Transitional form

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Tiktaalik, a species of extinct sarcopterygian fish.

A transitional form is a living or fossilized organism that is believed to be an evolutionary link between two distinct groups (also referred to as intermediates or missing links). This is suggested when the organism possesses characteristics that uniquely belong to different taxa, or when fossils exhibit traits that are considered primitive in comparison to living varieties.[1] For example, the Tiktaalik is thought by evolutionists to be an intermediate between fish and reptiles because it has fleshy fins, and thus one believes that the fins enabled it to evolve from shallow waters to life on land.

When we examine living populations, there is a clear distinction between various plants and animals, which has allowed us to classify them into taxonomic groups. Since evolution via random mutations must occur at an extremely slow and gradual rate, we should find a continuous series of intermediate fossils that illustrate the transition from one type of organism to another if this theory is valid. The sheer absence of these transitional forms is the most reiterated empirical evidence against evolution. In this arena quotes from honest evolutionists are numerous decrying the state of the fossil record. For example David B. Kitts of the School of Geology and Geophysics at the University of Oklahoma wrote: "Evolution requires intermediate forms between species and paleontology does not provide them…".[2]

The evolutionist Michael Denton also acknowledges this irrefutable problem.

The fact that so many of the founders of modern biology, those who discovered all the basic facts of comparative morphology upon which modern evolutionary biology is based, held nature to be fundamentally a discontinuum of isolated and unique types unbridged by transitional varieties, a position absolutely at odds with evolutionary ideas, is obviously very difficult to reconcile with the popular notion that all the facts of biology irrefutably support an evolutionary interpretation.[3]

To nearly all of the great biologists and naturalists of the late eighteenth and early nineteenth centuries, Darwin's theory failed to explain the discontinuity of species. Instead a typological model was adhered to, which recognized that organisms exist as distinct types.[4] To explain the absence of transitional forms, an uncharacterized macroevolution process was proposed as being responsible for the rapid saltation (evolutionary jumps) responsible for the gaps between taxa, with the traditional micro process operating to produce the slow and gradual change responsible for groups of similar species.

Absence of fossil forms

There are over one hundred million identified and catalogued fossils currently in the world's museums.[5] If all life on Earth has descended from a single common ancestor then there should be countless "transitional forms" in the fossil record that show the gradual transformation of organisms. Compared to the number of living and fossil organisms, transitional forms are conspicuously absent and often referred to simply as "missing links".

Evolutionist Michael Denton stated:

It is still, as it was in Darwin's day, overwhelmingly true that the first representatives of all the major classes of organisms known to biology are already highly characteristic of their class when they make their initial appearance in the fossil record. This phenomenon is particularly obvious in the case of the invertebrate fossil record. At its first appearance in the ancient paleozoic seas, invertebrate life was already divided into practically all the major groups with which we are familiar today.[6]

If Biblical young earth creationism is true then this precisely what should be found. The creationist view predicts the presence of distinct kinds of animal with no transitionals between; or at best a handful of disputed forms. Evolutionists have spent over 140 years trying to find transitional fossils and nothing approaching a conclusive form has ever been found - only a handful of doubtful examples exist.[7][8]

Noted anthropologist Edmund Ronald Leach stated:

Missing links in the sequence of fossil evidence were a worry to Darwin. He felt sure they would eventually turn up, but they are still missing and seem likely to remain so.[9]

David Raup, who was the curator of geology at the museum holding the world's largest fossil collection (the Field Museum of Natural History in Chicago), observed: "[Darwin] was embarrassed by the fossil record because it didn't look the way he predicted it would.... Well, we are now about 120 years after Darwin, and knowledge of the fossil record has been greatly expanded. We now have a quarter of a million fossil species but the situation hasn't changed much.... [W]e have even fewer examples of evolutionary transition than we had in Darwin's time." (David M. Raup, "Conflicts Between Darwin and Paleontology," Field Museum of Natural History Bulletin 50 (January 1979): 22-23, 24-25)

One of the most famous proponents of evolution was the late Harvard paleontologist Stephen Jay Gould. But Gould admitted, "The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology. We fancy ourselves as the only true students of life’s history, yet to preserve our favored account of evolution by natural selection, we view our data as so bad that we never see the very process we profess to study.[10] In a 1977 paper titled "The Return of Hopeful Monsters", Gould wrote: "All paleontologists know that the fossil record contains precious little in the way of intermediate forms; transitions between major groups are characteristically abrupt."[11]

The senior paleontologist at the British Museum of Natural History, Dr. Colin Patterson, put it this way: "Gould and the American Museum people are hard to contradict when they say there are no transitional fossils."[12]

Evolutionist views

Evolutionists present several transition series. They are based on a comparison of selected parts, while often ignoring bigger differences. Sometimes the various types are represented only by fragmented fossil evidence. Often they will use what are called cousins when they can not find a fossil in the right place to be able to call it an ancestor. The gaps recognized by evolutionists are often at critical parts in the fossil record. Jonathan Sarfati comments:

"Many of the alleged transitional forms are based on fragmentary remains, which are therefore open to several interpretations, based on one’s axioms. Evolutionary bias means that such remains are often likely to be interpreted as transitional, as with Gingerich, and is also prevalent in ape-man claims. But when more bones are discovered, then the fossils nearly always fit one type or another, and are no longer plausible as transitional. It’s also notable that alleged intermediate forms are often trumpeted in the media, while retractions are usually muted or unpublicized."[13]

Often the designation of a new genus or species is based on only one individual or at most only a few individuals. In such cases they may represent a small number of degenerative mutants, rather than an entire genus or species. This would greatly reduce the number of individuals implied by the fossil record.

Darwin's Concerns

Charles Darwin himself stated that evolutionary theory required the existence of "transitional forms." Darwin wrote: "So that the number of intermediate and transitional links, between all living and extinct species, must have been inconceivably great. But assuredly, if this theory be true, such have lived upon the earth." [14]

The lack of transitional forms was one of the four prominent weaknesses to his theory that Darwin puzzled over in "On the Origin of Species," and indeed devoted an entire chapter of the book (IV: On the Imperfection of the Fossil Record)[15] to what he acknowledged was a serious danger to his theory:

"In the four succeeding chapters, the most apparent and gravest difficulties on the theory will be given: namely, first, the difficulties of transitions, or in understanding how a simple being or a simple organ can be changed and perfected into a highly developed being or elaborately constructed organ; secondly, the subject of Instinct, or the mental powers of animals; thirdly, Hybridism, or the infertility of species and the fertility of varieties when intercrossed; and fourthly, the imperfection of the Geological Record." (p. 6)[16]
"Long before having arrived at this part of my work, a crowd of difficulties will have occurred to the reader. Some of them are so grave that to this day I can never reflect on them without being staggered; but, to the best of my judgment, the greater number are only apparent, and those that are real are not, I think, fatal to my theory.

These difficulties and objections may be classed under the following heads:—

Firstly, why, if species have descended from other species by insensibly fine gradations, do we not everywhere see innumerable transitional forms? Why is not all nature in confusion instead of the species being, as we see them, well defined?

Secondly, is it possible that an animal having, for instance, the structure and habits of a bat, could have been formed by the modification of some animal with wholly different habits? Can we believe that natural selection could produce, on the one hand, organs of trifling importance, such as the tail of a giraffe, which serves as a fly-flapper, and, on the other hand, organs of such wonderful structure, as the eye, of which we hardly as yet fully understand the inimitable perfection?

Thirdly, can instincts be acquired and modified through natural selection? What shall we say to so marvellous an instinct as that which leads the bee to make cells, which have practically anticipated the discoveries of profound mathematicians?

Fourthly, how can we account for species, when crossed, being sterile and producing sterile offspring, whereas, when varieties are crossed, their fertility is unimpaired?"(pp. 171-172)[17]

Further, Darwin wrote: "Why then is not every geological formation and every strata full of such intermediate links? Geology assuredly does not reveal any such finely-graduated organic chain; and this perhaps, is the most obvious and serious objection which can be urged against my theory." [18] Darwin thought the lack of transitional links in his time was because

only a small portion of the surface of the earth has been geologically explored and no part with sufficient care...".[19]

Darwin's theory of evolution required that transitional forms exist. As Charles Darwin became older, however, he became increasingly concerned about this lack of evidence in regards to the fossil record. Darwin wrote,

When we descend to details, we cannot prove that a single species has changed; nor can we prove that the supposed changes are beneficial, which is the groundwork of the theory.[20]

Disputed Existence

{{line-height|1|Some evolutionists aver that transitional forms exist, but that is certainly not the consensus. The eminent Pierre Grasse, editor of the 28 volume Traite de Zoologie, one-time president of the Academie des Science attacked modern evolution theory on the grounds that it assumed to know much more than it did. Stephen Jay Gould in an often quoted statement calls the lack of transitional forms the "trade secret" in paleontology. It should be noted that this statement was made not in an effort to support creationism, but rather an explanation of why he felt the need to design a different theory to accommodate this absence.

The California University evolutionist biologist James W. Valentine makes this confession in What Darwin Began:

The fossil record is of little use in providing direct evidence of the pathways of descent of the phyla or of invertebrate classes. Each phylum with a fossil record had already evolved its characteristic body plan when it first appeared, so far as we can tell from the fossil remains, and no phylum is connected to any other via intermediate fossil types. Indeed, none of the invertebrate classes can be connected with another class by series of intermediates.[21]

Colin Patterson, senior paleontologist at the British Museum of Natural History, wrote to a reader in 1979 the following passage:

I fully agree with your commentary on the lack of evolutionary transitions in my book. If I knew of any, fossil or living, I would have certainly included them. I will lay it on the line, there is not one such fossil for which one could make a watertight argument.

It is claimed that Patterson asked the assemblage of paleontologists at a 1998 conference whether anyone knew of a genuine transitional form, receiving no answer but silence. This report is only partially substantiated.

Punctuated Equilibrium

Main Article: Punctuated equilibrium

The lack of support from the fossil record and the dearth of transitional forms composing a reasonably minimum continuum is something recognized by some evolutionists themselves. Evolutionists have dealt with this concern in two divergent ways. Some have decided that evolution is simply a postulate which must be believed due to lack of reasonable alternatives.

Others, such as Stephen Jay Gould, have claimed that evolution does not take place in small gradual steps. Rather, he and others believe that evolution may take place in small populations for short bursts of time before a plateau is reached. This means that transitional forms would be few in number because they only exists in small populations for small lengths of time. Gould has used the absence of transitionals in support of his own evolutionary theory of "punctuated equilibrium", and as evidence against the "gradualism" that Charles Darwin expected.[22] Not surprisingly, many critics of evolution view "punctuated equilibrium" as simply an excuse for the absence of fossil evidence.[23][24]

The theory of punctuated equilibrium is discussed in great detail at Talk.Origins[25]; it became a major rival to Neo-Darwinism in the latter part of the 20th century.

Reputed transitionals

Archaeopteryx fossil.

Archaeopteryx

Main Article: Archaeopteryx

One of the more famous alleged transitional fossils claimed by evolutionists is Archaeopteryx. Dr. Alan Feduccia, a world authority on birds and an evolutionist himself, has stated the following regarding Archaeopteryx:

Paleontologists have tried to turn Archaeopteryx into an earth-bound, feathered dinosaur. But it’s not. It is a bird, a perching bird. And no amount of ‘paleobabble’ is going to change that. [26]

Creationist scientists have a number of arguments against Archaeopteryx being a transitional fossil find.[26][27][28][29]

Tiktaalik

Main Article: Tiktaalik

A second famous alleged transitional fossil claimed by evolutionists is Tiktaalik. Creationists have a number of arguments regarding the fossil find of Tiktaalik not being a transitional find.[30][31]

Ape men

Main Article: Human evolution
Main Article: Recent controversy in hominid ancestry

Over the past decade, a series of controversies have engulfed evolutionary theory, as an array of fossil discoveries have provided new knowledge on the human fossil record. However, these discoveries have been so controversial as to require even major publications to begin acknowledging, first in 2001 after the discovery of O. tugenensis, and climaxing in 2007 with the discovery that H. habilis and H. erectus coexisted, that the human evolutionary tree now looks like a "bush with many branches". One after another of the species previously labeled "missing links," ancestors of modern humans, have been conceded to be "offshoots" because of early complexity, as they are discovered to walk upright, coexist with other hominins, or prove similar to modern humans, rather than showing early similarity to apes.[Reference needed]

Composite Human Fossil Chart. Illustrates the comparable dates assigned to Homo erectus, anatomically modern Homo sapiens, Neanderthals, and Early African/Asian Homo sapiens. Also shown are Australopithecus and Homo habilis..[32]

A number of recently discovered species, which were supposed to be linear descendants of one another, were determined to actually coexist, and thus couldn't have evolved from one another. Homo erectus and Homo habilis both coexisted, Australopithecus afarensis (Lucy) and Australopithecus ramidus (Ardi) also both coexisted, and some brand new fossils were found to coexist with modern humans and Neanderthals, like Homo floresiensis ('Hobbit Man') and the Denisovans. Jonathan Sarfati reports on Marvin Lubenow's research that was published in Bones of Contention:

Marvin Lubenow shows that the various alleged ‘apemen’ do not form a smooth sequence in evolutionary ‘ages,’ but overlap considerably. For example, the timespan of Homo sapiens fossils contains the timespan of the fossils of Homo erectus, supposedly our ancestor. Also, when the various fossils are analyzed in depth, they turn out not to be transitional or even mosaic. The morphology overlaps too—the analysis of a number of characteristics indicates that Homo ergaster, H. erectus, H. neanderthalensis as well as H. heidelbergensis, were most likely ‘racial’ variants of modern man, while H. habilis and another specimen called H. rudolfensis were just types of australopithecines. In fact, H. habilis is now regarded as an invalid name, probably caused by assigning fragments of australopithecines and H. erectus fossils into this ‘taxonomic waste bin.’[13]

According to Encyclopaedia Britannica, current dating of Australopiths, Ar. kaddaba and Ar. ramidus coexisted; A. afarensis, K. platyops, A. bahrelgazali, and A. africanus all coexisted; P. aethiopicus, A. africanus, A. garhi, H. habilis, and H. rudolfensis all coexisted; and A. sediba, P. boisei, H. rudolfensis, and H. habilis all coexisted as well.[33] A large number of hominins therefore coexisted and thus are 'offshoots' which could not have evolved from one another, resulting in a messy 'bush'. Rather than a nice orderly tree progression, they're living at the same times. Instead of having descended from one another, scientists now use the term offshoots, since as famous paleontologist Meave Leakey has noted, "Their co-existence makes it unlikely that Homo erectus evolved from Homo habilis.".[34]

A new discovery suggests that Homo erectus may not have evolved from Homo habilis—and that the two may have been contemporaries. The phrase 'family bush' doesn't trip off the tongue the way 'family tree' does, but anyone talking about human evolution had better get used to it. For years, scientists who study human origins have known that the simple model in which one human ancestor evolved into another in a nice, linear fashion is a myth. Instead, starting 4 million years ago, half a dozen species in the genus Australopithecus lived in Africa at the same time. Only one is our direct ancestor; the others were evolutionary dead ends, failed experiments. But experts thought that once the Homo lineage debuted about 2.5 million years ago in East Africa with Homo habilis, things settled down, with habilis evolving into Homo erectus who evolved into Homo sapiens—us—like biblical begats. Two fossils discovered in Kenya suggest that evolution was a lot messier than that. (Newsweek 2007)[35]

A number of new hominids have been discovered that are causing additional trouble for evolutionary theory. Sahelanthropus tchadensis, Orrorin tugenensis, and Ardipithecus ramidus (Ardi) now make for our three oldest hominin fossils. Trouble is, they are way too human-like, showing far more early complexity and similarity to modern humans, including evidence of early bipedalism, than was supposed to exist so far back in the human lineage. The discovery of such early bipedalism then led to the claim that A. afarensis (Lucy) and A. sediba also walked upright.[Reference needed] The prevailing theory that humans share a common ancestor with chimpanzees is also in question due to recent research which revealed that the majority of Australopithecines and Habilines are more closely aligned with orangutans. This leaves humans without a plausible ancestor.[36]In addition, a chimp was discovered in 2005 that revealed that chimps lived east of the Rift Valley, which would play a role in the eventual abandonment of the famous Savannah Hypothesis that humans evolved without chimps because of leaving the African jungles for the savannahs (since chimps also left).[Reference needed]

Another discovery by Dr. Leakey challenged the prevailing view that the family tree had a more or less single trunk rising from ape roots to a pinnacle occupied by Homo sapiens. Yet here was evidence that the new species Kenyanthropus platyops co-existed with Lucy’s afarensis kin. The family tree now looks more like a bush with many branches. 'Just because there’s only one human species around now doesn't mean it was always that way,' Dr. Grine said... Two even earlier specimens are even harder to interpret. One found in Kenya by a French team has been dated to six million years and named Orrorin tugenensis. The teeth and bone pieces are few, though the discoverers think a thigh fragment suggests that the individual was a biped — a walker on two legs. Another French group then uncovered 6.7-million-year-old fossils in Chad. Named Sahelanthropus tchadensis, the sole specimen includes only a few teeth, a jawbone and a crushed cranium... Other challenges arise from human evolution in more recent epochs. Just who were the 'little people' found a few years ago in a cave on the island of Flores in Indonesia? The Australian and Indonesian discoverers concluded that one partial skeleton and other bones belonged to a now-extinct separate human species, Homo floresiensis, which lived as recently as 18,000 years ago. (New York Times 2007) [37]
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References

  1. "Transitional Forms." Understanding Evolution. University of California Museum of Paleontology.
  2. Kitts DB, cited at "15 Answers to John Rennie and Scientific American's Nonsense, Argument 13," Thompson B and Harrub B, eds. Apologetics Press, n.d. Accessed October 21, 2008.
  3. Denton, Michael. Evolution: A Theory in Crisis, 3rd rev. ed. Adler & Adler. 1986 (ISBN 978-0917561528), p. 100.
  4. Denton, op. cit., p. 99.
  5. "Scientists Speak About Fossils." Creation-Evolution Encyclopedia, Pathlights. Accessed October 21, 2008.
  6. Denton, op. cit., p. 162
  7. "Get Answers: Fossils." Answers in Genesis, n.d. Accessed October 21, 2008.
  8. "Fossils Questions and Answers." Creation Ministries International, n.d. Accessed October 21, 2008.
  9. Leach E. "Still Missing After All These Years." Evolution is Dead!, 2008 Accessed October 21, 2008.
  10. Gould SJ, cited at "15 Answers to John Rennie and Scientific American's Nonsense, Argument 5," Thompson B and Harrub B, eds. Apologetics Press, n.d. Accessed October 21, 2008.
  11. Batten D. "Punctuated equilibrium: come of age?" TJ 8(2):131-137, August 1994. Accessed October 21, 2008.
  12. "Those fossils are a problem." Creation 14(4):44-45, September 1992. Accessed October 21, 2008.
  13. 13.0 13.1 Sarfati, Jonathan. Refuting Evolution 2 Chapter 8 - Argument: The fossil record supports evolution. Greenforest AR: Master Books, 2002. (p136-137) Cite error: Invalid <ref> tag; name "refuting2" defined multiple times with different content
  14. Foard JM. "Fossils: History Written in Stone." The Darwin Papers, 1(5), 1996. Accessed October 21, 2008.
  15. Darwin, C.R. On the Origin of Species, 1st ed. London 1859, p. 280.
  16. Darwin, C.R. On the Origin of Species, 1st ed. London 1859, p. 6.
  17. Darwin, C.R. On the Origin of Species, 1st ed. London 1859, pp. 171-172.
  18. "Natural Discontinuities and the Fossil Record." Veritas Forum, University of California at Santa Barbara, n.d. Accessed October 21, 2008.
  19. Darwin C. "Chapter X: On the Imperfection of the Fossil Record." The Origin of Species, hosted at The Complete Works of Charles Darwin. Accessed October 21, 2008.
  20. Darwin, C. The Life and Letters of Charles Darwin, vol. 1, p. 120. Cited at "References and Notes: Distinct Types," In the Beginning: Compelling Evidence for the Creation and the Flood by Walt Brown, 2008. Accessed October 21, 2008.
  21. What Darwin Began: Modern Darwinism and Non-Darwinist Perspectives, L.R. Godfrey, Ed., Allyn & Bacon Inc. 1985 p. 263.
  22. Gould, S.J. & Eldredge, N. (1972). "Punctuated equilibria: An alternative to phyletic gradualism." In Schopf, Thomas, J.M. (ed.). Models in Paleobiology. Freeman, Cooper and Company, San Francisco, pp. 82-115.
  23. Batten, D. (1994, August). "Punctuated equilibrium: Come of age?" In Journal of Creation, 8(2):131-137.
  24. Scott, Heidi (2007). "Stephen Jay Gould and the Rhetoric of Evolutionary Theory". Rhetoric Review 26 (2): 120–141.
  25. "Punctuated Equilibria." Talk.Origins, n.d. Accessed October 21, 2008.
  26. 26.0 26.1 Sarfati J. "Archaeopteryx (unlike Archaeoraptor) is NOT a hoax—it is a true bird, not a 'missing link'." Answers in Genesis, 24 March 2000. Accessed October 21, 2008.
  27. Wieland C. "Archaeopteryx." Ex Nihilo 1(1):12-16, June 1978. Accessed October 21, 2008.
  28. Gish D. "As a Transitional Form Archaeopteryx Won't Fly." Institute for Creation Research, Impact 321, September 1989. Accessed October 21, 2008.
  29. Sarfati J. "Chapter 4: Bird Evolution?" In Refuting Evolution. Accessed October 21, 2008.
  30. Sarfati J. "Tiktaalik roseae—a fishy 'missing link'." Creation Ministries International, April 15, 2006. Accessed October 21, 2008.
  31. Sherwin F. "Tiktaalik: Our Ancestor?" Institute for Creation Research, Impact 2962, April 2006. Accessed October 21, 2008.
  32. Lubenow, Marvin. Bones of Contention: A Creationist Assessment of Human Fossils. Grand Rapids, MI: Baker Books, 1992. p. 336
  33. "Australopithecus." Encyclopædia Britannica. Encyclopædia Britannica Online. Encyclopædia Britannica Inc., 2012. Web. 15 Apr. 2012. <http://www.britannica.com/EBchecked/topic/44115/Australopithecus>.
  34. Urquhart, James (2007, August 8).Finds Test Human Origins Theory. BBC News.
  35. Begley, Sharon L. (2007, August 7).The Human Family Shrub?. Newsweek.
  36. Humans related to orangutans, not chimps PhysOrg.com, June 18, 2009.
  37. Wilford, John (2007, June 26). The Human Family Tree Has Become a Bush With Many Branches. New York Times.

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