Oh, dear, more canards in need of the relevant ordnance.

Let's take a look at this shall we?

there is zero proof that life can ever start from Non life.

Actually, if you bother to survey the relevant literature, scientists have established that all the chemical reactions thus far postulated to be implicated in the origin of life work. There's a large body of experimental evidence to this effect. Everything from the synthesis of amino acids and nucleotides upwards has been investigated in the laboratory by people such as Jack Szostak and Leslie Orgel, and the relevant chemical reactions all work under prebiotic conditions.

The Emergence Of Life On Earth

In the earliest period of the history of the planet, it was a body devoid of life, and conditions on the planet were far from conducive to the appearance of life, particularly during the episode termed "The Late Heavy Bombardment" [1] by scientists, which saw intense bolide impact activity taking place on the planet's surface. Once this episode, and subsequent episodes postulated to have taken place, were complete, the Earth cooled, a solid crust formed, and liquid water in quantity began to appear. Thus, the stage was set for the processes that were to result in the emergence of life.

It was Darwin himself who first speculated about the origins of life, with his short remarks about a "warm little pond" [2], but, in the middle of the 19th century, this would remain speculation, as the means to determine the mechanisms that might apply had not yet been developed. However, it made eminent sense to scientists following Darwin, to hypothesise that any natural mechanisms responsible for the origin of life would be based upon organic chemistry, since life itself is manifestly based thereupon - millions of organic reactions are taking place within your body as you read this, and indeed, the cessation of some of those reactions constitutes the end of life for any organisms affected. Alexander Oparin, the Soviet biochemist, was the first to publish hypotheses about the chemical basis of the origin of life [3], and based his own hypotheses on the notion that a reducing atmosphere existed on the primordial Earth, facilitating the production of various organic compounds that would then react further, producing a cascade of escalating complexity that would ultimately result in self-replicating entities. Back in 1924, his hypotheses remained beyond the remit of scientists to test, but that would soon change.

The first indications that Oparin had alighted upon workable ideas came in 1953, with the celebrated Miller-Urey Experiment [4], in which electrical discharges in a reducing atmosphere composed of simple molecules produced measurable quantities of amino acids. Miller himself only cited the presence of five amino acids, as he was reliant at the time upon paper chromatography as his primary analytical tool, which was only sensitive enough to detect those five amino acids cited. However, Miller had been more successful than he originally claimed: after his death, preserved samples of his original reaction mixtures were subject to state-of-the-art analysis, using gas chromatograph mass spectrometry, a technique millions of times more sensitive, and regarded as the 'gold standard' in modern organic analysis. That subsequent analysis yielded not five, but twenty-two amino acids [5].

Early criticism of Miller's work in the scientific community focused upon the requirement for a reducing atmosphere in accordance with the Oparin model. However, subsequent workers determined by repeat experimentation, that a range of atmospheric constitutions would be suitable for a Miller-Urey type synthesis on a prebiotic Earth [6], several of those constitutions being only mildly reducing, expanding the range of conditions for which the Oparin model would be viable. More recently, work has suggested that the prebiotic Earth could have developed an atmosphere containing considerably more hydrogen than originally thought [7], making the Oparin reducing atmosphere once again more plausible. Indeed, the range of conditions under which amino acids could be synthesised has since been expanded to include interstellar ice clouds, courtesy of more recent research [8 - 14], and the Murchison meteorite was found to contain no less than ninety amino acids, nineteen of which are found on Earth, which were obviously synthesised whilst that meteorite was still in space. Other data from meteorites adds to this body of evidence [10, 15, 16].

The formation of amino acids itself, whilst an important step in any naturalistic origin of life, would need to be accompanied by some means of linking those amino acids into peptide molecules [17] - the process by which proteins are formed. A significant step forward with respect to this, arose when researchers alighted upon the fact that carbonyl sulphide, a gas that is produced in quantity naturally by volcanoes, acts as a catalyst for the formation of peptides, increasing yields dramatically [18]. This would facilitate peptide formation not only in the vicinity of hydrothermal vents, but in the vicinity of terrestrial volcanoes close to bodies of open water. Indeed, Miller had produced the 22 amino acids found in some of his reaction mixtures by extending the synthesis to include volcanic input, though not carbonyl sulphide - the addition of carbonyl sulphide would, however, facilitate peptide formation rapidly once the amino acids themselves were formed.

One additional problem to be overcome was the 'chirality problem'. Amino acids, with the exception of glycine, are chiral molecules, existing in two forms that are mirror images of each other in space (stereoisomers). Initially, methods for producing one form preferentially over another were something of a puzzle, but chemists working in an entirely different field established that a process called 'chiral catalysis' exists, indeed, this work led to a Nobel Prize for the researchers in question [19]. The demonstrated existence of working chiral catalysts [20] led abiogenesis researchers to seek such catalytic processes in their own field, and, in due course, these were alighted upon [15, 21- 24].

However, amino acids are not the only molecules required for life, important though they are. Some form of self-replicating molecule, providing the basis of an inheritance mechanism, is required. Given the difficulties involved in synthesising DNA as a total synthesis, researchers turned to RNA instead, a molecule that still forms the basis of the genomes of numerous extant taxonomic Families of viruses today. RNA, being easier to synthesise, was considered a natural first choice for the basis of primordial genomes, and thus, attention turned to the synthesis of RNA under prebiotic conditions. This was soon found not only to be possible, but to be readily achievable in the laboratory, and indeed, catalysis plays a role in these experiments. Natural clays formed from a mineral called montmorillonite provide a ready natural catalyst that would have been present in quantity on a prebiotic Earth, and the catalytic chemistry of RNA formation whilst adsorbed to such clays is now a standard part of the scientific literature [22- 42].

Having established that RNA was synthesisable under prebiotic conditions, researchers then turned to the matter of establishing the existence of self-replicating species of RNA molecules. This was duly successful [30, 43, 45 - 47], establishing that such species could have arisen among the extant RNA molecules being synthesised on a prebiotic Earth, and of course, once one self-replicating species exists, the process of evolution can begin, which has also since been demonstrated to apply to replicating RNAs in appropriate laboratory experiments [48].

Once a self-replicating molecule that can form the basis of an inheritance mechanism exists, the next stage scientists postulate to be required is encapsulation within some sort of selectively permeable membrane. The molecules of choice for these membrane are lipids, which have been demonstrated repeatedly in the laboratory to undergo spontaneous self-organisation into various structures, such as bilayer sheets, micelles and liposomes. Indeed, in the case of phospholipids, they can be stimulated to self-organise by the simple process of agitating the solution within which they are suspended - literally, shake the bottle [49 - 53]. Moreover, research has established that these lipids can encapsulate RNA molecules, and selectively admit the passage of base and sugar molecules to facilitate RNA replication [54, 55]. With the advent of this discovery in appropriate laboratory research, protocell formation is but a short step away, and indeed, the latest research is now actively concentrating upon the minimum components required in order for a viable, self-replicating protocell to exist. Prebiotic lipid formation is also a part of the repertoire of the literature in the field, and some papers now extant document the first experiments aimed at producing viable self-replicating protocells [55 - 70].

Whilst scientists naturally accept that 'joining the dots' between these individual steps is entirely proper, particularly on a body the size of a planet over a 100 million year period, the absence of experiments actively coupling these stages is a matter remaining to be addressed, though such experiments will be ambitious in scope indeed if they are to produce complete working protocells at the end of a long production line starting with a Miller-Urey synthesis. A 'grand synthesis' of this sort in the laboratory is not high on the scientific agenda at the moment, which is more concerned with validating the individual hypothesised steps, but once those steps are accepted as valid in the field, doubtless one day a 'grand synthesis' will be attempted, and the success thereof will establish beyond serious doubt that our pale blue dot became our home courtesy of well-defined and testable chemical reactions. Even so, no one conversant with the literature seriously considers any more that magical forces are required to produce life: just as vitalism was refuted by Wöhler's classic experiment, that gave rise to organic chemistry as an empirical science in the first place, so it is likely to be rendered ever more irrelevant in abiogenesis research, as the steps leading to life's blossoming on our planet are traversed and studied in ever greater detail.

References:

[1] An apposite paper (among many) covering the Late Heavy Bombardment is:

Origin Of The Cataclysmic Late Heavy Bombardment Period Of The Terrestrial Planets by R. Gomes, H. F. Levison, K. Tsiganis and A. Morbidelli, Nature, 435: 466-469 (26th May 2005)

[2] Cited in The Life And Letters Of Charles Darwin, Including An Autobiographical Chapter, edited by Francis Darwin, 1887

[3] The Origin And Development Of Life by Alexander Oparin, 1924 (English translation: NASA TTF-488)

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[5] The Miller Volcanic Discharge Spark Experiment by Adam P. Johnson, H. James Cleaves, Jason P. Dworkin, Daniel P. Glavin, Antonio Lazcano and Jeffrey L. Bada, Science, 322:404 (17th Ocotber 2008)

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[19] Nobel Prize for Chemistry, 2001, was awarded to William S. Knowles, Ryoji Noyori and K. Barry Sharpless, for their work establishing the existence of asymmetric catalysts and chiral catalysis - see the Nobel Lecture by William S. Knowles here

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Moving on ...

There is zero proof that a self replicating organisms can evolve into two sexes.

Oh, by the way, other forms of sexual differentiation exist in present day living organisms that point to the likely origin of sexual differentiation in the past. You are now going to learn everything you never wanted to know about yeast sex, but were forced to find out. :mrgreen:

Yeast mating is actually rather interesting. To cover this, we need to go over some background information first.

Yeast cells can exist in two major forms, a haploid form (which can undergo mitosis and produce two daughter cells), and a diploid form (which can undergo meiosis during times of stress, and produce four haploid daughter cells). The haploid cells are the ones that can mate, and when haploid mating occurs, the participant mating cells fuse to form a stable diploid cell. Diploid cells can also undergo mitosis, producing two diploid daughters.

Now, in order to understand haploid mating, we need to look at the genes and how they affect the process. First, we need to locate a special locus on chromosome 3 called MAT. There are two alleles present on this locus, called MATa and MATα, for reasons I don't understand. These loci differentiate the cells into two types, a cells and α cells. Next, we need to locate two other loci on the same chromosome, called HML (Hidden MAT Left) and HMR (Hidden Mat Right). HML contains a silenced copy of the MATα allele, and HMR contains a silenced copy of the MATa allele. The names refer to their position relative to the MAT locus itself. Laying chromosome 3 out so that its short arms are to the left of the centromere, and the long arms to the right, HML is on the short arm, then MAT is on the long arm relatively close to the centromere, and HMR is on the long arm further away from the centromere. So, in effect, both a and α cells contain a copy of the MATa and MATα allele, but these copies are silenced. These come into play later. The active locus is the MAT locus itself, and this locus contains one of the two alleles, MATa or MATα.

Additionally, there is a separate gene called HO, which is activated specifically only in haploid cells, and which only then during the G1 phase of the cell cycle (the phase during which the cell absorbs nutrients and grows). It affects the identity of the cells, though the precise mechanism has yet to be fully elucidated. More on this later.

Now, let's return to the MAT locus. This contains either a MATa allele, or a MATα allele. These alleles contain two genes, viz:

MATa : contains genes a1 and a2

MATα : contains genes α1 and α2

These genes are the master control genes for a transcription sequence, involving some downstream regulation, whose ultimate products are a cell surface receptor and a substance released into the environment that can be thought of as a 'pheromone' of sorts. As you might guess at this stage, the 'pheromone' associated with the MATa genes is called a-factor, whilst that associated with the MATα genes is called α-factor. The cell receptors are named according to a different convention though - the cell surface receptor generated by the MATa genes is called the ste2 receptor, and the receptor generated by the MATα genes is called the ste3 receptor.

Basically, what happens is this. An a cell and an α cell, in close proximity and in condition for mating, release their respective 'pheromones'. When the ste2 receptor of the a cell detects the presence of α-factor, the a cell grows a projection in the direction of highest concentration of α-factor. Likewise, when the ste3 receptor of the α cell detects a-factor, the α cell grows a projection in the direction of highest concentration of a-factor. These two projections eventually meet, whereupon the two cells undergo fusion and become a diploid cell. This diploid cell has two sets of the 16 chromosomes of a haploid yeast cell, one with the MATa genes on its copy of chromosome 3, the other with the MATα genes on its copy of chromosome 3.

Now here's the clever bit. A cell that only has one copy of the MAT genes allows the HO gene to be active in those cells, whilst a cell with two copies (a diploid cell) suppresses the HO gene. The reverse is true for genes that are activated by diploid cells, such as IME1, but this is irrelevant here: it's included simply in order to alert the reader wishing to pursue yeast genetics further that some genes are haploid-active only, and some diploid-active only. Suppression of HO allows both diploid mitosis to take place, or meiosis to produce four haploid daughters under conditions of stress.

So, what happens to haploid cells between mitotic divisions? This is where HO, and those two silenced loci HML and HMR, come into their own. During the G1 phase of the cell cycle, HO becomes active, generates a DNA endonuclease that cleaves the DNA at the MAT locus, wherupon exonuclease enzymes are attracted to the site and degrade the DNA there. Now here's the crunch: having effectively deleted its active MAT genes, the haploid cell now copies one of the silent copies back into the MAT locus. The clever part is this: if the cell began as an a cell, it copies the silenced copy from the HML locus, and in doing so switches identity to that of an α cell. Likewise, an α cell, when it deletes its MAT genes, copies the contents of the HMR locus to the MAT locus, and thus undergoes an identity switch to an a cell. Why this happens is a part of the mating system that isn't fully understood, but it happens, and so, in between mitotic divisions, an a cell switches to become an α cell and vice versa. Thus, even if a yeast population is founded in a new location entirely from haploid cells of one type, that population can generate cells of the other type, and the now mixed population of cells can mate, produce diploid cells, and set about increasing the genetic variation within the new founder population via meiosis. Very clever, is it not?

Now it turns out that scientists can manipulate this system. Deletion of one of the copies of the MAT locus in a diploid cell will cause that cell to exhibit haploid behaviour, and the HO gene will be activated, resulting in type switching of the remaining undeleted MAT locus after each diploid mitosis. Addition of an extra active MAT locus to a haploid cell results in the cell exhibiting diploid behaviour, and suppressing the HO gene. This will prove fatal in times of stress, because the haploid cell will attempt to undergo meiosis, resulting in destruction of the cell.

In order to make the study of yeast genetics easier, scientists work with haploid strains that have had the HO gene knocked out, so that type switching never occurs, and such yeast cells cannot therefore produce the mixed populations required for mating and diploid formation.

Note that this form of sexual differentiation relies upon a small set of genes all lying on one chromosome, and does not rely upon separate sex chromosomes. These were a later development.

So, yeast cells acquired the ability to engage in sexual reproduction, using a simple antecedent system to the one seen in later organisms, and which is a candidate for a stepping stone to the later variations of sexual reproduction that emerged. The fun part being, of course, that yeasts only activate this sexual reproductive system when the HO gene is active - a gene whose activity differs between haploid and diploid life stages. Otherwise, yeasts reproduce asexually.

So yeasts acquired a facultative sexual reproduction mechanism, which is a candidate for the foundation upon which later, obligate sexual reproduction mechanisms were constructed. Indeed, the emergence of facultative sexual reproduction systems in various unicellular organisms occurred more than once - there are numerous unicellular organisms in existence, that reproduce asexually for the most part, but which can switch to a sexual reproduction mode in a manner akin to yeast cells. Diatoms are a classic example, and an example in which sexual reproduction emerged as a solution to the offspring size problem inherent in these organisms, courtesy of the asymmetrical outer integument and the differential inheritance thereof by offspring during mitosis. Another collection of organisms under investigation with respect to their interesting switch between asexual and sexual reproduction are the Choanoflagellates, though research into their reproductive biology is still somewhat in its infancy. A small number of Dinoflagellate species also exhibit a switch between asexual and sexual reproduction.

However, among the more interesting finds, is this one, covering a multicellular eukaryote:

PFRU, A Single Dominant Locus Regulates The Balance Between Sexual And Asexual Plant Reproduction In Cultivated Strawberry by Amèlia Gaston, Justine Perrotte, Estelle Lerceteau-Köhler, Mathieu Rousseau-Gueutin, Aurélie Petit, Michel Hernould, Christophe Rothan & Béatrice Denoyes, Journal of Experimental Botany, Volume 64, Issue 7, April 2013, Pages 1837–1848, https://doi.org/10.1093/jxb/ert047 [Full paper downloadable from here

In this paper, the authors establish experimentally that the switch between sexual and asexual reproduction in cultivated Strawberry plants is controlled by a single gene. Viz:

Abstract

Strawberry (Fragaria sp.) stands as an interesting model for studying flowering behaviour and its relationship with asexual plant reproduction in polycarpic perennial plants. Strawberry produces both inflorescences and stolons (also called runners), which are lateral stems growing at the soil surface and producing new clone plants. In this study, the flowering and runnering behaviour of two cultivated octoploid strawberry (Fragaria×ananassa Duch., 2n=8×=56) genotypes, a seasonal flowering genotype CF1116 and a perpetual flowering genotype Capitola, were studied along the growing season. The genetic bases of the perpetual flowering and runnering traits were investigated further using a pseudo full-sibling F1 population issued from a cross between these two genotypes. The results showed that a single major quantitative trait locus (QTL) named FaPFRU controlled both traits in the cultivated octoploid strawberry. This locus was not orthologous to the loci affecting perpetual flowering (SFL) and runnering (R) in Fragaria vesca, therefore suggesting different genetic control of perpetual flowering and runnering in the diploid and octoploid Fragaria spp. Furthermore, the FaPFRU QTL displayed opposite effects on flowering (positive effect) and on runnering (negative effect), indicating that both traits share common physiological control. These results suggest that this locus plays a major role in strawberry plant fitness by controlling the balance between sexual and asexual plant reproduction.

Oh look. Strawberry plants have a system switching between sexual and asexual reproduction, controlled by a single gene. And that is in a multicellular eukaryote to boot.

Moving on ...

There is no proof that macroevolutiom is possible.

This is complete poppycock. Speciation has not only been observed and documented on multiple occasions, but has been the subject of laboratory experiments. Perhaps the best example I can provide comes courtesy of this paper:

Speciation By Hybridisation In Heliconius Butterflies by Jesús Mavárez, Camilo A. Salazar, Eldredge Bermingham, Christian Salcedo, Chris D. Jiggins and Mauricio Linares, Nature, 441: 868-871 (15th June 2006) [Full paper downloadable from [url=http://si-pddr.si.edu/dspace/bitstream/10088/4131/1/Mavarez_Salazar_Berm...

Speciation is generally regarded to result from the splitting of a single lineage. An alternative is hybrid speciation, considered to be extremely rare, in which two distinct lineages contribute genes to a daughter species. Here we show that a hybrid trait in an animal species can directly cause reproductive isolation. The butterfly species Heliconius heurippa is known to have an intermediate morphology and a hybrid genome [1], and we have recreated its intermediate wing colour and pattern through laboratory crosses between H. melpomene, H. cydno and their F1 hybrids. We then used mate preference experiments to show that the phenotype of H. heurippa reproductively isolates it from both parental species. There is strong assortative mating between all three species, and in H. heurippa the wing pattern and colour elements derived from H. melpomene and H. cydno are both critical for mate recognition by males.

The authors continue with:

Homoploid hybrid speciation—hybridization without change in chromosome number—is considered very rare [2–4]. This has been explained by the theoretical prediction that reproductive isolation between hybrids and their parents is difficult to achieve [3,5,6]. However, if a hybrid phenotype directly causes reproductive isolation from parental taxa, this difficulty can be overcome. Such a role for a hybrid phenotype has been convincingly demonstrated only in Helianthus sunflowers [7]. In animals, the evidence for homoploid hybrid speciation is less convincing. Putative hybrid species are known with mixed genomes [8–11], but in these examples shared genetic variation could also be a result of introgression subsequent to a bifurcating speciation event.

Heliconius cydno and H. melpomene are two closely related species that overlap extensively in lower Mesoamerica and the Andes [12]. Speciation in these butterflies has not involved any change in chromosome number [13] but is instead associated with shifts in colour patterns that generate both assortative mating and postzygotic isolation due to predator-mediated selection [14–17]. Heliconius cydno is black with white and yellow marks, whereas H. melpomene is black with red, yellow and orange marks. Both species exhibit strong positive assortative mating based on their wing colour patterns and also differ in habitat use [18] and host plant preference [19], but interspecific hybrids do occur at low frequency in the wild [15]. Heliconius heurippa has an intermediate wing pattern, which has led to the suggestion that this is a hybrid species [1,20]. Its hindwing is indistinguishable from that of sympatric H. m. melpomene, whereas the yellow band on its forewing is similar to that of parapatric H. cydno cordula. Ecologically, H. heurippa is most similar to H. cydno, which it replaces geographically in the eastern Andes of Colombia. Here we first establish that H. heurippa is currently genetically isolated from its putative parents and provide evidence that its genome is of hybrid origin. A Bayesian assignment analysis using 12 microsatellite loci scored in populations from Panama, Colombia and Venezuela divides H. cydno (n = 175), H. melpomene (n = 167) and H. heurippa (n = 46) individuals into three distinct clusters (Fig. 1). Hence, H. heurippa is genetically more differentiated than any geographic race sampled of either species. Moreover, analyses of polymorphism at two nuclear genes (Invected and Distal-less) show no allele sharing between H. cydno and H. melpomene, whereas the H. heurippa genome appears as an admixture, sharing allelic variation with both putative parental species (Supplementary Fig. 2, and C.S., C.D.J. and M.L., unpublished observations).

So, the authors begin by noting that the wing pattern of Heliconius heurippa is intermediate between that of local races of Heliconius melpomene and Heliconius cydno, and ask the question whether or not this is because Heliconius heurippa is a hybrid between individuals from those two races of Heliconius melpomene and Heliconius cydno. Suspicions that this might be the case were reinforced, when a genetic analysis demonstrated that certain genes present in Heliconius heurippa were admixtures of those found in Heliconius melpomene and Heliconius cydno, whilst the genes in question show NO such admixture in the other two species.

[SPECIAL NOTE: I alighted upon papers after writing the original version of this article, covering the intricacies of the invected and distal-less genes in butterfly wing pattern formation, and how these genes produce a Turing-type morphogenetic system. But I digress. Back to the Heliconius speciation paper!]

Moving on ...

To test the hypothesis of a hybrid origin for the H. heurippa colour pattern, we performed inter-specific crosses between H. cydno cordula and H. m. melpomene to reconstruct the steps of introgressive hybridization that could have given rise to H. heurippa. The colour pattern differences between H. m. melpomene and H. cydno cordula are determined largely by three co-dominant loci controlling the red and yellow bands on the forewing and the brown pincer-shaped mark on the ventral hindwing (see Fig. 2a) [21,22]. Most H. cydno × H. melpomene F1 hybrids seem intermediate to both parents (Fig. 2a), with both a yellow (cydno) and a red (melpomene) band in the median section of the forewing, whereas the ventral side of the hindwing shows a reduced brown mark intermediate between the parental species.

So, the authors produced some experimental crosses, and noticed that those experimental crosses produced individuals possessing wing pattern intermediate between those of the parents. However, they didn't just produce single-generation crosses, instead, they tested the effects that would arise from multiple crossings across several generations, and the results were extremely illuminating to put it mildly! But I'm jumping the gun here a little ... let's see what the authors have to reveal to us, shall we?

Female F1 hybrids resulting from crosses between H. melpomene and H. cydno are sterile in accordance with Haldane’s rule [1,23], and thus only male F1 hybrids backcrossed to either H. cydno cordula or H. m. melpomene females resulted in offspring. Backcrosses to H. melpomene produced offspring very similar to pure H. m. melpomene, and further backcross generations never produced individuals with forewing phenotypes similar to H. heurippa (Fig. 2a). However, after only two generations a phenotype virtually identical to H. heurippa (Supplementary Fig. 3) was produced by backcrossing an F1 male to an H. cydno cordula female and then mating selected offspring of this cross (Fig. 2b). In offspring of crosses between these H. heurippa-like individuals the pattern breeds true, showing that they are homozygous for the red forewing band (BB) and the absence of brown hindwing marks (brbr) characteristic of H. melpomene, and similarly homozygous for the yellow forewing band (N-N N-N) derived from H. cydno. The pattern of these H. heurippa-like individuals also breeds true when crossed to wild H. heurippa (Fig. 2b), implying that pattern genes segregating in our crosses are homologous with those in wild H. heurippa.

Oh, now look at that for a spectacular set of results!

First of all, the authors crossed Heliconius melpomene with Heliconius cydno to produce F1 hybrids, then back-crossed the fertile males with females of each species. Back-crossing with Heliconius melpomene resulted in melpomene wing patterns reappearing, but back-crossing the F1 hybrids with Heliconius cydno to produce the F2 generation, then mating selected offspring of the F2 generation, produced individuals that were virtually identical to Heliconius heurippa!

But it gets even better. When the laboratory produced Heliconius heurippa analogues were mated to wild type Heliconius heurippa, they produced fertile offspring and the wing patterns bred true!.

These crossing experiments, as a consequence, constitute compellingly strong evidence that Heliconius heurippa resulted from a similar process occurring among hybrid butterflies in the wild. Not only did the authors reproduce the likely crossing sequence that produced Heliconius heurippa in the wild, thus providing a repeatable test of the relevant speciation mechanism, but the laboratory crosses were interfertile with the wild type Heliconius heurippa, further strengthening the hypothesis advanced by the authors.

Moving on ...

Furthermore, in a wild population of sympatric H. m. melpomene and H. cydno cordula in San Cristóbal, Venezuela, we observed natural hybrids at an unusually high frequency (8%), including some individuals very similar to our laboratory-produced H. heurippa-like butterflies (Fig. 2b). Microsatellite data show that these individuals have genotypes indistinguishable from that of H. cydno and must therefore be at least fifth-generation backcrosses (Supplementary Fig. 4). This shows that multiple generations of backcrossing can occur in the wild and that female hybrid sterility is not a complete barrier to introgressive hybridization. The fact that the H. heurippa pattern can be generated by laboratory crosses between H. melpomene and H. cydno, and is also observed in wild hybrids between the two species, establishes a probable natural route for the hybrid origin of H. heurippa.

Well, at this point, one is tempted to say, QED. The authors could hardly have asked for better, could they? Not only did their laboratory crosses reproduce virtually identical Heliconius heurippa analogues, that were furthermore interfertile with wild Heliconius heurippa, but they observed hybrids in the wild that included individuals matching both the wild type Heliconius heurippa and the authors' laboratory analogues!

Not satisfied with this, however, the authors then turned their attention to the next part of the speciation process, and performed some experiments to determine if an isolating mechanism was in place, which would reinforce speciation. Let's take a look at those experiments, shall we?

The next step in species formation is reproductive isolation. We therefore tested the degree to which H. heurippa is isolated from H. melpomene and H. cydno by assortative mating. No-choice mating experiments showed a reduced probability of mating in all interspecific comparisons, with H. heurippa females particularly unlikely to mate with either H. cydno or H. melpomene (Table 1). When a male of each species was presented with a single female, H. heurippa males were tenfold more likely to court their own females than the other species (Supplementary Fig. 5). In mating experiments with choice, there was similarly strong assortative mating, although occasional matings between H. cydno and H. heurippa were observed (Table 2). Isolation due to assortative mating, on average more than 90% between H. heurippa and H. melpomene and more than 75% between H. heurippa and H. cydno, is therefore considerably greater than that caused by hybrid sterility (about 25% isolation between H. heurippa and H. melpomene, and zero between H. heurippa and H. cydno) [1] or predator selection against hybrids (about 50%) [24]. Therefore, strong assortative mating, in combination with geographic isolation from H. cydno and postzygotic isolation from H. melpomene has contributed to the speciation of H. heurippa.

So, the females of the new species, Heliconius heurippa, exhibited strong preference for other male Heliconius heurippa, with probabilities of out-crossing being 0.073 with Heliconius melpomene males and 0.022 with Heliconius cydno males. Male Heliconius heurippa again exhibited strong preference for female Heliconius heurippa, with probabilities of outcrossing being 0.1 with Heliconius melponeme and 0.44 with Heliconius cydno females. The table in the paper also demonstrates that the parent species also show strong assortative mating, though exhibit enough tendency to hybridise with each other to produce the offspring needed to generate Heliconius heurippa in the first place (hybridisation rate approximately 8%).

However, apart from mating experiments, the authors conducted some other experiments too. Let's take a look at these shall we?

We next investigated the role of colour pattern in mate choice. Experiments with dissected wings showed that both elements of the forewing colour pattern of H. heurippa were necessary for the stimulation of courtship (Fig. 3). H. heurippa males were less than half as likely to approach and court the H. m. melpomene or the H. cydno cordula pattern than their own (Fig. 3).When either the red or yellow bands were experimentally removed from the H. heurippa pattern, this led to a similar reduction in its attractiveness, demonstrating that both hybrid elements are necessary for mate recognition by male H. heurippa (Fig. 3).

So in this experiment, the authors demonstrated that visual cues are important to Heliconius heurippa, and that experimental manipulation of the wing pattern to mask certain features reduces their attractiveness as visual stimuli to mating.

Similar results were obtained when these experiments were replicated with printed-paper models (Fig. 3), showing that the colour pattern itself was the cue rather than pheromones associated with the dissected wings. Additional experiments showed that males of both H. m. melpomene and H. cydno cordula showed a greatly reduced probability of approaching and courting the H. heurippa pattern than their own (Supplementary Figs 6 and 7). Given the incomplete postzygotic reproductive isolation between all three species [1], this pattern-based assortative mating must have a continuing role in generating reproductive isolation between H. heurippa and its relatives.

Nice. The above experiments established that visual stimuli reproduce the same pattern of assortative mating behaviour even in the absence of pheromones, demonstrating that visual cues are the primary means of stimulating courtship behaviour in these butterflies, and that those visual cues exert strong effects upon mate preference, leading to the assortative mating patterns seen above.

Novel patterns in Heliconius probably become established through a combination of genetic drift and subsequent fixation of the novel pattern driven by frequency-dependent selection [25]. Such an event could have established the hybrid H. heurippa pattern as a geographic isolate of H. cydno. Subsequently, the pattern was sufficiently distinct from both H. melpomene and H. cydno that mate-finding behaviour also diverged in parapatry, generating assortative mating between all three species (Supplementary Fig. 8). This two-stage process indicates a possible route by which the theoretical difficulty of a rapid establishment of reproductive isolation between the hybrid and the parental taxa could have been overcome [5,6]. Furthermore, because we are proposing divergence in mate behaviour in a geographically isolated population, reinforcement or some other form of sympatric divergence is not required for speciation to occur.

Our study provides the first experimental demonstration of a hybrid trait generating reproductive isolation between animal species, and the first example of a hybrid trait causing pre-mating isolation through assortative mating. None of the theoretical treatments of homoploid hybrid speciation have considered the effects of assortative mating[5,6]. If variation for mate preference were incorporated, the theoretical conditions favouring hybrid speciation might not be as stringent as has been supposed. Finally, two other species, H. pachinus [20] and H. timareta [26], have also been proposed as having H. cydno/H. melpomene hybrid patterns, indicating that this process might have occurred more than once. However, whether these cases represent a particularity of Heliconius or a common natural process that has been undetected in other animal groups studied less intensively remains a matter of further study. Suggestively, other proposed cases of homoploid hybrid speciation in animals occur in well-studied groups such as African cichlids [8–10] and Rhagoletis flies [11.

So, the authors were able to reproduce a wild speciation event in the laboratory, produce laboratory analogues of the new species that were interfertile with wild type members of that species, and demonstrate the existence of assortative mating preferences producing a reproductive isolation barrier between the new species and the parents once the new species existed. Furthermore, this mechanism of speciation has been erected as a probable model in other well-studied groups of organisms, including those particular favourites of mine among the vertebrates, African Cichlid fishes.

Game over for your assertion. That's before we take into account the literature covering speciation genes and observed instances of speciation. The following is a small sample of the available literature:

A Model For Divergent Allopatric Speciation Of Polyploid Pteridophytes Resulting From Silencing Of Duplicate-Gene Expression by Charles R.E. Werth and Michael D. Windham, American Naturalist, 137(4): 515-526 (April 1991) - DEVELOPMENT OF A MODEL TO MATCH OBSERVED SPECIATION IN NATURE

A Molecular Reexamination Of Diploid Hybrid Speciation Of Solanum raphanifolium by David M. Spooner, Kenneth. J. Sytsma and James F. Smith, Evolution, 45(3): 757-764 - DOCUMENTATION OF AN OBSERVED SPECIATION EVENT

A Mouse Speciation Gene Encodes A Meiotic Histone H3 Methyltransferase by Ondrej mihola, Zdenek Trachtulec, Cestmir Vlcek, John C. Scimenti and Jiri Forejt, Science, 323: 350-351 (16th January 2009) - DETERMINING THE FUNCTION OF A GENE DIRECTLY IMPLICATED IN SPECIATION AND FAILURE OF INTERFERTILITY BETWEEN DIVERGING POPULATIONS

A Rapidly Evolving MYB-Related Protein Causes Species Isolation In Drosophila by Daniel A. Barbash, Dominic F. Siino, Arron M. Tarone and John Roote, Proceedings of the National Academy of Sciences of the USA, 110(9): 5302-5307 (29th April 2003) - DETERMINING THE BEHAVIOUR OF A GENE DIRECTLY IMPLICATED IN SPECIATION AND FAILURE OF INTERFERTILITY BETWEEN DIVERGING POPULATIONS

A Screen For Recessive Speciation Genes Expressed In The Gametes Of F1 Hybrid Yeast by Duncan Greig, Public Library of Science Genetics, 3(2): e21 (February 2007) - Determining the presence of speciation genes in a primitive eukaryote, and the roles of any genes thus located

Adaptive Divergence And The Evolution Of Reproductive Isolation In The Wild: An Empirical Demonstration Using Introduced Sockeye Salmon by Andrew P. Hendry, Genetics, 112-113: 515-534 (2001) - DIRECT EXPERIMENTAL TEST OF REPRODUCTIVE ISOLATION AND ITS ROLE IN SPECIATION EVENTS

Adaptive Evolution And Explosive Speciation: The Cichlid Fish Model by Thomas D. Kocher, Nature Reviews Genetics, 5: 288-298 (April 2004) - DISCUSSION OF METHODS OF EMPIRICAL DEMONSTRATION OF SPECIATION INCLUDING MOLECULAR ANALYSES

Chromosomal Rearrangements And Speciation by Loren H. Rieseberg, TRENDS In Ecology & Evolution, 16(7): 351-358 (July 2001) - determination of the input that chromosomal rearrangements may have upon speciation evnets

Chromosome Evolution, Phylogeny, And Speciation Of Rock Wallabies by G. B. Sharman, R. L. Close and G. M. Maynes, Australian Journal of Zoology, 37(2-4): 351-363 (1991) - DOCUMENTATION OF OBSERVED SPECIATION IN NATURE

Evidence For Rapid Speciation Following A Founder Event In The Laboratory by James R. Weinberg Victoria R. Starczak and Danielle Jörg, Evolution 46: 1214-1220 (15th January 1992) - EXPERIMENTAL GENERATION OF A SPECIATION EVENT IN THE LABORATORY

Evolutionary Theory And Process Of Active Speciation And Adaptive Radiation In Subterranean Mole Rats, Spalax ehrenbergi Superspecies, In Israel by E. Nevo, Evolutionary Biology, 25: 1-125 - DOCUMENTATION OF OBSERVED SPECIATION IN NATURE

Experimentally Created Incipient Species Of Drosophila by Theodosius Dobzhansky & Olga Pavlovsky, Nature 230: 289 - 292 (2nd April 1971) - EXPERIMENTAL GENERATION OF A SPECIATION EVENT IN THE LABORATORY

Founder-Flush Speciation On Drosophila pseudoobscura: A Large Scale Experiment by Agustí Galiana, Andrés Moya and Francisco J. Alaya, Evolution 47: 432-444 (1993) EXPERIMENTAL GENERATION OF A SPECIATION EVENT IN THE LABORATORY

Gene Duplication And Speciation In Drosophila: Evidence From The Odysseus Locus by Chau-Ti Ting, Shun-Chern Tsaur, Sha Sun, William E. Browne, Yung-Chia Chen, Nipam H. Patel and Chung-I Wu, Proceedings of the National Academy of Sciences of the USA, 101(33): 12232-12235 (17th August 2004) - EMPIRICAL ANALYSIS OF THE ROLE OF A DEFINED SPECIATION GENE AND DUPLICATION THEREOF IN SPECIATION EVENTS

Gene Transfer, Speciation, And The Evolution Of Bacterial Genomes by Jeffrey G. Lawrence, Current Opinion in Microbiology, 2(5): 519-523 (October 1999) - determining the role of horizontal gene transfer in the development of new bacterial serotypes

Genes And Speciation by Chung-I Wu, Journal of Evolutionary Biology, 14: 889-891 (2001) - development of a rigorous theory of reproductive isolation taking into account incomplete interfertility failure events

Hybrid Lethal Systems In The Drosophila melanogaster Species Complex. II. The Zygotic Hybrid Rescue (Zhr) Gene Of Drosophila melanogaster by Kyoichi Sawamura, Masa-Toshi Yamamoto and Takao K. Watanabe, Genetics, 133: 307-313 (February 1993) - EMPIRICAL DETERMINATION OF THE ROLE OF A NAMED SPECIATION GENE IN SPECIFIC LIVING ORGANISMS

Hybridisation And Adaptive Radiation by Ole Seehausen, TRENDS In Ecology & Evolution, 19(4): 198-207 (April 2004) - development of a rigorous theory underpinning hybrid speciation and SPECIFICATION OF EMPIRICAL TESTS OF THAT THEORY

Incipient Speciation By Sexual Isolation in Drosophila: Concurrent Evolution At Multiple Loci by Chau-Ti Ting, Aya Takahashi and Chung-I Wu, Proceedings of the National Academy of Sciences of the USA, 98(12): 6709-6713 (5th June 2001) - EMPIRICAL DEMONSTRATION OF THE EXISTENCE OF GENES GOVERNING MALE MATING SUCCESS AND FEMALE MATING PREFERENCE LEADING TO SEXUAL SELECTION AND SPECIATION

Laboratory Experiments On Speciation: What Have We Learned In 40 Years? by William R. Rice and Ellen E. Hostert, Evolution, 47(6):1637-1653 (December 1993) - review of speciation literature and determination of the validity of reproductive isolation as a speciation mechanism

Models Of Evolution Of Rperoductive Isolation by Masatoshi Nei, Takeo Maruyama and Chung-I Wu, Genetics, 103: 557-559 (March 1983) - DIRECT EMPIRICAL TEST OF MODELS OF REPRODUCTIVE ISOLATION, AND ESTABLISHMENT OF CORRELATION WITH REAL WORLD DATA

Phylogenetics And Speciation by Timothy G. Barraclough and Sean Nee, TRENDS in Ecology & Evolution, 16(7): 391-399 (July 2001) - Determination of rigorous methods for using phylogenetic analyses to establish speciation events

Pollen-Mediated Introgression And Hybrid Speciation In Louisiana Irises by Michael L. Arnold, Cindy M. Buckner and Jonathan J. Robinson, Proceedings of the National Academy of Sciences of the USA, 88(4): 1398-1402 (February 1991) - OBSERVATION OF A SPECIATION EVENT IN NATURE

Premating Isolation Is Determined by Larval Rearing Substrates in Cactophilic Drosophila mojavensis. IV. Correlated Responses In Behavioral Isolation To Artificial Selection On A Life-History Trait by William J. Etges, The American Naturalist, 152(1): 129-144 (July 1998) - DIRECT EMPIRICAL TEST OF BEHAVIOURAL ISOLATION AS A MECHANISM DRIVING SPECIATION

Rapid Evolution Of Postzygotic Reproductive Isolation In Stalk-Eyed Flies by Sarah J. Christianson, John G. Swallow and Gerald S. Wilkinson, Evolution, 59(4): 849-857 (12th January 2005) - DIRECT EMPIRICAL TEST AND MOLECULAR ANALYSIS OF SEXUAL SELECTION AND HYBRID STERILITY AS MECHANISMS DRIVING SPECIATION

Role Of Gene Interactions In Hybrid Speciation: Evidence From Ancient And Experimental Hybrids by Loren H. Rieseberg, Barry Sinervo, C. Randall Linder, Mark C. Ungerer and Dulce M. Arias, Science, 272: 741-745 (3rd May 1996) - DIRECT EXPERIMENTAL TESTS OF HYPOTHESES REGARDING HYBRID SPECIATION

Searching For Speciation Genes by Roger Butlin and Michael G. Ritchie, Nature, 412: 31-33 (5th July 2001) - DIRECT EMPIRICAL SEARCH FOR GENES IMPLICATED IN SPECIATION EVENTS

Selfish Operons And Speciation By Gene Transfer by Jeffrey G. Lawrence, Trends in Microbiology, 5(9): 355-359 (September 1997) - EMPIRICAL DETERMINATION OF MECHANISMS FOR DEVELOPMENT OF NEW BACTERIAL SEROTYPES

Sex-Related Genes, Directional Sexual Selection, And Speciation by Alberto Civetta and Rama S. Singh, Molecular & Biological Evolution, 15(7): 901-909 (1998) - EMPIRICAL DETERMINATION OF THE SHAPING OF GENES IMPLICATED IN SPECIATION VIA SEXUAL SELECTION

Sexual Selection, Reproductive Isolation And The Genic View Of Speciation by J. J. M. Van Alphen and Ole Seehausen, Journal of Evolutionary Biology, 14: 874-875 (2001) - application of known speciation mechanisms to the Lake Victoria superflock of Cichlid fishes

Speciation Along Environmental Gradients by Michael Doebeli and Ulf Dieckmann, Nature, 421: 259-264 (16th January 2003) - determination of the effects of environmental pressures upon the outcome of speciation events

Speciation And The Evolution Of Gamete Recognition Genes: Pattern And Process by S. R. Palumbi, Heredity, 102: 66-76 (2009) - determination of the role of gamete recognition genes in speciation events, and their rapid evolution in segregated populations

Speciation By Hybridisation In Heliconius Butterflies by Jesús Mavárez, Camilo A. Salazar, Eldredge Bermingham, Christian Salcedo, Chris D. Jiggins and Mauricio Linares, Nature, 441: 868-871 (15th June 2006) - DETERMINATION OF A SPECIATION EVENT IN NATURE, FOLLOWED BY LABOARTORY REPRODUCTION OF THAT SPECIATION EVENT, AND CONFIRMATION THAT THE LABORATORY INDIVIDUALS ARE INTERFERTILE WITH THE WILD TYPE INDIVIDUALS (already expounded in detail above)

Speciation By Hybridization In Phasmids And Other Insects By Luciano Bullini and Guiseppe Nascetti, Canadian Journal of Zoology 68(8): 1747-1760 (1990) - OBSERVATION OF A SPECIATION EVENT IN NATURE

Speciation By Postzygotic Isolation: Forces, Genes And Molecules by H. Allen Orr and Daven C. Presgraves, Bioessays, 22(12): 1085-1094 (2000) - EMPIRICAL DETERMINATION OF THE EXISTENCE OF SPECIATION GENES AND THEIR ROLE IN INTERFERTILITY FAILURE BETWEEN SEGREGATED POPULATIONS

Speciation Genes by H. Allen Orr, John P. Masly and Daven C. Presgraves, Current Opinion in Genetics & Development, 14: 675-679 (2004) - DETERMINATION OF THE EXISTENCE OF SPECIATION GENES AND THEIR SUSCEPTIBILITY TO DARWINIAN SELECTION

Speciation, Hybrid Zones And Phylogeography - Or Seeing Genes In Space And Time by Godfrey M. Hewitt, Molecular Ecology, 10: 537-549 (2001) - review of origins of speciation theory, current developments, and application to past and present speciation events

Speciation By Habitat Specialisation: The Evolution Of Reproductive Isolation As A Correlated Character by William R. Rice, Evolutionary Ecology, 1: 301-314 (1987) - LINKING OF SPECIATION EVENTS TO NICHE MOBILITY AND ADAPTATION FOR NEW NICHES

The Evolution Of Asymmetry In Sexual Isolation: A Model And Test Case by Stevan J. Arnold, Paul A. Verrell and Stephen G. Tilley, Evolution, 50(3): 1024-1033 (June 1996) - DEVELOPMENT OF AN EXTENDED MODEL OF SEXUAL SELECTION FOLLOWED BY EMPIRICAL TEST OF THAT MODEL AND DETERMINATION OF CORRELATION WITH A REAL WORLD POPULATION DIVERGENCE EVENT

The Evolution Of Reproductive Isolation Through Sexual Conflict by Oliver Y. Martin and David J. Hosken, Nature,423: 979-982 (26th June 2003) - DIRECT EXPERIMENTAL TEST OF SEXUAL CONFLICT AS A DRIVER OF SPECIATION

The Evolutionary Genetics Of Speciation by Jerry A. Coyne and H. Allen Orr, Philosophical Transactions of the Royal Society of London Part B, 353: 287-305 (1998) review of recent advances in speciation theory and empirical results

The Genetic Basis Of Reproductive Isolation: Insights From Drosophila by H. Allen Orr, Proceedings of the National Academy of Sciences of the USA, 102 supplement 1: 6522-6526 (3rd May 2005) - review of work on speciation genes and the empirical determination of their roles

The Genic View Of The Process Of Speciation by Chung-I Wu, Journal of Evolutionary Biology, 14: 851-865 (2001) - review of theory of speciation including renewed insights into Darwin's own early view of the topic, and how this correlates to a hitherto unforeseen extent with modern genetic results

The Gibbons Speciation Mechanism by S. Ramadevon and M. A. B. Deaken, Journal of Theoretical Biology, 145(4): 447-456 (1991) - DEVELOPMENT OF A MODEL ACCOUNTING FOR OBSERVED INSTANCES OF SPECIATION

The Phylogeny Of Closely Related Species As Revealed By The Genealogy Of A Speciation Gene, Odysseus by Chau-Ti Ting, Shun-Chern Tsaur and Chung-I Wu, Proceedings of the National Academy of Sciences of the USA, 97(10): 5313-5316 (9th May 2000) - EXPERIMENTAL VERIFICATION OF A PREDICTION ABOUT SPECIATION MECHANISMS AT THE MOLECULAR LEVEL

The Population Genetics Of Speciation: The Evolution Of Hybrid Incompatibilities by H. Allen Orr, Genetics, 139: 1805-1813 (April 1995) - development of a gene-based model for speciation and the implications of the results obtained from that model for speciation research

The Theory Of Speciation Via The Founder Principle by Alan R. Templeton, Genetics, 94:1011-1038 (April 1980) - development of a model for founder speciation, and DIRECT EXPERIMENTAL TEST of that model by applying it to a real world organism

What Does Drosophila Genetics Tell Us About Speciation? by James Mallet, TRENDS in Ecology & Evolution, 21(7): 386-393 (July 2006) - Comparison of Drosophila data with data from other organisms to produce a more complete picture of speciation mechanics

I think this is pretty much Game Over for your assertion. But, there's more. I'm also aware of a paper describing an experiment, simple to conduct (it can be conducted in a high school laboratory), which will, when run to completion, generate a speciation event in the laboratory. Yes, an experiment that everyone here can conduct in their kitchens, and in doing so, generate their own speciation events if run to completion. The paper in question is this one:

Reproductive Isolation As A Consequence Of Adaptive Divergence In Drosophila pseudoobscura by Diane M. B. Dodd, Evolution, 43(6): 1308-1311 (September 1989) [Full paper downloadable from here]

According to the biological species concept, speciation is basically a problem of reproductive isolation. Of the many ways to classify isolating mechanisms, the two main divisions are premating isolation, in which mating is prevented from occurring, and postmating isolation, in which mating takes place but viable, fertile offspring are not produced. There is much debate over which type of mechanism, premating or postmating, is most likely to develop first and how the isolation comes about (e.g., see Dobzhansky, 1970; Mayr, 1963; and Muller, 1949).

In an attempt to gain insight into the process of the development of reproductive isolation, eight populations of Drosophila pseudoobscura were studied. These were first used by Powell and Andjelkovič (1983) in a study of the alpha-amylase (Amy) locus. Four were reared on a starch-based medium, and four were reared on a maltose-based medium. These two media are both quite stressful; it initially took several months for the populations to become fully established and healthy. Considering the pressure placed on the populations by the media, one would expect to see some kind of adaptive divergence between the starch-reared and maltose-reared flies.

Several changes were in fact observed in the eight populations. Powell and Andjelkovič noted an increase in the "fast" allele of Amy in the starch populations as well as an increase in one of the patterns of amylase activity in the midgut. However, no corresponding changes were seen in the maltose populations. Elsewhere (Dodd, 1984), I have presented evidence that the populations have become differentially adapted to the two media. In this study, it is shown that the populations have also developed behavioral isolation as a pleiotropic by-product of this adaptive divergence.

Basically, Dodd's experiment consisted of maintaining populations of flies, subjecting them to different dietary régimes in a manner that would result in adaptations to those régimes appearing, then demonstrating that assortative mating took place amongst the flies - in other words, members of each population exhibited a strong preference for members of their own population as mate choices.

Assortative mating is regarded as a major sign of incipient speciation, because it eliminates gene flow between the populations, thus ensuring that those populations will diverge. Eventually, said divergence will result in a fertility gap arising between the two populations. If we have two such populations, A and B, then individuals from population A can be trial mated to individuals from population B, to determine if interfertility failure has taken place. If it has, then you have a bona fide speciation event. Prior to such tests indicating interfertility failure, what you have, from a rigorous standpoint, is an incipient speciation event - the potential is there, but it hasn't actually been put to the test fully. Dodd only claimed in her paper that assortative mating was observed, but of course, assortative mating is a significant indicator that speciation is taking place, because of its effects upon gene flow. Continue the experiment for sufficient time, and interfertility failure between the divergent populations will emerge (as indeed Dobzhansky demonstrated in separate, earlier experiments with other fruit flies), at which point, we have a bona fide speciation event.

Let's delve into the paper in more detail, shall we?

Materials And Methods

All eight D. pseudoobscura populations were derived from a single population collected at Bryce Canyon, Utah (see Powell and Andjelkovič [1983] for details on the media and the generation of the populations). The four starch-reared populations were designated Ist- IVst; the maltose-reared populations were designated Ima-IVma. The flies were maintained in population cages at 25°C. The present investigation was begun approximately one year after the populations were started.

Starch-adapted populations were tested against maltose-adapted populations in every possible combination to determine whether adaptation to the two new regimes could have induced the development of ethological isolation. Multiple-choice tests were performed using mating chambers modeled on those described by Elens and Wattiaux (1964). All flies used in the mating-preference tests were reared for one generation on standard cornmeal-molasses-agar medium. Virgin males and females were anesthetized with CO2, isolated from the opposite sex, and aged on standard medium for 3-6 days. Twelve females from each of the populations to be tested were placed in the chamber. Twelve males from the two populations were then introduced as nearly simultaneously as possible. The flies were not anesthetized for this procedure. The tests were performed at room temperature (no higher than 25°C), under bright (but not direct) lighting. The chambers were observed for 60-90 minutes.

Individuals of one population had the tips of their right wings clipped to allow identification. At least two replicates of each test were performed, with the wing clipping alternated between populations. Wing clipping has not been found to interfere with mating success in Drosophila (Ehrman, 1966; Ehrman and Petit, 1968; Powell, 1978; Robertson, 1982; Knoppien, 1984; van den Berg et al., 1984; Dodd and Powell, 1985; Spiess, 1986), and once again in the present tests, wing clipping had no effect on mating propensity in either sex. Of the 1,558 matings scored, 778 were with nonclipped males, and 780 were with clipped males; 793 non-clipped females mated, while 765 clipped females mated. These differences are not statistically significant.

An isolation index (I) was calculated for each mating test. The index used follows Stalker (1942), Bateman (1949), and Merrell (1950), with the standard error derived following Malogolowkin-Cohen et al. (1965):

I = (homogamic matings - heterogamic matings) ÷ total matings(N)

Standard Error (SE) of I = [(1-I^2)/N]^½

I ranges from -1 to 1; a value of zero indicates random mating; I > 0 indicates positive assortative mating; and I < 0 indicates negative assortative mating. Contingency chi-square tests were also performed to check for deviations from random mating.

Basically, the procedure consisted of the following:

[1] Set up several populations of Drosophila pseudoobscura, divided into two groups. One group of populations is raised on a starch-rich medium (these populations are designated in her paper with the postfix "st"), and the other group is raised on a maltose-rich medium (these populations are designated with the postfix "ma").

[2] Keep these populations separate from each other for a number of generations. In Dodd's experiment, approximately 1 year elapsed before the assortative mating tests took place. For this species, 1 year equates to 8 new generations, which might seem to be a surprisingly small number of generations for any such effect to become noticeable: more usually, one would expect something like 30 or 40 generations to be required. One of the interesting features of Dodd's research, which has since been replicated with essentially the same results, is that the experimental results were obtained after just 8 generations of separation.

Oh look, an experiment in speciation that can be performed by a reasonably astute high school student in his kitchen or greenhouse, one whose results have been demonstrated repeatedly to work.

Meanwhile, there's also two species of tree frogs in the USA to consider, namely Hyla chrysocelis and Hyla versicolor. Now these two species are interesting, because, wait for it, the Hyla versicolor genome is virtually an exact copy of the Hyla chrysocelis genome, but with one important difference - the Hyla versicolor genome is duplicated wholesale. So while Hyla chrysocelis is an entirely typical diploid vertebrate (chromosomes in pairs), Hyla versicolor has two complete copies of the Hyla chrysocelis genome, with its chromosomes arranged in groups of four (tetraploid). As a corollary of this wholesale genome duplication that took place in the ancestors of Hyla versicolor, individuals of that species can no longer mate successfully with individuals of Hyla chrysocelis, despite the genetic evidence pointing conclusively to an ancestral population of Hyla chrysocelis being the ancestors of Hyla versicolor. In short, a speciation event of a particularly unusual nature took place - speciation via polyploidy. Now this mechanism has been observed occurring with some frequency in plants (Primula kewensis being perhaps the canonical example in the scientific literature to date), but observing this in vertebrates is very unusual indeed.

Again, Game Over for your assertion.

The fossil record, with few obscure exception, shows fully developed species rather than all the supposed intermediary species.

What ignorant drivel.

Oh wait, even before we consider the fact that many of these fossils constitute developmental series over time (see, for example, the tetrapod sequence from Eusthenopteron to Ichthyostega), there's another elementary concept to consider here, that destroys wholesale the "fully developed species" creationist bullshit you're peddling here. that elementary concept centres upon one readily demonstrable fact, namely, you are not identical to either of your parents, and for that matter, none of your offspring will be identical to you. In short, every population of living organisms is a dynamic entity, with the collective genomic status of that population changing with every new generation, even before mutations are factored in. Meiosis - the process by which sperm and egg cells are formed - guarantees this. As a corollary, you are a transitional form between your parents and your offspring. The same is true for every sexually reproducing eukaryote organism on the planet.

The moment mutations are introduced into the mix, matters become even more interesting, because the moment these occur, the potential for those mutations to spread to future generations and proliferate becomes open. The moment this happens (and, yes, documented instances of this happening in humans as well as other organisms exist in the literature), you have the genetic basis upon which morphological change and speciation can take place. Even in the absence of a genetic audit trail, the emergence of a systematic pattern or morphological changes (see those tetrapods again) constitutes evidence that the organisms in question were members of a clade.

Oh, and if you don't think morphological change can occur, I've known this to be a fact, courtesy of my being a tropical fishkeeper for over 35 years. Back in the 1970s, a new mutation appeared in aquarium bred populations of Betta splendens, the Siamese Fighting Fish, known as the Double Tail mutation, which results in the fish inheriting this mutation having two tail fins instead of one. Furthermore, subsequent scientific research has shown this mutation to be centred upon a single gene, exhibiting single-factor Mendelian recessive inheritance of the exact same sort that is seen in, for example, Factor VIII Haemophilia in humans. Furthermore, in the aquarium environment, the Double Tail mutation makes males more attractive as mates to females, because the finnage is expanded, and female Betta splendens prefer males with the largest fins. Therefore, if females Betta splendens are given a choice of mates, they routinely, in appropriate experiments, prefer the Double Tail males to the single tail males, which means that in that scenario, the trait is positively selectable.

I think that covers all the bases here.

"there is zero proof that life can ever start from Non life."

Straw man fallacy, as I never made any such claim, I never even mentioned abiogenesis as this has nothing to do with evolution, which explains and evidences the origin of species, not life.

You mean other then the overwhelming amount of objective evidence for the fact all living things evolved, and the indisputable fact many of those species consist of two sexes? Dear oh dear that was dumb.

"There is no proof that macroevolutiom is possible."

Macro and micro evolution are the same thing on different timescales, this is a very tired and moronic creationist canard. And again the evidence for species evolution establishes it as a scientific fact beyond any reasonable doubt.

The fossil record only show intermediary species, as all species are intermediary, again this is one of the dumbest canards creatards espouse.

"And who is to say God is complex? And just because something is asinine doesn’t mean it’s not true. Also define pixie."

Theists say it, both directly, and of course it must be inferred from their unevidenced claim the deity they believe in created everything, that this deity is more complex than it's creation. The argument you use is as valid for pixies as it is for deities, and you can define pixies in the same way as deities are defined, if theists can make things up and claim it represents sound argument then it must be valid for anything, otherwise it's selection bias as I said.

You've also ignored several rebuttals to your claims:

1. Complexity does not donate design,We know when something is designed only when there is sufficient objective evidence for design, and in every instance where this is the case we we also know those things evidenced as designed do not occur in nature.
2. How many universes did you use in your test group to establish this one is fine tuned? How do you even know any other type of universe is possible? This is a very tired religious canard. However even were true this demonstrates no objective for a designer, or a cause, and certainly none for any deity.
3. Utter gobbledegook, and please do link the breaking news that any branch of science demonstrates any evidence for any deity, as the entire scientific world seems to have missed this.
4. Irreducible complexity is creationist pseudoscience, again the entire scientific world knows this. All living things evolved, and this is an objective fact established beyond any reasonable doubt.
5. Again you are misrepresenting science as supporting your superstitious belief in a deity, just turn on any news channel to see this is a risible nonsense.
6. Nothing in science evidences a deity, or anything supernatural, you're simply lying, and it is as tedious as it is dishonest.
7. If pixies were a programmer it would easier for them to hack the programme and perform miracles, are you saying this is evidence for pixies? If not then your risible claim to be open minded is exposed as a lie, since you are biased in favour of your belief in a deity without any objective evidence to support it.
8. The creation myth in the bible is demonstrably false, making wild assertions based on subjective conjecture evidences nothing.

Did you think I wouldn't notice your evasion?