Precambrian rabbit

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"Precambrian rabbits" or "fossil rabbits in the Precambrian" are reported to have been among responses given by the biologist J. B. S. Haldane when asked what evidence could destroy his confidence in the theory of evolution and the field of study. The answers became popular imagery in debates about evolution and the scientific field of evolutionary biology in the 1990s. Many of Haldane's statements about his scientific research were popularized in his lifetime.

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Some accounts use this response to rebut claims that the theory of evolution is not falsifiable by any empirical evidence. This follows an assertion by Karl Popper, a philosopher of science who proposed that falsifiability is an essential feature of a scientific theory. Popper also expressed doubts about the scientific status of evolutionary theory,[ citation needed ] although he later concluded that the field of study was genuinely scientific.[ citation needed ]

Rabbits are mammals. From the perspective of the philosophy of science, it is doubtful whether the genuine discovery of mammalian fossils in Precambrian rocks would overthrow the theory of evolution instantly, though if authentic, such a discovery would indicate serious errors in modern understanding about the evolutionary process. Mammals are a class of animals whose emergence in the geologic timescale is dated to much later than any found in Precambrian strata. Geological records indicate that although the first true mammals appeared in the Triassic period, modern mammalian orders appeared in the Palaeocene and Eocene epochs of the Palaeogene period. Hundreds of millions of years separate this period from the Precambrian.

Origin of the phrase

Several authors have written that J. B. S. Haldane (1892–1964) said that the discovery of a fossil rabbit in Precambrian rocks would be enough to destroy his belief in evolution. [1] [2] [3] [4] [5] [6] However these references date from the 1990s or later. In 1996 Michael J. Benton cited the 1993 edition of Mark Ridley's book Evolution, [7] Evolutionary biologist Richard Dawkins wrote in 2005 that Haldane was responding to a challenge by a "Popperian zealot". [6] In 2004 Richa Arora wrote that the story was told by John Maynard Smith (1920–2004) in a television programme. [8] John Maynard Smith attributed the phrase to Haldane in a conversation with Paul Harvey in the early 1970s.

Theoretical background

The philosopher Karl Popper held that any scientific proposition must be falsifiable, in other words it must at least be possible to imagine some reproducible experiment or observation whose outcome would disprove the hypothesis. [9] Initially he thought that Charles Darwin's theory of natural selection (often summarized as "the survival of the fittest" [10] ) was untestable in this sense, and therefore "almost tautological." [7] Popper later changed his view, concluding that the theory of natural selection is falsifiable and that Darwin's own example of the peacock's tail had disproved one extreme variation of it, that all evolution is driven by natural selection. [11] Although in 1978 Popper wrote that his earlier objection had been specifically to the theory of natural selection, in lectures and articles from 1949 to 1974 he had stated that "Darwinism" or "Darwin's theory of evolution" was a "metaphysical research programme" because it was not falsifiable. [12] In fact he continued to express dissatisfaction with contemporary statements of the theory of evolution which focused on population genetics, the study of the relative frequencies of alleles (different forms of the same gene). Unfortunately some of the adjustments he proposed resembled Lamarckianism or saltationism, evolutionary theories that were and still are considered obsolete, and evolutionary biologists therefore disregarded his criticisms. [9] In 1981 Popper complained that he had been misinterpreted as saying that "historical sciences" such as paleontology or the history of evolution of life on Earth were not genuine sciences, when in fact he believed they could make falsifiable predictions. [9] [13]

Further confusion arose in 1980–1981, when there was a long debate in the pages of Nature about the scientific status of the theory of evolution. [14] [15] Specifically, the argument was on the factors influencing and nature of the unit of selection in the genome, with one side positing natural selection, [16] [17] and the other, neutral mutation. [18] [19] Neither of the parties seriously doubted that the theory was both scientific and, according to current scientific knowledge, true. Some participants objected to statements that appeared to present the theory of evolution as an absolute dogma, however, rather than as a hypothesis that so far has performed very well, and both sides quoted Popper in support of their positions. Evolution critics such as Phillip E. Johnson took this as an opportunity to declare that the theory of evolution was unscientific. [9] [15]

Would anachronistic fossils disprove evolution?

Richard Dawkins said that the discovery of fossil mammals in Precambrian rocks would "completely blow evolution out of the water." [20] Philosopher Peter Godfrey-Smith doubted that a single set of anachronistic fossils, however, even rabbits in the Precambrian, would disprove the theory of evolution outright. The first question raised by the assertion of such a discovery would be whether the alleged "Precambrian rabbits" really were fossilized rabbits. Alternative interpretations might include incorrect identification of the "fossils", incorrect dating of the rocks, and a hoax such as the Piltdown Man was shown to be. Even if the "Precambrian rabbits" turned out to be genuine, they would not instantly refute the theory of evolution, because that theory is a large package of ideas, including: that life on Earth has evolved over billions of years; that this evolution is driven by certain mechanisms; and that these mechanisms have produced a specific "family tree" that defines the relationships among species and the order in which they appeared. Hence, "Precambrian rabbits" would prove that there were one or more serious errors somewhere in this package, and the next task would be to identify those errors. [2]

Benton pointed out that, in the short term, scientists often have to accept the existence of competing hypotheses, each of which explains large parts—but not all—of the observed relevant data. [7]

Oldest rabbit

Genuine fossils of earliest rabbits are from the Eocene Epoch, about 56 million years to 33.9 million years ago. Members of the genus Gomphos are established to be the phylogenetic root of lagomorph rabbits and hares. [21] To date, the oldest Gomphos is G. elkema discovered in 2008 from Gujarat, India. The fossil is dated to 53 million years old. [22] [23]

See also

Related Research Articles

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<span class="mw-page-title-main">Evolution</span> Change in the heritable characteristics of biological populations

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<span class="mw-page-title-main">Falsifiability</span> Property of a statement that can be logically contradicted

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<span class="mw-page-title-main">John Maynard Smith</span> English biologist and geneticist (1920–2004)

John Maynard Smith was a British theoretical and mathematical evolutionary biologist and geneticist. Originally an aeronautical engineer during the Second World War, he took a second degree in genetics under the well-known biologist J. B. S. Haldane. Maynard Smith was instrumental in the application of game theory to evolution with George R. Price, and theorised on other problems such as the evolution of sex and signalling theory.

<span class="mw-page-title-main">Natural selection</span> Mechanism of evolution by differential survival and reproduction of individuals

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The modern synthesis was the early 20th-century synthesis of Charles Darwin's theory of evolution and Gregor Mendel's ideas on heredity into a joint mathematical framework. Julian Huxley coined the term in his 1942 book, Evolution: The Modern Synthesis. The synthesis combined the ideas of natural selection, Mendelian genetics, and population genetics. It also related the broad-scale macroevolution seen by palaeontologists to the small-scale microevolution of local populations.

<span class="mw-page-title-main">Transitional fossil</span> Type of fossilized remains

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<span class="mw-page-title-main">Group selection</span> Proposed mechanism of evolution

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<span class="mw-page-title-main">Unit of selection</span> Biological entity within the hierarchy of biological organization

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Objections to evolution have been raised since evolutionary ideas came to prominence in the 19th century. When Charles Darwin published his 1859 book On the Origin of Species, his theory of evolution initially met opposition from scientists with different theories, but eventually came to receive overwhelming acceptance in the scientific community. The observation of evolutionary processes occurring has been uncontroversial among mainstream biologists since the 1940s.

The Cambrian explosion, Cambrian radiation,Cambrian diversification, or the Biological Big Bang refers to an interval of time approximately 538.8 million years ago in the Cambrian Period of early Paleozoic when there was a sudden radiation of complex life and practically all major animal phyla started appearing in the fossil record. It lasted for about 13 – 25 million years and resulted in the divergence of most modern metazoan phyla. The event was accompanied by major diversification in other groups of organisms as well.

<span class="mw-page-title-main">History of evolutionary thought</span>

Evolutionary thought, the recognition that species change over time and the perceived understanding of how such processes work, has roots in antiquity—in the ideas of the ancient Greeks, Romans, Chinese, Church Fathers as well as in medieval Islamic science. With the beginnings of modern biological taxonomy in the late 17th century, two opposed ideas influenced Western biological thinking: essentialism, the belief that every species has essential characteristics that are unalterable, a concept which had developed from medieval Aristotelian metaphysics, and that fit well with natural theology; and the development of the new anti-Aristotelian approach to modern science: as the Enlightenment progressed, evolutionary cosmology and the mechanical philosophy spread from the physical sciences to natural history. Naturalists began to focus on the variability of species; the emergence of palaeontology with the concept of extinction further undermined static views of nature. In the early 19th century prior to Darwinism, Jean-Baptiste Lamarck (1744–1829) proposed his theory of the transmutation of species, the first fully formed theory of evolution.

The Extended Evolutionary Synthesis (EES) consists of a set of theoretical concepts argued to be more comprehensive than the earlier modern synthesis of evolutionary biology that took place between 1918 and 1942. The extended evolutionary synthesis was called for in the 1950s by C. H. Waddington, argued for on the basis of punctuated equilibrium by Stephen Jay Gould and Niles Eldredge in the 1980s, and was reconceptualized in 2007 by Massimo Pigliucci and Gerd B. Müller.

<span class="mw-page-title-main">History of speciation</span> Aspect of history

The scientific study of speciation — how species evolve to become new species — began around the time of Charles Darwin in the middle of the 19th century. Many naturalists at the time recognized the relationship between biogeography and the evolution of species. The 20th century saw the growth of the field of speciation, with major contributors such as Ernst Mayr researching and documenting species' geographic patterns and relationships. The field grew in prominence with the modern evolutionary synthesis in the early part of that century. Since then, research on speciation has expanded immensely.

References

  1. ↑ Mark Ridley (2004). Evolution. Blackwell Publishing. p. 66. ISBN   978-1-4051-0345-9 . Retrieved 2008-10-28.
  2. 1 2 Peter Godfrey-Smith (2003). Theory and Reality: An Introduction to the Philosophy of Science. University of Chicago Press. pp. 72–74. ISBN   978-0-226-30062-7 . Retrieved 2008-10-28.
  3. ↑ Benton, M.J. (1996). "Testing the Time Axis of Phylogenies". In Harvey, P.H.; Brown, A.J.L.; Smith, J.M.; Nee, S. (eds.). New Uses for New Phylogenies. Oxford University Press. p. 222. ISBN   978-0-19-854984-0 . Retrieved 2008-10-28.
  4. ↑ Lane, N. (2005). Power, Sex, Suicide: Mitochondria and the Meaning of Life . Oxford University Press. p.  271. ISBN   978-0-19-280481-5 . Retrieved 2008-10-28. haldane precambrian rabbit.
  5. ↑ Greener, M. (2007). "Taking on creationism. Which arguments and evidence counter pseudoscience?". EMBO Reports. 8 (12): 1107–1109. doi:10.1038/sj.embor.7401131. PMC   2267227 . PMID   18059309.
  6. 1 2 Dawkins, R. (November 2005). "The Illusion of Design". Natural History Magazine. Retrieved 2010-11-15.
  7. 1 2 3 Benton, M.J. & Hitchin, R. (1996). "Testing the Quality of the Fossil Record by Groups and by Major Habitats" (PDF). Historical Biology. 12 (2): 111–157. doi:10.1080/08912969609386559 . Retrieved 2008-10-28.
  8. ↑ Arora, R. (2004). Encyclopaedia of Evolutionary Biology. Anmol Publications. p. 18. ISBN   978-81-261-1500-6 . Retrieved 2008-10-28.
  9. 1 2 3 4 Hull, D.L. (October 1999). "The Use and Abuse of Sir Karl Popper". Biology and Philosophy. 14 (4): 481–504. doi:10.1023/A:1006554919188. S2CID   170432732.
  10. ↑ "This preservation of favourable individual differences and variations, and the destruction of those which are injurious, I have called Natural Selection, or the Survival of the Fittest." —Charles Robert Darwin. (2001). "IV. Natural Selection; or the Survival of the Fittest". In Charles W. Eliot (ed.). The origin of species. Bartleby.com.{{cite book}}: |work= ignored (help)
  11. ↑ Popper, K. (1978). "Natural Selection and the Emergence of Mind". Dialectica. 32 (3–4): 339–355. doi:10.1111/j.1746-8361.1978.tb01321.x.
  12. ↑ Popper, K. (2002). "Darwinism as a Metaphysical Research Programme". In Balashov, Y.; Rosenberg, A. (eds.). Philosophy of science: Contemporary Readings. Routledge. pp. 302–304. ISBN   978-0-415-25781-7 . Retrieved 2008-10-28.
  13. ↑ Popper, K.R. (1981). "Evolution". New Scientist. 87: 611.
  14. ↑ Editorial (1981). "How true is the theory of evolution?". Nature. 290 (5802): 75–76. Bibcode:1981Natur.290...75.. doi:10.1038/290075a0. PMID   7207599. S2CID   5085752.
  15. 1 2 Johnson PE (2010). Darwin on Trial. InterVarsity Press. p. 238. ISBN   9780830838318.
  16. ↑ Orgel LE, Crick FH (1980). "Selfish DNA: the ultimate parasite". Nature. 284 (5757): 604–607. Bibcode:1980Natur.284..604O. doi:10.1038/284604a0. PMID   7366731. S2CID   4233826.
  17. ↑ Cavalier-Smith T (1980). "How selfish is DNA?". Nature. 285 (5767): 617–618. Bibcode:1980Natur.285..617C. doi: 10.1038/285617a0 . PMID   7393317. S2CID   27111068.
  18. ↑ Dover G, Doolittle WF (1980). "Modes of genome evolution". Nature. 288 (5792): 646–647. Bibcode:1980Natur.288..646D. doi: 10.1038/288646a0 . PMID   6256636. S2CID   8938434.
  19. ↑ Li WH, Gojobori T, Nei M (1981). "Pseudogenes as a paradigm of neutral evolution". Nature. 292 (5820): 237–239. Bibcode:1981Natur.292..237L. doi:10.1038/292237a0. PMID   7254315. S2CID   23519275.
  20. ↑ Wallis, C. (August 7, 2005). "The Evolution Wars". Time. Archived from the original on October 13, 2007. Retrieved 2008-10-29.
  21. ↑ Asher RJ, Meng J, Wible JR, McKenna MC, Rougier GW, Dashzeveg D, Novacek MJ (2005). "Stem Lagomorpha and the antiquity of Glires". Science. 307 (5712): 1091–1094. Bibcode:2005Sci...307.1091A. doi:10.1126/science.1107808. PMID   15718468. S2CID   42090505.
  22. ↑ Rose KD, DeLeon VB, Missiaen P, Rana RS, Sahni A, Singh L, Smith T (2008). "Early Eocene lagomorph (Mammalia) from Western India and the early diversification of Lagomorpha". Proc Biol Sci. 275 (1639): 1203–1208. doi:10.1098/rspb.2007.1661. PMC   2602686 . PMID   18285282.
  23. ↑ National Geographic News (21 March 2008). "Easter Surprise: World's Oldest Rabbit Bones Found". National Geographic Society. Archived from the original on 18 February 2014. Retrieved 2 August 2013.
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