On the Origins of New Forms of Life
A New Theory

An alternative approach to biology



Stabilization theory provides an intellectual basis for Charlie Chaplin's dream:

A complete presentation of stabilization theory, an alternative theory of evolution, appears below (to read a brief description of how this theory differs from conventional evolutionary theory, click here). The sentiment that inspired this detailed reassessment of evolutionary thought is the journalist's motto: "If your mother says she loves you, check it out!"

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A personal endorsement:

"As a clinician and scientist with medical training it is a joy to find a theory so carefully and elegantly presented. My interest in the hybrid nature of modern man led me to Eugene McCarthy's website and lifework. What a revelation! Surprising and shocking. Such is the nature of truth sometimes. Life will never be seen in the same way after reading this work."

Dr Chris Millar
Ballarat, Victoria, Australia
Another endorsement:

"I have just started reading your book On the Origins of New Forms of Life. By training, I am a theoretical linguist, not a biologist, but I have been drawn more and more to (evolutionary) biology during the last few years, and getting very frustrated with the Neo-Darwinian framework that blinds us to interesting questions. As an academic, I hate to use superlatives, but I find your book brilliant, to say the least. I am so glad that I happened to bump into the book, three weeks before a brain-storming/retreat conference on the foundations of evolutionary theory in which I have been asked to outline an outsider's view of (frustrations with?) evolutionary theory."

K. P. Mohanan
Indian Institute of Science Education and Research
To cite this work:

McCarthy, E. M. 2008. On the Origins of New Forms of Life. macroevolution.net
Are we hybrids? da Vinci
By the same author:
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Preface >>


Documentation: The material presented here, unlike that in the ebook version, is as yet only partially documented. Installation of the documentation for the online version, which is very time-consuming, is in process. For detailed and complete documentation, access the e-book version pdf by clicking here.

An anonymous peer review received by Oxford University Press:

"Thank you for sending me a copy of Gene McCarthy’s manuscript On the Origin of New Life Forms [this was the working title of the manuscript at the time of the review] for Oxford Univ. Press. I have now read the entire book, and in fact I could hardly put it down! This is a wonderful, indeed marvelous book that you absolutely must publish ASAP. At the risk of sounding overly ebullient, this is one of the most exciting and potentially revolutionary treatments of evolutionary biology (while still being plausible) that I have encountered in recent memory. The work is scholarly, beautifully researched, remarkably comprehensive, sometimes hyperbolous, and highly provocative (but in a generally positive way). Furthermore the writing itself is exquisite. In each chapter of the book, I found myself relishing not only the thrust of [the author’s] central argument and the prospect of where it might be headed, but also on the multitudinous details, pithy phrases, and extensive quotations from both the recent and ancient literature that [he] has used with great effect to present and defend his arguments."

"The approach that McCarthy has taken is the stuff of which Kuhnian revolutions are built. He has taken many puzzling and sometimes troubling aspects of conventional neo-Darwinian evolutionary thought, and woven them together to motivate a grand novel hypothesis (stabilization theory) that interprets these problematic areas in a new light. Among the contentious subjects that McCarthy reinterprets and purports to resolve in the light of stabilization theory are the following: the concepts and definitions of species and why these have so long remained controversial; the origin and role of karyotypic changes in the evolutionary process (a topic that has been largely neglected since the 1950s); the puzzlement of why different gene trees seem so often seem to support different organismal phylogenies; general uncertainties about the mechanisms and processes underlying reproductive isolation; and the issue of how to reconcile the appearance of punctuated stasis in the fossil record with the well-known mechanisms of traditional population genetics. McCarthy argues that these and other major dilemmas under traditional speciation theory largely dissolve under the evolutionary scenario he develops, wherein hybridization often provides the initial stimulus and fodder for evolutionary change by introducing into lineages a wealth of otherwise unavailable genetic variation (especially karyotypic) from which new species then sometimes emerge as stabilized recombinant derivatives. The hypothesis is bold, at least plausible, difficult to broadly refute, and yet also ultimately testable. Such testing can involve, for example, more critical appraisals of whether (and if so, why) gene trees often lack full concordance with one another in the organismal trees they seem to support. [Is this because of homoplasy and the idiosyncrasies of lineage sorting (as is often supposed in much of the recent literature), or is it because evolution is far more reticulate than formerly imagined] Many other research lines are also suggested, directed for example toward understanding both descriptively and experimentally the actual consequences of interspecific hybridization. Indeed, this book should stimulate fresh evolutionary perspectives, worthy of further exploration, in a wide set of research arenas."

To read the remainder of this review, please click here.

In his book, In the Light of Evolution (2008), renowned evolutionary biologist John Avise says that if the views presented on this website are correct, our ideas of biology and the evolutionary process will have to be revised at a fundamental level. There, he states that:
"First, phylogeneticists would have to admit that their dream of reconstructing a branched tree of life had been merely a pipedream, and they would have to accept the new and probably far more difficult challenge of working out the precise history of reticulation events for each organismal group and how such reticulate genealogical histories have idiosyncratically distributed particular bits and pieces of DNA from disparate sources to extant taxa. Traditional concepts of species, phylogeny, ancestry, and classification, as well as the significance of reproductive isolation, would all have to be reevaluated. Biologists would have to embrace the notion that biological processes falling somewhat outside the standard neo-Darwinian paradigm for speciation (such as interspecific hybridization and the reproductive stabilization of genetic-recombinant derivatives) could play major and previously underappreciated roles in evolution. They would have to reevaluate the origins of genetic variation on which natural selection acts and how novel phenotypic adaptations and different forms of life mechanistically come into being. In short, major shifts in evolutionary thought would be required, and this would open wonderful opportunities for the eventual emergence of a grandly updated evolutionary synthesis, 21st-century style." — From In the Light of Evolution, Volume II: Biodiversity and Extinction, 2008, pp. 288–289.

Why I chose to create an alternative theory of evolution and my approach to doing so. Read on >>


This section discusses some of the serious problems biologists have had with defining species, a word at the heart of modern evolutionary thought.

  • 1.0 Introduction. A brief explanation of why the word species needs to be dealt with before any real progress can be made in evolutionary thought. Read on >>

  • 1.1 On the origin of the word species. Species was originally a word used by philosophers, for whom it had a much clearer meaning than it has for scientists today. Read on >>

  • 1.2 The natural order. An account of how scientists inherited the term species from the schoolmen of the medieval era. Read on >>

  • 1.3 Hybrids and immutability. Read how early naturalists thought of hybrid sterility as the essential factor maintaining the natural order. Read on >>

  • 1.4 Carolus Linnaeus rejects creationism. Read how Linnaeus was the first major naturalist to break with the idea of immutability and how he proposed one of the first evolutionary theories.
    Read on >>

  • 1.5 Creationism versus hybridization. How creationists responded to Linnaeus' theory Read on >>

  • 1.6 Binomial nomenclature. An explanation of what it means to be "treated as a species." Read on >>

  • 1.7. The "essence" criterion. John Locke's cogent critique of "species." Read on >>

  • 1.8 Definitions of species. A discussion of the various concepts of "species." Read on >>

  • 1.9 Reproductive isolation: A vague criterion. Why reproductive isolation can never serve as a satisfactory basis for defining species. Read on >>

  • 1.10 Species: Resolving the problem. A simple way to resolve the species question. Read on >>


A discussion of hybridization, particularly those aspects of hybridization relevant to stabilization theory.

  • 2.0 Introduction. Hybridization, and basic phenomena related to hybridization, described and explained. Read on >>

  • 2.1 More about hybridization. About gametes, reciprocal crosses, and the effect of hybridization on gametes. Read on >>

  • 2.2 Variation in hybrids. A description of the kinds of variation typically seen in hybrids. Read on >>

  • 2.3 Heterosis and synergistic effects. Traits produced by hybridization often lie outside the parental range of variation.
    Read on >>

  • 2.4 Hybrid populations. On the characteristics of populations produced by hybridization. Read on >>

  • 2.5 Hybrid taxa. Many hybrids, and hybrid populations, have been treated as species. Read on >>

  • 2.6 Hybrid animals: Artificial selection. How breeders use hybridization to produce new kinds of animals. Read on >>

  • 2.7 Hybrid plants: Artificial selection. How breeders use hybridization to produce new kinds of plants. Read on >>

  • 2.8 Triangular numbers & Section conclusion. The simple mathematics of triangular numbers shows that the number of hybrid pairings far exceeds the number of types being paired. This fact suggests that even if a small percentage of crosses produce viable hybrids, many types of crosses will still produce viable offspring.
    Read on >>


This section (which is not divided into separate web pages) describes and defines various phenomena basic to stabilization theory. Read on >>


Under stabilization theory, new types of organisms are typically produced by stabilization processes. This section describes a variety of these processes, and gives examples of each.

  • 4.0 Introduction. Introduction to the Section 4. Read on >>

  • 4.1 Vegetative reproduction. The fact that many organisms can reproduction without sex is of fundamental importance to stabilization theory. Read on >>

  • 4.2 Alternative life cycles. The ability of many organisms to reproduce by alternative means facilitates the production of new types of organisms via stabilization processes. Read on >>

  • 4.3 Stabilization processes. The ability of many organisms to reproduce by alternative means facilitates the production of new types of organisms via stabilization processes. Read on >>

  • 4.4 Polyploid production. Another common type of stabilization process is the production of a polyploid. Read on >>

  • 4.5 Aneuploid production. Aneuploidization is an additional type of stabilization process. Read on >>

  • 4.6 Permanent translocation heterozygotes. Among plants, many new stable forms are produced by the stabilization of a new, permanent translocation heterozygote. Read on >>

  • 4.7 Production of new agamosperms. An additional way to stabilize a new type of organism is to stabilize a new agamosperm. Read on >>

  • 4.8 Agamic complexes. Complexes composed of a wide variety new forms can arise via repeated production of agamosperms which hybridize among themselves to produce additional, new types of agamosperms. Read on >>

  • 4.9 Production of vegetative forms. One type of stabilization process is the production of a new stable type via such processes as budding and fragmentation. Read on >>

  • 4.10 Production of Symbiotic Associations. In symbiosis, organisms form permanent associations. Many such associated pairs are treated as species. Read on >>

  • 4.11 Recombinational Stabilization. Under stabilization theory, one of the most important types of stabilization processes is recombinational stabilization. Read on >>

  • 4.12 Conclusion. Section conclusion and summary. Read on >>

This section attempts to evaluate the prevalence of stabilization processes. That is, are they common enough to be evolutionarily significant?

  • 5.0 Introduction. Introduction to the Section 5. Read on >>

  • 5.1 The prevalence of polyploidy. How common is the production of new forms through polyploidy? Read on >>

  • 5.2 The prevalence of vegetative reproduction. How many different types of organisms are capable of vegetative reproduction? Read on >>

  • 5.3 The prevalence of natural recombinant derivatives. How often do new types of natural recombinant derivatives arise?
    Read on >>

  • 5.4 Apomixis and triangular numbers. How apomixis and vegetative reproduction help new sexual forms get established. Read on >>

  • 5.5 The prevalence of animal hybrids. The production of new forms via stabilization processes will be more common if hybridization is more common, and animal hybrids — even in a natural setting — are more common than many people realize. Read on >>

  • 5.6 The scala naturae. A long-standing tradition has asserted that animals are "higher" and more "complex" than plants. This notion has promoted the idea that hybrids are rarer among animals than among plants. Read on >>

  • 5.7 Predicted phylogenies disagree. Predicted evolutionary relationships frequently differ when they are inferred from different data sets. This fact suggests the production of new forms via hybridization has been rampant over evolutionary time. Read on >>

  • 5.8 Known origins. Known examples in which new forms of life have been produced by stabilization processes provide proof that evolution does in fact occur. Read on >>

  • 5.9 Conclusion. Section conclusion and summary. Read on >>


This section discusses paleontological data (which is consistent with the claims of stabilization theory, but not with those of conventional theory).

  • 6.0 Introduction. Introduction to Section 6. Read on >>

  • 6.1 Cuvier. Baron Georges Cuvier (1769-1832) was the first scientist to assert that the typical fossil form does not change over geological time. Read on >>

  • 6.2 Darwin's emphasis on gradualism. Darwin believed explanations of origins are somehow more scientific when described in terms of gradual processes. This led him to make unfounded claims in his theory. Read on >>

  • 6.3 Paleontologists' objections to gradualism. Many paleontologists objected to Darwin's claims that new forms of life typically come gradually into being. Many still do. Read on >>

  • 6.4 Saltation versus gradualism. During the eighty years following the publication of the Origin, many naturalists had saltationist views.
    Read on >>

  • 6.5 Stephen Jay Gould and Niles Eldredge. How Niles and Eldredge resurrected saltation under the new name of punctuated equilibrium.
    Read on >>

  • 6.6 Peripheral isolates and speedy gradualism. Gradualists offer two explanations for the phenomenon of punctuated equilibrium. Neither is very convincing. Read on >>

  • 6.7 Conclusion. Conclusion and summary for Section 6. Read on >>

This section discusses the long search saltationists have had for an unknown force behind evolution, and suggests what that force might be.

  • 7.0 Introduction. Introduction to Section 7. Read on >>

  • hugo de vries
    7.1 Hugo de Vries. About Hugo de Vries, the last highly successful saltationist prior to Eldredge and Gould. Read on >>

  • 7.2 Darwin and saltation. Darwin's attitudes toward saltation. Read on >>

  • 7.3 From de Vries to the modern synthesis. The decline in popularity of de Vries' theory and the rise of genic evolutionary thought. Read on >>

  • 7.4 A Tradition becomes a heresy. How saltationist thought, a long tradition in biology, became a scientific heresy. Read on >>

  • 7.5 From one karyotype to another. The beginning of stabilization theory's explanation of evolution. Read on >>

  • 7.6 Types. Despite the claims of population geneticists, stable types are what is seen in the fossil record. Read on >>

  • 7.7 A caveat. Stabilization theory does not entirely dismiss the claims of population genetics, but it does downplay their significance. Read on >>

  • 7.8 Stability of form. Stabilization theory accounts for the stability of form observed in most organisms. Read on >>

  • 7.9 Enhanced effect of point mutations. Under the assumptions of stabilization theory, point mutations would be more effective in producing evolutionary change than under those of conventional theory. Read on >>

  • 7.10 A Basis for hybrid infertility. Stabilization theory provides a clear explanation of the widespread phenomenon of hybrid infertility (conventional theory fails in this respect). Read on >>

  • 7.11 The nature of natural selection. Under stabilization theory, natural selection differs in nature from what has been described under conventional theory. Read on >>

  • 7.12 Gradualists are not true uniformitarians. Gradualism is inconsistent with uniformitarian doctrine. Read on >>

  • 7.13 Position effects. Explanations of saltation in terms of position effects do not account for certain well-documented phenomena. Read on >>

  • 7.14 Hybrids in the fossil record Why one would expect hybrids to be rare in the fossil record. Read on >>

  • 7.15 Hybrids versus stable types A look at the two sides of evolution through stabilization processes and a summary for Section 7. Read on >>


This section explains how types diversify under stabilization theory.

  • 8.0 Introduction. Introduction to Section 8. Read on >>

  • 8.1 Dubious assumptions. Problems with the assumptions biologists make about homology and analogy. Read on >>

  • 8.2 Similarity chains and similarity sets. How traits spread under stabilization theory. Read on >>

  • 8.3 From simple to complex. How complexity arises under stabilization theory. Read on >>

  • 8.4 The concept of radiation. Problems with the concept of an evolutionary radiation. Read on >>


A reevaluation of the fabled K-T extinction suggests it actually was, in large degree, a fable. Was the so-called mammalian radiation primarily a matter of extensive re-identification of preexisting types?.

  • 9.0 Introduction. Introduction to Section 9. Read on >>

  • 9.1 The Mesozoic Era. Concerning the usual story told about the Mesozoic Era. Read on >>

  • 9.2 Synapsids. What were they really? Read on >>

  • 9.3 Pangolins and armadillos. Have stegosaurus and ankylosaurus, two of the most famous dinosaurs, been misclassified as reptiles? Read on >>

  • 9.4 Primates and the origin of placental mammals. The geographic distribution of primate fossils indicates placental mammals arose far earlier than is commonly supposed. Read on >>

  • 9.5 Gliriforms. Were multituberculates the precursors of rodents and lagomorphs? Read on >>

  • 9.6 Bats. Under conventional theory the origin of bats has been a mystery, but likely precursors, probably misclassified as reptiles, existed in the Mesozoic Era. Read on >>

  • 9.7 Ungulates. On the origin of hoofed mammals. Read on >>

  • 9.8 On the evolution of whales. Had whales already come into being in the Mesozoic? Read on >>

  • 9.9 Terrestrial predators On the origin of terrestrial predators. Read on >>

  • 9.10 Pinnipeds. On the probable Mesozoic precursors of seals. Read on >>

  • 9.11 Proboscideans. Elephants are probably of far more ancient origin than is generally supposed. Read on >>

  • 9.12 Marsupials & Conclusion. On the origins of marsupials and the conclusion of Section 9. Read on >>


The author's thoughts on stabilization theory and its potential significance.
Read on >>


  • Appendix A: The limits of directional selection. In the absence of mutation, the potential effect of directional selection is bounded. Read on >>

  • Appendix B: Modes of polyploid production. Polyploids arise in more than one way. Read on >>

  • Appendix C: Zygotic doubling. Zygotic doubling is an additional way in which polyploidy can arise. Read on >>

  • Appendix D: Rates of aneuploid production. Rates of aneuploid production are not easy to ascertain. Read on >>

  • Appendix E: H. J. Muller and polyploidy. H. J. Muller led many biologists to dismiss the possibility of polyploid animals. Read on >>

  • Appendix F: Recombinational stabilization (theoretical considerations). A discussion of the theoretical aspects of recombinational stabilization. Read on >>

  • Appendix G: Underreporting of hybridization. Hybridization is underreported for a variety of reasons. Read on >>

  • Appendix H: Darwin's assessment of hybridization. Darwin eventually came to attach more significance to the evolutionary potential of hybridization than his writings in the Origin indicate. Read on >>

  • Appendix I: Stability of sexual chromosets. Reasons for the stability of sexual chromosets. Read on >>

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