It is certainly fair to question why the Biblical kind is a better concept than any given species concept. After all, the species idea has been around for centuries and has been functional for the purposes of science, at least so we have been told. That being the case, why should we replace it with this new, Biblical kind model that has never been used for science? That is a fair question. It raises a very interesting point. Are species even real?
The reality of species is something that biologists continue to argue over. “Although most biologists agree that species are real, we lack rigorous studies needed to convince skeptics that nature is discontinuous.” By discontinuous these authors mean able to be separated into easily identifiable species.
Scientists have struggled for decades to determine whether species are real or not. However, what is it that makes a species real? What characteristics are there which, when combined together, make a real species? Let us examine the biological species concept, or simply biospecies, which for the purposes of this book will be considered the species concept, and see if we can define what makes a species real.
The Biospecies and Species Reality
How would we recognize a real species? This is a very important question to ask. There has been little in the scientific literature attempting to answer this question, and for good reason as it is a perplexing question. Usually, on the rare occasions that the reality of species is discussed, it refers to the species as a natural entity. This means species is a concept built into the natural world, like the laws of thermodynamics. Thus, species is a real concept only if there is natural evidence for its existence.
The biological species concept, the most popular concept and the one we are using for the purposes of this work, postulates that reproduction is the key to identifying a species, at least in organisms that sexually reproduce. Asexual organisms completely fall outside the biospecies and really any discussion of species. Coyne and Orr point out that most biologists agree that asexual organisms have a completely different definition of species applied to them than is applied to any other organism.
The biospecies is predicated on populations of organisms which are able to interbreed with one another, but are either unable to interact with, or unable to mate with other, similar populations. This says nothing about their ability to mate if kept together in captivity, or the potential to mate together in the wild if a geographical barrier separating them were to be removed. In a paper arguing for greater conservational efforts of even animal subspecies, Mayr and coauthor Stephen J. O’Brien indirectly proved this point. They pointed out that the Florida panther, a subspecies of Felis concolor coryi, had at one point fallen to such low population levels that government officials had introduced captive bred panthers of a different subspecies into the population. The two populations had freely interbred. In the same paper, they cited the Gray wolf (Canis lupus) population, which mitochondrial DNA studies demonstrated was infused with genes from coyotes (Canis latrans). These two examples prove that species and subspecies will freely interbreed with one another in the wild if given the opportunity.
These are certainly not the only examples that could be cited. Hybridization is common among animals, even in the wild, despite Mayr’s insistence that they are a rare occurrence. While some hybrids are bland and uninteresting because they have been known since antiquity, such as the mule (horse and donkey) others are more exciting because they are rare and unique in appearance. The wholpin (false killer whale (porpoise) and bottlenose dolphin) and liger (lion and tiger) are two of the more well-known exotic hybrids. While many of these hybrids will only be produced in captivity, the fact they exist plays into the reality of species.
Given the abundance of hybrids, even if most of them are either sterile or close to sterile, can we regard species as real? In the biospecies concept, a species is a true species if it is reproductively isolated. But if a species can hybridize, is it reproductively isolated? Once again, this depends on the meaning of terms.
In the strictest sense, anything capable of hybridization is not reproductively isolated. However, this is not what the biospecies proposes. Instead, reproductive isolation consists of a complicated set of traits including hybrid sterility, incompatible mating, and incompatible mating structures. Since most hybrids are sterile in the present, this would be taken as an indicator of reproductive isolation. However, hybrid sterility is the last line of defense as it were preventing two species from merging into one. Hybrids that are fertile, such as those produced by members of genus Xiphophorus (freshwater livebearing fish) are a significant problem to the reality of species.
This problem could be removed by simply lumping the fertile hybrid producing species into a single species, with multiple sub-species. However, this is something of a cop-out as the Xiphophorus genus is well established and has been extensively studied. Multiple species have been firmly established based on genomic studies. Thus calling this a single species seems to be a reach.
Xiphophorus is a genus which could pose significant problems to the reality of the biospecies. Other species concepts might solve this issue, but they come complete with their own issues. However, the biospecies is not concerned with the viability of hybrids produced under captive conditions as most Xiphophorus hybrids are. Captivity tends to violate reproductive isolation. However, there is strong evidence that at least one, perhaps more species of Xiphophorus originated by hybridization in the wild. While Mayr did attempt to account for this kind of hybridization in the wild, it would seem that, were species real, they should not hybridize freely.
While that is a logical conclusion, it is not what actually happens. In fact, many speciation experts, Mayr included, speak of an area of overlap or border between species called a hybrid zone. However, this describes reality, not theory. Should real species hybridize?
According to Mayr’s belief that species is the unit of evolution, yes, species should hybridize. However, these hybrids only rarely, on the evolutionary timeline, should produce viable new populations or species. As we have seen, hybrid species do exist, and form more frequently than perhaps is comfortable for the biospecies. Speciation, as they understand it, is caused more frequently by reproductive isolation arising. From a creationist perspective, it makes sense that reproductive isolation would arise as animals dispersed after the flood. However it also makes sense that hybridization would still be possible between at least some species of the same kind since they originally could breed together.
A particularly perplexing problem of speciation is the ring species idea. Coyne and Orr define as ring species as follows: “A ring species encircles a geographic barrier, such as a mountain range or plateau. Populations around the ring appear to show free exchange of genes except at a single location, where adjacent populations are reproductively isolated. Ring species are said to form when a single ancestral population gradually expands its range around the barrier. During this expansion, populations exchange genes with their neighbors, but gene flow is low between more distant populations, allowing them to differentiate more extensively. The two populations that finally meet when the ring is closed have been genetically isolated for so long that they have achieved strong reproductive isolation.”
The longwinded definition of Coyne and Orr can be broken down into a more laymanized form. A ring species is a species that encircles some obstacle and interbreed freely except at one point, where they are reproductively isolated and do not interbreed. Ring species appear on occasion in the origins debate, with even Richard Dawkins attempting to cite them as evidence for evolution in his book The Ancestors Tale. They appear often enough that at least one creation ministry has devoted a whole article on their website to addressing the concept. However, for all the bluff and bluster, there is an issue with ring species not often addressed. Just how many species are there in the ring? It could be just one species, but then why can the two terminal populations not interbreed. If it is two, then why are the intermediate populations able to inbreed? This leads to a dilemma of sorts. How many species are present? One, two, or several? Do ring species really exist or are they simply one species that has spread in a circle? This is a significant issue for taxonomists.
To be fair to Coyne and Orr, they recognize this problem. They write “But do ring species really exist? A convincing case must meet several criteria. First, there should be historical information that the ring was founded by one population rather than several genetically distinct populations, and that all individuals around the ring descend from this ancestral population. At least one of the terminal populations must represent the most recent range expansion. There must be no geographic barriers that interrupt gene flow around the ring, and such barriers must not have existed in the past. Finally, one must be able to show that gene flow is fairly excessive between adjacent populations but decreases with distance around the ring. Unfortunately, every proposed ring species fails to meet one or more of these criteria.”
The lengthy summary concludes that ring species do not even exist. Every single one proposed fails on one ground or another. While they leave the door open as to whether the two terminal populations are separate species or the same, Coyne and Orr close the door on the currently proposed ring species in no uncertain terms.
Why are the currently proposed ring species invalid? Coyne and Orr listed several characteristics that would be features of a true ring species. It would have to be provable that the ring species was originally just one population. Since we have only been observing the natural world in depth for around one hundred and fifty years and long term population studies are somewhat rare, this condition is very difficult to meet. Even if this condition is met, one of the two terminal ends must be the most recent range expansion. This makes sense if the species is working its way around a geographic barrier and is probably one of the easier conditions to meet. Further, the ring species must exhibit strong gene flow in neighboring populations that should decrease the further the populations are from one another. This seems intuitive but if two species were to merge together in a hybrid zone, while remaining discontinuous at their terminal point, this condition might not be met.
However, just meeting those two conditions is not enough. There cannot be a secondary geographic barrier interrupting the ring, nor could there have been one in the past. This is a huge problem because, unless the ring species has formed very recently. Geography changes with time, sometimes very rapidly. Thus proving that there was no geographic barrier in the past is nearly impossible. Even if the geography did not change, habitat may have. Two forest dwelling species may have been separated in the past until their separate forests grow together. This is a huge problem because often, we have little to no habitat data from more than a few decades ago.
Since there are, by the admission of evolutionists, no proposed ring species which meet these criteria, it is legitimate to question whether ring species are real or not. I suspect the answer is no, at least not as Coyne and Orr define them. Of course, this argument is underpinned by whether any species are real. As we have seen above, the reality of species is by no means established in all cases.
Even if species are real in all cases, which no one has been able to prove and I suspect no one will ever will prove based on the vast variety of forms in nature, there still remains another significant problem with species. Why do species exist? Why should there be any discontinuity between species? Why do they not grade into one another if evolution is true? This problem is very rarely even addressed in literature, yet Mayr recognized it when he proposed the biospecies concept. “The fact that the organic world is organized into species seems so fundamental that one usually forgets to ask why there are species, what their meaning is in the scheme of things.” Mayr went on to explain that reproductive isolation prevents the breakup of the gene pool, leading to an accumulation of favorable genetics.
However, Mayr is at fault here. He is trying to fit two disparate ideas into the same worldview. The evolutionary worldview, to which Mayr wholeheartedly ascribed, expects that there should be a gradual continuum of organisms gradually changing from one organism to another, with various intermediate stages along the way. In this worldview, there should be observable intermediates between each stage. In the fossil record, these are called missing links.
Of course, there are no such missing links. Mayr even acknowledges this. “Actually, the breaks in the fossil record are so frequent that it has been possible in only a few cases to piece together unbroken lineages connecting good species.” This however, runs contrary to the continuum evolution expects. Mayr does not defy the facts, that we observe discontinuity. Instead, he defies his own worldview. Other writers have been slightly more intellectually honest. “The first axiom one should certainly abandon when studying the nature of the species is the Linnaean idea that every organism belongs to some species.” Species do not seem to fit well with the evolutionary worldview.
In an attempt to explain why there are discontinuities in nature, evolutionists have proposed two reasons for why species exist. The first reason they propose ties to natural selection. The idea is that as species move into a habitat, natural selection fits the species to its habitat, thus eliminating the continuity that had previously existed. However, this is specious because natural selection only works on reproductive ability. The “winners” of the natural selection lottery are those that have the most offspring. It assumes that those that produce the most offspring will be the most fit to their environment. This is an oversimplification. Natural selection will, eventually, cause a species to become more fit to its environment but generally will not completely weed out slightly disadvantageous forms. Mayr even admitted this saying “…there is evidence that some of the genetic variation is directly maintained by natural selection.” So there should still be some level of continuity between species that would enable us to trace ancestry. Yet Mayr also admitted a lack of transitional forms. These two positions run contrary to one another.
The second major proposal is that species are consequences of sexual reproduction and reproductive isolation. Essentially this idea is that, as creatures mate, they will produce discontinuity based on their genetics. As this discontinuity becomes reproductively isolated, it becomes fixed to an extent and the continuum is lost. However, this idea has been partially refuted in some asexual organisms. One study, on bdelloid rotifers, concluded that asexual organisms could produce species. “We conclude that bdelloids display the same qualitative pattern of genetic and morphological clusters, indicative of diversification into independently evolving and distinct entities, as found in sexual clades. This refutes the idea that sex is necessary for diversification into evolutionary species.” This completely destroys this explanation for why species exist, forcing evolutionists to rely on natural selection even further for an explanation for the existence of species.
Ironically, Darwin was the first to recognize this problem, something that Mayr acknowledged. “This contradiction worried Darwin and the early Darwinians considerably. Since they considered inheritance to be blending, they had to assume that, owing to blending, one-half of the total variability would be lost in each generation. At the same time, the availability of an inexhaustible supply of genetic variation was one of the cornerstones of Darwin’s theory. These two assumptions were completely in opposition to each other. There seemed only one answer to this conundrum, a truly colossal rate of mutation.” Of course, Darwin knew nothing about the work of Gregor Mendel, or genetics, leaving him ill-equipped to explain heredity. However, he did clearly understand his own theory. He expected that, since all organisms evolved from a common ancestor, they should all grade into one another. Thus, a blending of sorts was expected. This led to him being puzzled by the obvious discontinuity on display in the world.
The escape hatch for Darwin was a colossal rate of mutations. Such a rate has never been observed and has been effectively refuted by Mendelian genetics. Thus, a gradient of sorts between species should be expected as the end result of the step-wise descent with modification that Darwin proposed.
The extent of this problem has not escaped evolutionists. In fact, this was one of the reasons Nils Eldredge and Stephen Gould formulated the saltatory theory of punctuated equilibrium to explain the missing links. “Instead of species continuously grading into one another, we actually observe discrete species (and higher categories) with comparatively little evidence of transition. Gould and Eldredge interpret this pattern as evidence of rapid evolution in small populations, wherein evidence of transition is not preserved.” Gould and Eldredge recognized there were no missing links tying species together and attempted to deploy a rescuing device to keep their favored worldview afloat. While the punctuated equilibrium hypothesis has fallen out of favor with most of the orthodox evolutionary community, the fact it gained popularity at all illustrates that distinct species with no intermediates are a problem for Darwinian evolution.
This is the difficulty then with harmonizing the knowledge of genetics available to modern science, and what evolution actually logically requires. Genetics requires separate, distinct kinds and in some cases distinct genetic species. Evolution requires gradual changes between species, with each of those changes increasing fitness for the environment the organism lives in. In this case, there should be a nearly unnoticeable difference between each species, both genetically and morphologically. It should be possible to completely trace the path of a species, particularly with the deep time postulated by evolution, complete with fossils of extinct forms. As Mayr acknowledged above, this is not possible. Species, sometimes even subspecies, exhibit vast differences in morphology, behavior, and even genetics. This is completely opposite of what evolution expects.
Speciation thus proves both a blessing and a curse to Darwinian evolution. It was a blessing in that it allowed the idea to promulgate itself in the 1800s as many scientists and layman began to recognize that species were not fixed. However, what is logically required for Darwinian evolution is not what science observed. Thus, speciation actually is evidence against Darwin’s theory. For evolution to be true, it should not be possible for someone like Mayr to write a 600 plus page tome on species, since species should be largely indistinguishable from one another.
The Created Kind
Evolutionists might counter that creationists have a similar problem. However, this is a terrible argument, because it is effectively shifting the blame, and it is completely false. Simply saying an argument is valid because another argument has problems is purely specious, no matter who makes it. The argument is also false because creationists do not need species. We are not reliant upon species as the unit of variety. To the creationist, the created kind, the baramin, is the unit of variety. Certainly, there is variation within the created kind. No creationist today disputes that. However, the process of speciation is not evolution. Speciation “…is compatible with the story of creation in the book of Genesis.” That last sentence was not written by a creationist. It comes from no less an authority on speciation than Ernst Mayr, a lifelong evolutionist. Unlike many evolutionists today, Mayr was educated enough on creationist positions to know that creationists freely accept speciation, within the limits of the baramin.
Some evolutionary criticisms of the created kind concept are valid. However, the more usual ones are not. Usually they come in the form of mockingly asking where the kind falls on the Linnaean classification scale. This particular criticism completely misses the point. The Linnaean classification system was designed by man to aid in classification, and thus is incredibly useful. However, no man-made classification system will ever perfectly match the classification system designed by God. Because God is omniscient, He could design a perfect classification, and in fact He did…the created kind.
The fact that most evolutionary criticism of the created kind is invalid, does not mean that there are not issues with our current understanding. Because science is dominated almost without exception by atheistic evolutionary individuals, understandably little work has been done studying the created kinds. This is slowly changing, with the emerging field of baraminology, which we will discuss in Chapter 8. However, even in creation circles, geological research has been predominant over the study of the kinds. This is regrettable, and this book is, in part, written to change that.
There are significant positives to using the Biblical kind alongside or perhaps in place of Linnaean classification. The most obvious positive is that the created kind is universal. Unlike species, which, as discussed in the previous chapter, cannot be made universal, God laid down kind as a universal concept in Genesis 1. He uses the same word to refer to the reproductive groupings of plants and animals alike. This is a massive benefit because it greatly simplifies classification. Once we know what a kind is, the same term can be applied with equal honesty and objectivity to everything from microbes to mammals.
In chapter one, we defined a Biblical kind simply as a reproductive grouping. However, that description only worked in the past. Post-fall variation and mutations caused a certain amount of speciation. Creationists recognize this. In is definitive work, Replacing Darwin, Dr. Nathaniel Jeanson points out that Darwin equated breed formation with formation of species. However, evolutionists postulate that almost all domestic breeds arose in the last 12,000 years. “By the evolutionists’ own logic, species must have arisen in 12,000 years or less.” While evolutionists love to attack creationists, Dr. Jeanson points out that, using their twelve thousand year time scale, mammal species would have to arise at a rate of a mere 2.2 a year. Even cutting that in half to match the Biblical timeline would make a rate of 4.4 species a year for mammals. That number would not be hard to obtain.
In fact, it is the evolutionists who should be troubled by the number of species. In a collection of essays on speciation, G. Ledyard Stebbins points out that based on an evolutionarily preferable rate of speciation, assuming no extinction, there would be over one billion species on planet earth in just one million years. Given that earth is believed to be billions of years old and life is supposed to be hundreds of millions of years old, this would require a colossal rate of extinction to reach today’s observable number of species. The fossil record does not bear this out.
However, this speciation has complicated the definition of the Biblical kind somewhat. Because of the speciation, some members of the same kind cannot interbreed any longer, while others interbreed freely. This causes a problem for the baraminologists attempting to segregate one baramin from another. How can one baramin be told from another? This is a peculiar problem. In some cases, reproduction between members of the created kinds is still possible and even a regular occurrence. However, in others, it rarely or never occurs. We will address this problem more fully in chapter 8. For the moment, we will consider hybridization as the primary characteristic defining created kinds and briefly examine some studies that have been done in the baraminology field.
As of this writing, the most recent baraminology study available that I’m aware of comes from Jean O’Micks in the Answers Research Journal. O’Micks has contributed periodically to creationist baraminology literature, the most recent contribution being a baraminology of cephalopods. Using baraminological methods that will be detailed in chapter 8, O`Micks concluded that, if mtDNA was used as the defining characteristic, then cephalopods fall into potentially four separate created kinds, one containing octopi and cuttlefish, two containing squids, and potentially one containing the nautiluses. However, using morphology as the defining characteristic results in two baramin, one containing squids and cuttlefish, the other containing the octopi. O’Micks emphasized throughout the paper that this was a preliminary study and more work is needed on cephalopods. I would concur, particularly since, as best I can tell, no hybridization data for any cephalopods exists in the scientific literature.
This study by O’Micks illustrates the problems creationist has when attempting to delineate the created kinds. Often creationists lack access to facilities and tools needed to gather their own data. Instead, they are forced to rely heavily on secularly obtained data sets, as O’Micks does, and interpret the results. Hybridization data is also often sorely lacking. Sometimes this is because some of the species involved are endangered and thus scientists are likely to be strongly opposed to hybridizing them. Others may require very special conditions to mate that may be impossible in captivity. This, of course, is not the only problem.
Another significant issue when performing baraminology is weighing genetic data against morphological and hybridization data. Morphological data is the easiest to obtain, but probably the least useful for several reasons. Since it is based purely on external traits, it is heavily ecologically dependent. In other words, creatures in the same habitat will likely have similar traits. This tends to obscure the baramin. Sometimes observation of body plans can give baraminologists a general idea of a baramin, but other times this is complicated.
While morphological data is likely the least valuable of the data available, hybridization and genetic data show more promise. Some creationists have argued exclusively for a genetic definition of the kind. This runs counter to Marsh’s original proposition of the created kind. “I am of the opinion that the union of two gamete nuclei, regardless of the dissimilarity of the individuals from which they come, and regardless of the fact that development may cease in the early stages, is evidence that the parents are members of the same Genesis kind.” It seems likely that a combination of the two is the best solution. However, this raises the problem of lack of genetic data for many organisms. This problem is likely to lessen in the future as a project has been announced to sequence the genome of every organism on earth. As the data from such projects increase, baraminology studies are likely to become less tentative.
Despite the tentative nature of most baraminology studies, there is still great value to them. It allows creation scientists to understand the created world better and better explain how organisms interact with one another. It also permits creationists to answer the skeptic’s complete misunderstanding that evolutionists have about the original created kinds.
Typical evolutionists mockery of the created kinds is in reference to the number of animals on the Ark. This is where baraminology studies become crucial. While the Answers Research Journal has featured numerous articles attempting to estimate the various ark kinds, these are initial estimates only. In fact, Ken Ham admits as much, frequently mentioning in his talks that Answers in Genesis believes they have overestimated how many kinds were on the ark. To narrow it down, we need further baraminology studies, particularly on creatures that may have been on the ark. In chapter 8, we will discuss baraminology studies in greater detail, as well as documenting some original baraminology work.
The Kind or The Species?
As we have seen in this chapter, the species concept is riddled with problems and issues. Scientists cannot even demonstrate that species are a real concept. In discussions with several evolutionists, more than one has told me that species are either not real or are completely arbitrary. One evolutionist, who was well versed in phylogenetics and cladistics, told me that the true unit of variety is the individual and that species are only classified as such for convenience. Not all of these were professional scientists, so their word should be taken with a grain of salt. However, the same theme appears in the scientific literature. One study asked this very question and came to the conclusion that species are real on a limited basis. But this fails the test because a truly real species is a natural concept, not one that only occurs on a limited basis. Nowhere can a natural definition of species be found.
This is not to say that species is not a useful term, it is. Linnaean classification, which we will discuss in chapter seven, is a manmade system, and is therefore fallible. That does not make it useless. Having the ability to organize organisms into groups is very useful to assist in studying the natural world. However, it is an arbitrary definition. This is evidenced in the sheer number of species definitions that exist in the literature. Moreover, it is not universal. Attempting to apply the same species definition to different types of organisms generally fails yet attempting to change the definition of species to match various types of organisms generates confusion. Perhaps species ought to be reserved for members of the sexually reproducing taxa only.
Creationists have been aware of this problem for decades. One creationist, presenting to the International Conference on Creationism, said in discussing the species problem “…a final solution probably does not exist.” The author then goes on to discuss some of the issues involved with the species concepts, particularly the biospecies, before discussing the baramin. Evolutionists also recognize the problem, as mentioned by Coyne and Orr above.
Even granting that species is a real concept, which is strongly in doubt, there is nothing to explain the lack of continuity between species. Not all species are discontinuous of course, but there are massive gaps in the species record which should not exist if they all shared a common ancestor. Mayr admitted this gap exists, and later Stephen Jay Gould would admit to the same. While evolutionists will quickly deny the absence of missing links, they readily accept discontinuity between species, which defies their theory. The cognitive dissonance involved is sometimes difficult to accept.
The Biblical kind is a much better concept. It is a universal concept, able to be applied to fossils, microbes, and the sexually reproducing taxa. Because it is universal, there is little confusion in using term “kind”. A fossil taxon can just as easily be called a kind as a living one, using the same definition of the word.
Further a kind is a real, natural vehicle, rather than an arbitrary one. Kinds can be delineated somewhat instinctively. Marsh recognized this in his original work on the created kinds. “In the living world, baramins are usually easy to distinguish.” Perhaps the easiest illustration of this comes from the horse kind. If a child is presented with the image of a zebra and a horse, most likely they will identify them as being very similar. Even adults can often do this without difficulty. This would also apply to dogs, cats, elephants, and so on. This gives the baramin a native simplicity, making it easy to use for even the scientific layman.
Thus, we can observe, based on the arguments presented in
this chapter, that the Biblical kind is a much better concept than the Linnaean
species. This is not to say the Linnaean
species is useless or should be abandoned. It is a very valuable, useful tool
for research. However, even with the value it provides to research, the species
is, at its heart, arbitrary because it is defined by man. Because the kind is
defined by God, it has a hard, immutable definition that is not arbitrary or
subject to reinterpretation, making it a far better concept than the Linnaean
 Coyne and Orr, 2004.
 Stephen J. O’Brien and Ernst Mayr. “Bureaucratic Mischief: Recognizing Endangered Species and Subspecies.” Science Volume 251, No. 4998 (1991) Pages 1187-1188. https://pdfs.semanticscholar.org/d9c6/f4e3ddbc98ea0145484e9add7c045a260aee.pdf
 Mayr, 1965.
 Yingjia Shen, Domitille Chalopin, Tzintzuni Garcia, Mikki Boswell, William Boswell, Sergey A. Shiryev, Richa Agarwala, Jean-Nicholas Volff, John H. Postlethwait, Manfed Schartl, Patrick Minx, Wesley C. Warren, and Ronald B. Walter. “X. couchianus and X. hellerii genome models provide genomic variation insight among Xiphophorus species.” BMC Genomics Volume 17, No. 37. (2016) https://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-015-2361-z
 Don C. Morizot and Michael J. Siciliano “Protein Polymorphisms, Segregation in Genetic Crosses and Genetic Distances Among Fishes of Genus Xiphophorus (Poeciilidae).” Genetics Volume 102 (1962) Pages 539-556. http://www.genetics.org/content/genetics/102/3/539.full.pdf
 Axel Meyer, Walter Salzburger, and Manfred Schartl. “Hybrid origin of a swordtail species (Teleostei: Xiphophorus clemenciae) driven by sexual selection.” Molecular Ecology Volume 15, No. 3. (2006) Pages 721-730. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-294X.2006.02810.x
 Mayr, 1965.
 Coyne and Orr, 2004.
 Carl Weiland “Birds of a Feather Don’t Breed Together.” Creation.com Accessed November 8, 2018. https://creation.com/birds-of-a-feather-don-t-breed-together
 Coyne and Orr, 2004.
 Mayr, 1965.
 Kalevi Kull. “The Biosemiotic Concept of the Species.” Biosemiotics Volume 9 (2016). Pages 61-71. DOI 10.1007/s12304-016-9259-2
 Timothy G. Barraclough and Elisabeth Herniou. “ Why do species exist? Insights from sexuals and asexuals.” Zoology Volume 106 (2003) Pages 275-282. https://www.sciencedirect.com/science/article/pii/S094420060470104X
 Mayr, 1965.
 Barraclough and Herniou, 2003.
 Diego Fontaneto, Elisabeth A. Herniou, Chiara Boschetti, Manuela Caprioli, Guilio Melone, Claudia Ricci, and Timothy G. Barraclough. “Independently Evolving Species in Asexual Bdelloid Rotifers.” PLOS B Volume 5, No. 4 (2007) https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0050087
 Mayr, 1965.
 Saltations are rapid changes from one kind of organism to another.
 Todd Charles Wood and Megan J. Murray Understanding the Pattern of Life. Nashville, TN: Broadman & Holman Publishers, 2003.
 Baramin comes from two Hebrew words, bara meaning to create or created, and miyn meaning kind. Put together, the words mean “created kind”.
 Mayr, 1965.
 Nathaniel Jeanson Replacing Darwin Green Forest, AR: Masters Books, 2017.
 Luther Val Giddings, Kenneth Y. Kaneshiro, and Wyatt W. Anderson eds. Genetics, Speciation, and the Founder Principle (New York: Oxford University Press, 1989.)
 Baraminologists are those who study the created kinds.
 Jean O’Micks “A Preliminary Cephalopod Baraminology Study based on the Analysis of Mitochondrial Genomes and Morphological Characteristics.” Answers Research Journal Volume 11, (2018). Pages 193-204. https://assets.answersingenesis.org/doc/articles/pdf-versions/arj/v11/cephalopod_baraminology_mitochondrial_genomes.pdf
 Lane P. Lester and Raymond G. Bohlin. “After His Kind: The Biological Unit of Creation.” Proceedings of the International Conference on Creationism Volume 1 (1986) http://www.creationicc.org/1986_papers/ICC86V1-12.pdf
 Marsh, 1976.
 Elizabeth Pennisi. “Biologists propose to sequence the DNA of all life on Earth.” Science February 24, 2017. Accessed November 12, 2018. https://www.sciencemag.org/news/2017/02/biologists-propose-sequence-dna-all-life-earth
 Sebastien Gourbiere and James Mallet. “Are Species Real? The Shape of the Species Boundary with Exponential Failure Reinforcement and the ‘Missing Snowball”” International Journal of Organic Evolution Volume 64, No. 1 (2010) Pages 1-24. https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1558-5646.2009.00844.x
 Siegfried Scherer “Basic Types of Life” Proceedings of the International Conference on Creationism Volume 3 (1994) http://www.creationicc.org/1994_papers/1994_Part46.pdf
 Marsh, 1976.