Changes

A '''transitional form''' is a [[fossil]] or living [[organism]] that is intermediate between two other organism in an evolutionary sequence.

A '''transitional form''' is a [[fossil]] or living [[organism]] that is intermediate between two other organism in an evolutionary sequence.

A transitional form that has not yet been found is colloquially called a '[[missing link]]'.

A transitional form that has not yet been found is colloquially called a '[[missing link]]'.

[[Creationist]]s claim that transitional forms between different kinds of creatures are systematically absent.

[[Creationist]]s claim that transitional forms between different kinds of creatures are systematically absent.

Most scientists typically reject this claim. One such rebuttal is that by [[Kathleen Hunt]] who created a Transitional Vertebrate Fossil FAQ.<ref>Hunt, Kathleen, [http://www.talkorigins.org/faqs/faq-transitional.html] (Talk.Origins)</ref>

Other scientists typically reject this claim. One such attempted rebuttal is that by [[Kathleen Hunt]] who created a Transitional Vertebrate Fossil FAQ.<ref>Hunt, Kathleen, [http://www.talkorigins.org/faqs/faq-transitional.html Transitional Vertebrate Fossils FAQ] (Talk.Origins)</ref>

== The existence of transitional forms ==

== Identification problem ==

In ‘’The Origin of Species’’ [[Charles Darwin]] wrote that the fossil record (as it was known then) was lacking in transitional forms.  He predicted, however, that transitional forms would be found.  In accordance with that prediction, since the publication of ‘’The Origin of Species’’ many transitional forms, both fossil and living, have been identified.

A major problem with identifying transitional forms is in determining whether a particular fossil or living thing is truly intermediate between two others, or is merely an unrelated form which has characteristics common to both other forms.

The following are some examples of  known transitional forms<ref>The examples are taken from New Scientist magazine of 1 March 2008, ''What Missing Link?'' by Donald Prothero, professor of geology at Occidental College in Los Angeles and lecturer in geobiology at the California Institute of Technology in Pasadena.</ref>.

[[Archaeopteryx]], for example, has some features in common with both living [[bird]]s and [[reptile]]s, and is often quoted as an intermediate form.

It was not covered with part-[[scale]]s/part-[[feather]]s, but had fully-functioning feathers and [[wing]]s, and was capable of [[flight]].

There is therefore no reason to think that it is not simply a bird with some features in common with reptiles.

=== Fishbians ===

Rather than simply producing the occasional form which appears to be intermediate between two different forms, evolutionists need to demonstrate what [[Charles Darwin]] called a "finely-graduated organic chain".<ref name="chain" />

The so-called “fishbian” sequence of fossils shows the steps by which fish crawled out of the water and onto the land during the [[Devonian]] period.  Fossils exist that span the entire transitionfrom the distinctly fish-like ''Eusthenopteron'' to the four-legged amphibian ''Hynerpeton''. The fossil record of the fish-to-amphibian transition is now among the best documented of all.

Despite many more fossils being discovered since Darwin's time, the continued lack of a series of fossils showing a smooth transition led [[Stephen Jay Gould]] and [[Niles Eldredge]] to propose [[Punctuated Equilibrium]], which says that the change from one form to another took place is short bursts which generally would not leave a fossil trace.

Evolutionists continue to claim that such intermediate forms exist or existed, but have failed to adequately demonstrate any such smooth sequence, as opposed to the occasional form with features common to two other forms.

=== Rhinos ===

== Claims of transitional forms ==

The fossil record of rhinoceroses is extensive. Starting with dog-sized creatures, such as the early [[Eocene]] ''Hyrachyus'', that are barely distinguishable from early tapirs and horses, fossil rhinos gradually diversified into a wide variety of forms. Some of these forms became gigantic, culminating in the huge indricotheres, which were about 7 metres tall at the shoulder and weighed 20 tonnes.  None of the early rhinos had horns. The living rhino family began in the middle [[Eocene]] with primitive creatures such as ''Teletaceras'' which looked much like the earlier “running rhino” type excepting for the development of a chisel-like upper tusk and pointed lower tusk.

In ''The Origin of Species'' [[Charles Darwin]] wrote that the fossil record (as it was known then) was lacking in transitional forms.<ref name="chain">"Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and gravest objection which can be urged against my theory. The explanation lies, as I believe, in the extreme imperfection of the geological record".  Darwin, Charles, ''The Origin of Species'', chapter X.</ref>

He predicted, however, that transitional forms would be found.

Nevertheless, 120 years later, David Raup said that the situation had not improved.<ref>"Well, we are now about 120 years after Darwin, and the 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. The record of evolution is still surprisingly jerky, and ironically, we have fewer examples of evolutionary transitions than we had in Darwin's time. By this I mean that some of the classic cases of Darwinian change in the fossil record, such as the evolution of the horse in North America, have had to be discarded or modified as a result of more detailed information.", Raup, David, "Conflicts between Darwin and paleontology", ''Field Museum of Natural History Bulletin'' 50(1), January 1979, p.25.</ref>

The pinnipeds are seals, sea lions and walruses and are descended from primitive bears.  A recently discovered fossil has provided a beautiful transitional form between the two groups<ref> The early [[Miocene]] fossil ''Enaliarctos''. See ''Science'' vol. 244, page 60.</ref>.  Although superficially like a seal the fossil lacked most of the specialisations that modern pinnipeds require for their aquatic lifestyle.  In addition, its “flippers” had long toes and claws, halfway between bear paw and pinniped flipper.  There was subsequently a great “radiation” of seals and sea lions in the middle and late [[Miocene]], all of which appear in the fossil record.

However, the accompanying "family tree" showing a mere eight fossils in this sequence does not show ''any'' of them as being intermediate to any others, but all being on separate branches.

Furthermore, it has many of the forms in the sequence living contemporaneously with others in the supposed sequence, including some "later" ones living ''earlier'' then their supposed ancestors!

There are many other examples of transitional forms including: velvet worms, lancelets, synapsids, ceratopsians, giraffes, ichthyosaurs and manatees.

== Claims of a lack of transitional forms ==

== Creationist claims of a lack of transitional forms ==

Creationists claim that there there are no transitional forms between the various [[baraminology|created kinds]].

 

Even leading evolutionists have admitted that transitional forms do not exist as expected:

Whilst there is general agreement among evolutionary scientists that many transitional forms exist, by selectively quoting, some creationists seek to demonstrate that evolutionary scientists admit to a lack of transitional forms.  The following quotations have been employed to that end by creationists:

The late paleontologist [[Stephen Jay Gould]] said in 1977:

The late paleontologist [[Stephen Jay Gould]] said in 1977:

== References ==

== References ==

[[Category:Origins Debate]]

[[Category:Origins Debate]]