in front of out eyes, or a process that may or may not have occurred millions of years ago?

Rich

Hmmmm that looks like the exact same graph as scientists who supported the fertility drug thalidomide.

You said there were no reputable scientists that disputed evolution. I just gave a large list. Mit scientists and physicists who disagree with you and challenge you on your declaration. You are a very arrogant young man arent you to spit in the faces of these extremely knowledgeable talents. I can gather many more from the internet I am sure but as far as I can see you will just simply dismiss them with some homemade graph with absoluteluy no factual structure whatsoever. After seeing that ridiculous graph you made your idea of fact and mine are extreme opposites and that is a fact.

I've made my point, and now that we have entered into the realm of ridiculous it is time for me to bow out.

the wikipedia definition is brilliant



right, Satan buried all those fossils. or maybe they were great dragons of yore

I likewise reserve judgment on the Holocaust

the Jewish version of events seems fishy

So you have seen a half man half monkey that is not either a monkey or a man?

How about a bird that is half bird or half reptile? Seen one of those lately flying through the air? Far as I am aware the closest thing to anything like that was a dinosaur. I am pretty sure we have nothing in the wilderness today that could be considered neither bird nor reptile but is somewhere between en evolved state of the two.

If you concur that evolutions has been occurring for billions of years than why is there not some creature present right now that is showing this obvious state of evolution? Maybe we are just living in a lull right now are we?

Thats it, this like the eye of a hurricane where evolution is taking a break.

Wait a minute, there is one creature right on this forum that is definitely not human and yet not quite animal either. hmmmmmmm

Well, the Wikipedia definition is pretty broad. So, rather than discuss whether or not things are constantly changing, I will just refer to this from the Wikipedia definition:

current research in evolutionary biology deals with several areas where the modern evolutionary synthesis may need modification or extension.

We'll see how many facts will change over time. Everything seems to evolve, including facts.

Rich

really? where is that graph?

doesn't your lower intestine get sore after you pull so many things out of it?



your list is extremely dubious, and puny. there are hundreds of thousands of biological scientists in America alone, and a few hundred signatories, 20% of whom are in a biological field, some of whom aren't actually even scientists, others of whom want their name removed from the list, and none of whom are world-ranking experts, don't mean ****

your list is worst than the Inhofe list of global warming skeptics



whoa whoa whoa hold the phone

what "MIT scientists and physicists" are arguing against Darwin's theory of evolution?

you haven't produced one



no it is you who are very arrogant to ignore the overwhelmingly vast majority of scientists, in particular biological scientists, who have no qualms about accepting the truth



my graph was drawn from NIH data

also when you use phrases like "absolutely no factual structure whatsoever" you are trying way too hard to sound erudite



don't let the door ...

---------- Post added 08-25-2009 at 10:20 AM ----------



Observed Instances of Speciation

[indent]5.0 Observed Instances of Speciation

The following are several examples of observations of speciation.
5.1 Speciations Involving Polyploidy, Hybridization or Hybridization Followed by Polyploidization.



5.1.1 Plants

(See also the discussion in de Wet 1971).
5.1.1.1 Evening Primrose (Oenothera gigas)

While studying the genetics of the evening primrose, Oenothera lamarckiana, de Vries (1905) found an unusual variant among his plants. O. lamarckiana has a chromosome number of 2N = 14. The variant had a chromosome number of 2N = 28. He found that he was unable to breed this variant with O. lamarckiana. He named this new species O. gigas.
5.1.1.2 Kew Primrose (Primula kewensis)

Digby (1912) crossed the primrose species Primula verticillata and P. floribunda to produce a sterile hybrid. Polyploidization occurred in a few of these plants to produce fertile offspring. The new species was named P. kewensis. Newton and Pellew (1929) note that spontaneous hybrids of P. verticillata and P. floribunda set tetraploid seed on at least three occasions. These happened in 1905, 1923 and 1926.
5.1.1.3 Tragopogon

Owenby (1950) demonstrated that two species in this genus were produced by polyploidization from hybrids. He showed that Tragopogon miscellus found in a colony in Moscow, Idaho was produced by hybridization of T. dubius and T. pratensis. He also showed that T. mirus found in a colony near Pullman, Washington was produced by hybridization of T. dubius and T. porrifolius. Evidence from chloroplast DNA suggests that T. mirus has originated independently by hybridization in eastern Washington and western Idaho at least three times (Soltis and Soltis 1989). The same study also shows multiple origins for T. micellus.
5.1.1.4 Raphanobrassica

The Russian cytologist Karpchenko (1927, 1928) crossed the radish, Raphanus sativus, with the cabbage, Brassica oleracea. Despite the fact that the plants were in different genera, he got a sterile hybrid. Some unreduced gametes were formed in the hybrids. This allowed for the production of seed. Plants grown from the seeds were interfertile with each other. They were not interfertile with either parental species. Unfortunately the new plant (genus Raphanobrassica) had the foliage of a radish and the root of a cabbage.
5.1.1.5 Hemp Nettle (Galeopsis tetrahit)

A species of hemp nettle, Galeopsis tetrahit, was hypothesized to be the result of a natural hybridization of two other species, G. pubescens and G. speciosa (Muntzing 1932). The two species were crossed. The hybrids matched G. tetrahit in both visible features and chromosome morphology.
5.1.1.6 Madia citrigracilis

Along similar lines, Clausen et al. (1945) hypothesized that Madia citrigracilis was a hexaploid hybrid of M. gracilis and M. citriodora As evidence they noted that the species have gametic chromosome numbers of n = 24, 16 and 8 respectively. Crossing M. gracilis and M. citriodora resulted in a highly sterile triploid with n = 24. The chromosomes formed almost no bivalents during meiosis. Artificially doubling the chromosome number using colchecine produced a hexaploid hybrid which closely resembled M. citrigracilis and was fertile.
5.1.1.7 Brassica

Frandsen (1943, 1947) was able to do this same sort of recreation of species in the genus Brassica (cabbage, etc.). His experiments showed that B. carinata (n = 17) may be recreated by hybridizing B. nigra (n = 8) and B. oleracea, B. juncea (n = 18) may be recreated by hybridizing B. nigra and B. campestris (n = 10), and B. napus (n = 19) may be recreated by hybridizing B. oleracea and B. campestris.
5.1.1.8 Maidenhair Fern (Adiantum pedatum)

Rabe and Haufler (1992) found a naturally occurring diploid sporophyte of maidenhair fern which produced unreduced (2N) spores. These spores resulted from a failure of the paired chromosomes to dissociate during the first division of meiosis. The spores germinated normally and grew into diploid gametophytes. These did not appear to produce antheridia. Nonetheless, a subsequent generation of tetraploid sporophytes was produced. When grown in the lab, the tetraploid sporophytes appear to be less vigorous than the normal diploid sporophytes. The 4N individuals were found near Baldwin City, Kansas.
5.1.1.9 Woodsia Fern (Woodsia abbeae)

Woodsia abbeae was described as a hybrid of W. cathcariana and W. ilvensis (Butters 1941). Plants of this hybrid normally produce abortive sporangia containing inviable spores. In 1944 Butters found a W. abbeae plant near Grand Portage, Minn. that had one fertile frond (Butters and Tryon 1948). The apical portion of this frond had fertile sporangia. Spores from this frond germinated and grew into prothallia. About six months after germination sporophytes were produced. They survived for about one year. Based on cytological evidence, Butters and Tryon concluded that the frond that produced the viable spores had gone tetraploid. They made no statement as to whether the sporophytes grown produced viable spores.
5.1.2 Animals

Speciation through hybridization and/or polyploidy has long been considered much less important in animals than in plants [[[refs.]]]. A number of reviews suggest that this view may be mistaken. (Lokki and Saura 1980; Bullini and Nascetti 1990; Vrijenhoek 1994). Bullini and Nasceti (1990) review chromosomal and genetic evidence that suggest that speciation through hybridization may occur in a number of insect species, including walking sticks, grasshoppers, blackflies and cucurlionid beetles. Lokki and Saura (1980) discuss the role of polyploidy in insect evolution. Vrijenhoek (1994) reviews the literature on parthenogenesis and hybridogenesis in fish. I will tackle this topic in greater depth in the next version of this document.
5.2 Speciations in Plant Species not Involving Hybridization or Polyploidy



5.2.1 Stephanomeira malheurensis

Gottlieb (1973) documented the speciation of Stephanomeira malheurensis. He found a single small population (< 250 plants) among a much larger population (> 25,000 plants) of S. exigua in Harney Co., Oregon. Both species are diploid and have the same number of chromosomes (N = 8). S. exigua is an obligate outcrosser exhibiting sporophytic self-incompatibility. S. malheurensis exhibits no self-incompatibility and self-pollinates. Though the two species look very similar, Gottlieb was able to document morphological differences in five characters plus chromosomal differences. F1 hybrids between the species produces only 50% of the seeds and 24% of the pollen that conspecific crosses produced. F2 hybrids showed various developmental abnormalities.
5.2.2 Maize (Zea mays)

Pasterniani (1969) produced almost complete reproductive isolation between two varieties of maize. The varieties were distinguishable by seed color, white versus yellow. Other genetic markers allowed him to identify hybrids. The two varieties were planted in a common field. Any plant's nearest neighbors were always plants of the other strain. Selection was applied against hybridization by using only those ears of corn that showed a low degree of hybridization as the source of the next years seed. Only parental type kernels from these ears were planted. The strength of selection was increased each year. In the first year, only ears with less than 30% intercrossed seed were used. In the fifth year, only ears with less than 1% intercrossed seed were used. After five years the average percentage of intercrossed matings dropped from 35.8% to 4.9% in the white strain and from 46.7% to 3.4% in the yellow strain.
5.2.3 Speciation as a Result of Selection for Tolerance to a Toxin: Yellow Monkey Flower (Mimulus guttatus)

At reasonably low concentrations, copper is toxic to many plant species. Several plants have been seen to develop a tolerance to this metal (Macnair 1981). Macnair and Christie (1983) used this to examine the genetic basis of a postmating isolating mechanism in yellow monkey flower. When they crossed plants from the copper tolerant "Copperopolis" population with plants from the nontolerant "Cerig" population, they found that many of the hybrids were inviable. During early growth, just after the four leaf stage, the leaves of many of the hybrids turned yellow and became necrotic. Death followed this. This was seen only in hybrids between the two populations. Through mapping studies, the authors were able to show that the copper tolerance gene and the gene responsible for hybrid inviability were either the same gene or were very tightly linked. These results suggest that reproductive isolation may require changes in only a small number of genes.
5.3 The Fruit Fly Literature



5.3.1 Drosophila paulistorum

Dobzhansky and Pavlovsky (1971) reported a speciation event that occurred in a laboratory culture of Drosophila paulistorum sometime between 1958 and 1963. The culture was descended from a single inseminated female that was captured in the Llanos of Colombia. In 1958 this strain produced fertile hybrids when crossed with conspecifics of different strains from Orinocan. From 1963 onward crosses with Orinocan strains produced only sterile males. Initially no assortative mating or behavioral isolation was seen between the Llanos strain and the Orinocan strains. Later on Dobzhansky produced assortative mating (Dobzhansky 1972).
5.3.2 Disruptive Selection on Drosophila melanogaster

Thoday and Gibson (1962) established a population of Drosophila melanogaster from four gravid females. They applied selection on this population for flies with the highest and lowest numbers of sternoplural chaetae (hairs). In each generation, eight flies with high numbers of chaetae were allowed to interbreed and eight flies with low numbers of chaetae were allowed to interbreed. Periodically they performed mate choice experiments on the two lines. They found that they had produced a high degree of positive assortative mating between the two groups. In the decade or so following this, eighteen labs attempted unsuccessfully to reproduce these results. References are given in Thoday and Gibson 1970.
5.3.3 Selection on Courtship Behavior in Drosophila melanogaster

Crossley (1974) was able to produce changes in mating behavior in two mutant strains of D. melanogaster. Four treatments were used. In each treatment, 55 virgin males and 55 virgin females of both ebony body mutant flies and vestigial wing mutant flies (220 flies total) were put into a jar and allowed to mate for 20 hours. The females were collected and each was put into a separate vial. The phenotypes of the offspring were recorded. Wild type offspring were hybrids between the mutants. In two of the four treatments, mating was carried out in the light. In one of these treatments all hybrid offspring were destroyed. This was repeated for 40 generations. Mating was carried out in the dark in the other two treatments. Again, in one of these all hybrids were destroyed. This was repeated for 49 generations. Crossley ran mate choice tests and observed mating behavior. Positive assortative mating was found in the treatment which had mated in the light and had been subject to strong selection against hybridization. The basis of this was changes in the courtship behaviors of both sexes. Similar experiments, without observation of mating behavior, were performed by Knight, et al. (1956).
5.3.4 Sexual Isolation as a Byproduct of Adaptation to Environmental Conditions in Drosophila melanogaster

Kilias, et al. (1980) exposed D. melanogaster populations to different temperature and humidity regimes for several years. They performed mating tests to check for reproductive isolation. They found some sterility in crosses among populations raised under different conditions. They also showed some positive assortative mating. These things were not observed in populations which were separated but raised under the same conditions. They concluded that sexual isolation was produced as a byproduct of selection.
5.3.5 Sympatric Speciation in Drosophila melanogaster

In a series of papers (Rice 1985, Rice and Salt 1988 and Rice and Salt 1990) Rice and Salt presented experimental evidence for the possibility of sympatric speciation. They started from the premise that whenever organisms sort themselves into the environment first and then mate locally, individuals with the same habitat preferences will necessarily mate assortatively. They established a stock population of D. melanogaster with flies collected in an orchard near Davis, California. Pupae from the culture were placed into a habitat maze. Newly emerged flies had to negotiate the maze to find food. The maze simulated several environmental gradients simultaneously. The flies had to make three choices of which way to go. The first was between light and dark (phototaxis). The second was between up and down (geotaxis). The last was between the scent of acetaldehyde and the scent of ethanol (chemotaxis). This divided the flies among eight habitats. The flies were further divided by the time of day of emergence. In total the flies were divided among 24 spatio-temporal habitats.
They next cultured two strains of flies that had chosen opposite habitats. One strain emerged early, flew upward and was attracted to dark and acetaldehyde. The other emerged late, flew downward and was attracted to light and ethanol. Pupae from these two strains were placed together in the maze. They were allowed to mate at the food site and were collected. Eye color differences between the strains allowed Rice and Salt to distinguish between the two strains. A selective penalty was imposed on flies that switched habitats. Females that switched habitats were destroyed. None of their gametes passed into the next generation. Males that switched habitats received no penalty. After 25 generations of this mating tests showed reproductive isolation between the two strains. Habitat specialization was also produced.
They next repeated the experiment without the penalty against habitat switching. The result was the same -- reproductive isolation was produced. They argued that a switching penalty is not necessary to produce reproductive isolation. Their results, they stated, show the possibility of sympatric speciation.
5.3.6 Isolation Produced as an Incidental Effect of Selection on several Drosophila species

In a series of experiments, del Solar (1966) derived positively and negatively geotactic and phototactic strains of D. pseudoobscura from the same population by running the flies through mazes. Flies from different strains were then introduced into mating chambers (10 males and 10 females from each strain). Matings were recorded. Statistically significant positive assortative mating was found.
In a separate series of experiments Dodd (1989) raised eight populations derived from a single population of D. Pseudoobscura on stressful media. Four populations were raised on a starch based medium, the other four were raised on a maltose based medium. The fly populations in both treatments took several months to get established, implying that they were under strong selection. Dodd found some evidence of genetic divergence between flies in the two treatments. He performed mate choice tests among experimental populations. He found statistically significant assortative mating between populations raised on different media, but no assortative mating among populations raised within the same medium regime. He argued that since there was no direct selection for reproductive isolation, the behavioral isolation results from a pleiotropic by-product to adaptation to the two media. Schluter and Nagel (1995) have argued that these results provide experimental support for the hypothesis of parallel speciation.
Less dramatic results were obtained by growing D. willistoni on media of different pH levels (de Oliveira and Cordeiro 1980). Mate choice tests after 26, 32, 52 and 69 generations of growth showed statistically significant assortative mating between some populations grown in different pH treatments. This ethological isolation did not always persist over time. They also found that some crosses made after 106 and 122 generations showed significant hybrid inferiority, but only when grown in acid medium.
5.3.7 Selection for Reinforcement in Drosophila melanogaster

Some proposed models of speciation rely on a process called reinforcement to complete the speciation process. Reinforcement occurs when to partially isolated allopatric populations come into contact. Lower relative fitness of hybrids between the two populations results in increased selection for isolating mechanisms. I should note that a recent review (Rice and Hostert 1993) argues that there is little experimental evidence to support reinforcement models. Two experiments in which the authors argue that their results provide support are discussed below.
Ehrman (1971) established strains of wild-type and mutant (black body) D. melanogaster. These flies were derived from compound autosome strains such that heterotypic matings would produce no progeny. The two strains were reared together in common fly cages. After two years, the isolation index generated from mate choice experiments had increased from 0.04 to 0.43, indicating the appearance of considerable assortative mating. After four years this index had risen to 0.64 (Ehrman 1973).
Along the same lines, Koopman (1950) was able to increase the degree of reproductive isolation between two partially isolated species, D. pseudoobscura and D. persimilis.
5.3.8 Tests of the Founder-flush Speciation Hypothesis Using Drosophila

The founder-flush (a.k.a. flush-crash) hypothesis posits that genetic drift and founder effects play a major role in speciation (Powell 1978). During a founder-flush cycle a new habitat is colonized by a small number of individuals (e.g. one inseminated female). The population rapidly expands (the flush phase). This is followed by the population crashing. During this crash period the population experiences strong genetic drift. The population undergoes another rapid expansion followed by another crash. This cycle repeats several times. Reproductive isolation is produced as a byproduct of genetic drift.
Dodd and Powell (1985) tested this hypothesis using D. pseudoobscura. A large, heterogeneous population was allowed to grow rapidly in a very large population cage. Twelve experimental populations were derived from this population from single pair matings. These populations were allowed to flush. Fourteen months later, mating tests were performed among the twelve populations. No postmating isolation was seen. One cross showed strong behavioral isolation. The populations underwent three more flush-crash cycles. Forty-four months after the start of the experiment (and fifteen months after the last flush) the populations were again tested. Once again, no postmating isolation was seen. Three populations showed behavioral isolation in the form of positive assortative mating. Later tests between 1980 and 1984 showed that the isolation persisted, though it was weaker in some cases.
Galina, et al. (1993) performed similar experiments with D. pseudoobscura. Mating tests between populations that underwent flush-crash cycles and their ancestral populations showed 8 cases of positive assortative mating out of 118 crosses. They also showed 5 cases of negative assortative mating (i.e. the flies preferred to mate with flies of the other strain). Tests among the founder-flush populations showed 36 cases of positive assortative mating out of 370 crosses. These tests also found 4 cases of negative assortative mating. Most of these mating preferences did not persist over time. Galina, et al. concluded that the founder-flush protocol yields reproductive isolation only as a rare and erratic event.
Ahearn (1980) applied the founder-flush protocol to D. silvestris. Flies from a line of this species underwent several flush-crash cycles. They were tested in mate choice experiments against flies from a continuously large population. Female flies from both strains preferred to mate with males from the large population. Females from the large population would not mate with males from the founder flush population. An asymmetric reproductive isolation was produced.
In a three year experiment, Ringo, et al. (1985) compared the effects of a founder-flush protocol to the effects of selection on various traits. A large population of D. simulans was created from flies from 69 wild caught stocks from several locations. Founder-flush lines and selection lines were derived from this population. The founder-flush lines went through six flush-crash cycles. The selection lines experienced equal intensities of selection for various traits. Mating test were performed between strains within a treatment and between treatment strains and the source population. Crosses were also checked for postmating isolation. In the selection lines, 10 out of 216 crosses showed positive assortative mating (2 crosses showed negative assortative mating). They also found that 25 out of 216 crosses showed postmating isolation. Of these, 9 cases involved crosses with the source population. In the founder-flush lines 12 out of 216 crosses showed positive assortative mating (3 crosses showed negative assortative mating). Postmating isolation was found in 15 out of 216 crosses, 11 involving the source population. They concluded that only weak isolation was found and that there was little difference between the effects of natural selection and the effects of genetic drift.
A final test of the founder-flush hypothesis will be described with the housefly cases below.
5.4 Housefly Speciation Experiments



5.4.1 A Test of the Founder-flush Hypothesis Using Houseflies

Meffert and Bryant (1991) used houseflies to test whether bottlenecks in populations can cause permanent alterations in courtship behavior that lead to premating isolation. They collected over 100 flies of each sex from a landfill near Alvin, Texas. These were used to initiate an ancestral population. From this ancestral population they established six lines. Two of these lines were started with one pair of flies, two lines were started with four pairs of flies and two lines were started with sixteen pairs of flies. These populations were flushed to about 2,000 flies each. They then went through five bottlenecks followed by flushes. This took 35 generations. Mate choice tests were performed. One case of positive assortative mating was found. One case of negative assortative mating was also found.
5.4.2 Selection for Geotaxis with and without Gene Flow

Soans, et al. (1974) used houseflies to test Pimentel's model of speciation. This model posits that speciation requires two steps. The first is the formation of races in subpopulations. This is followed by the establishment of reproductive isolation. Houseflies were subjected to intense divergent selection on the basis of positive and negative geotaxis. In some treatments no gene flow was allowed, while in others there was 30% gene flow. Selection was imposed by placing 1000 flies into the center of a 108 cm vertical tube. The first 50 flies that reached the top and the first 50 flies that reached the bottom were used to found positively and negatively geotactic populations. Four populations were established:
Population A + geotaxis, no gene flow Population B - geotaxis, no gene flow Population C + geotaxis, 30% gene flow Population D - geotaxis, 30% gene flow Selection was repeated within these populations each generations. After 38 generations the time to collect 50 flies had dropped from 6 hours to 2 hours in Pop A, from 4 hours to 4 minutes in Pop B, from 6 hours to 2 hours in Pop C and from 4 hours to 45 minutes in Pop D. Mate choice tests were performed. Positive assortative mating was found in all crosses. They concluded that reproductive isolation occurred under both allopatric and sympatric conditions when very strong selection was present.
Hurd and Eisenberg (1975) performed a similar experiment on houseflies using 50% gene flow and got the same results.
5.5 Speciation Through Host Race Differentiation

Recently there has been a lot of interest in whether the differentiation of an herbivorous or parasitic species into races living on different hosts can lead to sympatric speciation. It has been argued that in animals that mate on (or in) their preferred hosts, positive assortative mating is an inevitable byproduct of habitat selection (Rice 1985; Barton, et al. 1988). This would suggest that differentiated host races may represent incipient species.
5.5.1 Apple Maggot Fly (Rhagoletis pomonella)

Rhagoletis pomonella is a fly that is native to North America. Its normal host is the hawthorn tree. Sometime during the nineteenth century it began to infest apple trees. Since then it has begun to infest cherries, roses, pears and possibly other members of the rosaceae. Quite a bit of work has been done on the differences between flies infesting hawthorn and flies infesting apple. There appear to be differences in host preferences among populations. Offspring of females collected from on of these two hosts are more likely to select that host for oviposition (Prokopy et al. 1988). Genetic differences between flies on these two hosts have been found at 6 out of 13 allozyme loci (Feder et al. 1988, see also McPheron et al. 1988). Laboratory studies have shown an asynchrony in emergence time of adults between these two host races (Smith 1988). Flies from apple trees take about 40 days to mature, whereas flies from hawthorn trees take 54-60 days to mature. This makes sense when we consider that hawthorn fruit tends to mature later in the season that apples. Hybridization studies show that host preferences are inherited, but give no evidence of barriers to mating. This is a very exciting case. It may represent the early stages of a sympatric speciation event (considering the dispersal of R. pomonella to other plants it may even represent the beginning of an adaptive radiation). It is important to note that some of the leading researchers on this question are urging caution in interpreting it. Feder and Bush (1989) stated:
[INDENT] "Hawthorn and apple "host races" of R. pomonella may therefore represent incipient species. However, it remains to be seen whether host-associated traits can evolve into effective enough barriers to gene flow to result eventually in the complete reproductive isolation of R. pomonella populations."
[/INDENT] 5.5.2 Gall Former Fly (Eurosta solidaginis)

Eurosta solidaginis is a gall forming fly that is associated with goldenrod plants. It has two hosts: over most of its range it lays its eggs in Solidago altissima, but in some areas it uses S. gigantea as its host. Recent electrophoretic work has shown that the genetic distances among flies from different sympatric hosts species are greater than the distances among flies on the same host in different geographic areas (Waring et al. 1990). This same study also found reduced variability in flies on S. gigantea. This suggests that some E. solidaginis have recently shifted hosts to this species. A recent study has compared reproductive behavior of the flies associated with the two hosts (Craig et al. 1993). They found that flies associated with S. gigantea emerge earlier in the season than flies associated with S. altissima. In host choice experiments, each fly strain ovipunctured its own host much more frequently than the other host. Craig et al. (1993) also performed several mating experiments. When no host was present and females mated with males from either strain, if males from only one strain were present. When males of both strains were present, statistically significant positive assortative mating was seen. In the presence of a host, assortative mating was also seen. When both hosts and flies from both populations were present, females waited on the buds of the host that they are normally associated with. The males fly to the host to mate. Like the Rhagoletis case above, this may represent the beginning of a sympatric speciation.
5.6 Flour Beetles (Tribolium castaneum)

Halliburton and Gall (1981) established a population of flour beetles collected in Davis, California. In each generation they selected the 8 lightest and the 8 heaviest pupae of each sex. When these 32 beetles had emerged, they were placed together and allowed to mate for 24 hours. Eggs were collected for 48 hours. The pupae that developed from these eggs were weighed at 19 days. This was repeated for 15 generations. The results of mate choice tests between heavy and light beetles was compared to tests among control lines derived from randomly chosen pupae. Positive assortative mating on the basis of size was found in 2 out of 4 experimental lines.
5.7 Speciation in a Lab Rat Worm, Nereis acuminata5.8 Speciation Through Cytoplasmic Incompatability Resulting from the Presence of a Parasite or Symbiont

In some species the presence of intracellular bacterial parasites (or symbionts) is associated with postmating isolation. This results from a cytoplasmic incompatability between gametes from strains that have the parasite (or symbiont) and stains that don't. An example of this is seen in the mosquito Culex pipiens (Yen and Barr 1971). Compared to within strain matings, matings between strains from different geographic regions may may have any of three results: These matings may produce a normal number of offspring, they may produce a reduced number of offspring or they may produce no offspring. Reciprocal crosses may give the same or different results. In an incompatible cross, the egg and sperm nuclei fail to unite during fertilization. The egg dies during embryogenesis. In some of these strains, Yen and Barr (1971) found substantial numbers of Rickettsia-like microbes in adults, eggs and embryos. Compatibility of mosquito strains seems to be correlated with the strain of the microbe present. Mosquitoes that carry different strains of the microbe exhibit cytoplasmic incompatibility; those that carry the same strain of microbe are interfertile.
Similar phenomena have been seen in a number of other insects. Microoganisms are seen in the eggs of both Nasonia vitripennis and N. giraulti. These two species do not normally hybridize. Following treatment with antibiotics, hybrids occur between them (Breeuwer and Werren 1990). In this case, the symbiont is associated with improper condensation of host chromosomes.
For more examples and a critical review of this topic, see Thompson 1987.
5.9 A Couple of Ambiguous Cases

So far the BSC has applied to all of the experiments discussed. The following are a couple of major morphological changes produced in asexual species. Do these represent speciation events? The answer depends on how species is defined.
5.9.1 Coloniality in Chlorella vulgaris

Boraas (1983) reported the induction of multicellularity in a strain of Chlorella pyrenoidosa (since reclassified as C. vulgaris) by predation. He was growing the unicellular green alga in the first stage of a two stage continuous culture system as for food for a flagellate predator, Ochromonas sp., that was growing in the second stage. Due to the failure of a pump, flagellates washed back into the first stage. Within five days a colonial form of the Chlorella appeared. It rapidly came to dominate the culture. The colony size ranged from 4 cells to 32 cells. Eventually it stabilized at 8 cells. This colonial form has persisted in culture for about a decade. The new form has been keyed out using a number of algal taxonomic keys. They key out now as being in the genus Coelosphaerium, which is in a different family from Chlorella.
5.9.2 Morphological Changes in Bacteria

Shikano, et al. (1990) reported that an unidentified bacterium underwent a major morphological change when grown in the presence of a ciliate predator. This bacterium's normal morphology is a short (1.5 um) rod. After 8 - 10 weeks of growing with the predator it assumed the form of long (20 um) cells. These cells have no cross walls. Filaments of this type have also been produced under circumstances similar to Boraas' induction of multicellularity in Chlorella. Microscopic examination of these filaments is described in Gillott et al. (1993). Multicellularity has also been produced in unicellular bacterial by predation (Nakajima and Kurihara 1994). In this study, growth in the presence of protozoal grazers resulted in the production of chains of bacterial cells.[/indent]



Wrong.



humans are animals

lrn2biology



and there's nothing wrong with that

Okey, here's the deal. You can't possibly know what an animal or plant is going to evolve to. Just because reptiles has becomed bird in the past doesn't mean that they are on their way to evolving back. In a million years seals might walk on land. I don't know. You can't see species' evolution when you're in the middle of it. But we can see the bacterias evolution and so on.


Okey, look down. Take a good look at your toes. They have toenails. Would God have created those?:nonooo: I rest my case.

Henry Gee, chief science writer for Nature:

Gee wrote in 1999: "To take a line of fossils and claim that they represent a lineage is not a scientific hypothesis that can be tested, but an assertion that carries the same validity as a bedtime story--amusing, perhaps even instructive, but not scientific."


Jerry Coyne, an evolutionary biologist at the University of Chicago, has written that "evolutionary psychologists routinely confuse theory and speculation"....."By judicious manipulation, every possible observation of human behavior could be (and was) fitted into a Freudian framework. The same trick is now being perpetrated by the evolutionary psychologists. They, too, deal with their own dogmas, and not in propositions of science."

ScienceDaily (Dec. 16, 2005) - Biologists at Georgia Tech have provided scientific support for a controversial hypothesis that has divided the fields of evolutionary genomics and evolutionary developmental biology, popularly known as evo devo, for two years. Appearing in the December 2005 issue of Trends in Genetics, researchers find that the size and complexity of a species' genome is not an evolutionary adaptation per se, but can result as simply a consequence of a reduction in a species' effective population size.


"Evolutionism is a fairy tale for grown-ups. This theory has helped nothing in the progress of science. It is useless," says Professor Louis Bouroune, former President of the Biological Society of Strasbourg and Director of the Strasbourg Zoological Museum, later Director of Research at the French National Centre of Scientific Research, as quoted in The Advocate, March 8, 1984.


"Scientists who go about teaching that evolution is a fact of life are great con-men, and the story they are telling may be the greatest hoax ever. In explaining evolution we do not have one iota of fact." (Dr. T.N. Tahmisian. Atomic Energy Commission, The Fresno Bee, August 20, 1959.

...most people assume that fossils provide a very important part of the general argument made in favor of Darwinian interpretation of the history of life. Unfortunately, this is not strictly true." (Dr. David Raup, Curator, Field Museum of Natural History, Chicago. Quoted from "Conflicts between Darwin and paleontology," Field Museum of Natural History Bulletin, Vol. 50 (1), 1979.)

"...I fully agree with your comments on the lack of direct illustration of evolutionary transition in my book. If I knew of any, fossil or living, I would certainly have included them...Yet Gould and the American Museum people are hard to contradict when they say there are no transitional fossils...I will lay it on the line--there is not one such fossil for which one could make a watertight argument." (Personal letter from Dr. Colin Patterson, Senior Paleontologist at the British Museum of Natural History in London, to L. Sunderland.)


"Despite the bright promise that paleontology provides a means of 'seeing' evolution, it has presented some nasty difficulties for evolutionists, the most notorious of which is the presence of 'gaps' in the fossil record. Evolution requires intermediate forms between species and paleontology does not provide them..." (David B. Kitts, Ph.D. -- Zoology, Head Curator, Department of Geology, Stoval Museum, and well-known evolutionary paleontologist. Evolution, Vol. 28, Sept. 1974.

Should the thoughts and speculations of these learned people be so easily cast aside?

So you don't belive in DNA? You can't see the differrence between the wild raspberries and the ones in your garden?
If you are making a jigsaw, and there are some pieces missing, would it really be impossible to see the image?

Gee is an evolutionary biologist and you're quote-mining from him:

Sunbeams From Cucumbers: Wittlessly Quote-mining



oh hey look another evolutionary biologist

he's disputing claims made by evolutionary psychologists, not the theory of evolution itself, try to pay attention



and this challenges the central tenets of Darwinian evolution ... how?



oh hey more mindless out-of-context quote mining

Cretinism or Evilution?: More Out of Context Quotations of French Scientists



for all I know this is out-of-context too but it doesn't matter because this guy was a nuclear physicist, not a biologist



also taken out of context

The Challenge of the Fossil Record



out of context again

Patterson Misquoted: A Tale of Two 'Cites'



hey! more quote mining

Quote Mine Project: "Lack of Identifiable Phylogeny"

don't think parroting out-of-context quotes impresses me



yes, when they're taken out of context, when they're made by people who are talking out of their area of expertise, when their views are a tiny tiny tiny minority in a vast ocean of experts which equal or better qualifications who say otherwise

you go on and on about how I'm "casting aside" the thoughts of "learned people" ... but the 99.9% of biologists who take stock in evolution: what about them? are their thoughts to be cast aside lightly? or do the the 0.1% of dissenters carry more weight than everyone else?

do I have to entertain Aristotelian physics just because Aristotle was smart? no

do I have to entertain creationism just because one nuclear physicist from the fifties appears to have supported it? no

---------- Post added 08-25-2009 at 11:47 AM ----------

oh hey check this out

A misleading and deceptive articlenot argue that there aren't any transitional fossils. This is such a lie, and Gould wrote one whole essay on the transitional forms of whales that have been found which is entitled "Hooking Leviathan by Its Past," which can be read in his book Dinosaur in a Haystack, on pages 359-376. Let me quote a little bit of what he has to say:[INDENT]"We can trace, through a lovely sequence of intermediates, the reduction of these small reptilian bones, and their eventual disappearance or exclusion from the jaw, including the remarkable passage of the reptilian articulation bones into the mammalian middle ear (Where they have become our malleus and incus, or hammer and anvil). We have even found the transitional form that creationists often proclaim inconceivable in theoryallthe one citing this letter (which conveniently can't be verified, can I check out this letter at the library and read it?) is a liar or an ignorant fool, one or the other. If I were him, I'd check with Gould before I tried to represent him.

We see genetic and corresponding phenotypic change in direct response to a targeted selective pressure. THAT is evolution. For things with short generation time, like microorganisms, you can observe evolution in a lab experiment.

http://en.wikipedia.org/wiki/Australopithecus;

Happens to be extinct, but its fossil dating corresponds very closely to what we would expect based on the DNA homology between chimps and humans. It lived around 2-3 million years ago, and humans shared a common ancestor with modern chimps around 5 million years ago. It was a bipedal, upright walking great ape.

We all are -- the problem is that without being able to tell the future, it makes no sense to look at currently living species as "missing links".

I like this. The only thing we can ever know is that we can know nothing. I can absolutely see some theories being more "probable" than others... but nothing is certain. Except that, in a universe that many believe to be infinite, probability doesn't seem very relevant.

They are talking outside their field of study. Would you listen to an engineer about evolution or a biologist?



That is probably where the confusion comes from because you think 'fact' means something different than its scientific purpose. Youre confusing terminology.




How bout a crockoduck?








They are everywhere. The fossil record has numerous transitional species. Heres the famous Tiktaalik:






Your definition of the word 'fact' is what is confusing you.

That is why I made THIS thread.

Yes, you are correct.

Keep in mind, however, that the scientific understanding of evolution is a conglomerate of mutually corroborative sciences, and the development of molecular genetics is undoubtedly the most important.

Why?

Because Darwin's observation lacked a mechanism. With molecular genetics, the actual mechanism behind phenotypic evolution came to light.

Genetic molecules and mechanisms are remarkably similar across eukaryotes, i.e. everything from protozoa to plants to humans, and even among bacteria and viruses it's sufficiently similar.

So on a brief time scale we can easily demonstrate evolution happening prospectively. Based on differential genetic homology, we can easily demonstrate common ancestry. And based on gene conservation, we can even get pretty good estimates of the timeline of evolutionary divergence -- and these estimates corroborate the fossil record.

And while the evolution of viruses like HIV may not directly speak to human evolution, the point is that in real life we get a constant proof-of-principle when we can see evolution happening on a day-to-day time scale.

I would be interested to know why you think we cannot make reasonable inferences about the distant past. Is it the lack of eyewitnesses that is the problem, or just the sheer length of time?

Criminals are often convicted solely on the basis of very strong circumstantial evidence; the jury finds them guilty beyond reasonable doubt despite the fact that nobody actually saw the crime being committed. So the lack of eyewitnesses need not prevent a confident inference from being made.

I accept that the greater the length of time since the alleged event or process, the better the evidence we need. But this is only a matter of degree; if the evidence is strong enough, I do not see why we cannot accept it beyond reasonable doubt. And in the case of Darwinian evolution (biological evolution driven largely by (non-random) natural selection working on random mutations) the evidence is overwhelming - see for example Oden's post #11.

You say that "anything could have happened" so long ago. But what, other than evolution, could have happened, given the observations of the fossil record, molecular genetics etc? Did God or the Devil cunningly place all the fossils in exactly the right strata of rock so as to deceive us?

stay on topic, and try to do it without unnecessary offensiveness, whether you mean to offend or not