No Transitional Fossils?

Published on Tuesday, December 8, 2009 By Drew Stedman

I was recently presented with a challenge from my former Christian high school biology teacher who is a young earth creationist:

“I still don’t know about the “thousands of transitional species” that you referred to in the fossil record. I will look forward to you pointing those out to me.”

This was a challenge I was more than happy to accept as the evidence from the fossil record unequivocally supports evolution. In response to this list, which took some time to put together, I received a power point presentation of Bible verses about creation. I thought this was ironic because I had just finished rereading the book of Genesis. It was also very telling, because it so clearly shows that in order to believe in creationism, one must completely ignore evidence and rely entirely on blind faith in scripture. Evidence as we shall see, is the enemy of Creationism. Which is why Creationists do not accept evidence.


I hope those of you who are interested in this topic will find this resource useful when being confronted with the statement “There are no transitional fossils”


For the purpose of clarity, I will define transitional fossils as: The fossilized remains of intermediary forms of life that illustrate an evolutionary transition (Wikipedia).


I must emphasize that transitional fossils are those that exhibit a transitional feature. “The transition itself can only be illustrated and corroborated by transitional fossils, but it will never demonstrate an exact half-way point between clearly divergent forms.” (Wikipedia) Because of our understanding of geology and the specific conditions required for the formation of a fossil, we would not expect to have a perfect, or “complete” fossil record. However, upon careful examination of the record, the evidence of a clear and branching pattern of divergence can be observed in the transitional features of taxa. This evidence becomes increasingly overwhelming the more one studies the fossil record as is seen throughout many of the scientific papers referenced in the list below.


Before reviewing this list I find it important to note that ALL of these examples appear in the fossil record in the correct strata and periods predicted by the evolutionary tree of life. This is most extremely exhibited in the case of Tiktaalik. Tiktaalik was discovered because of these predictions, which led Neil Shubin and his colleagues to Ellesmere Island in Nunavut, Canada where they found the fossil in the precise layer of rock they expected to.


Also, the trees of life constructed from the fossil record are identical to those independently constructed from genetics, anatomy, embryology, molecular biology etc. This adds serious weight to the validity of the fossil record.


In this list I have included references for each example in relevant peer-reviewed scientific papers along with a link to each article (or article listing) when possible, as well as relevant news articles. I have also included a link to the Wikipedia entry for each example. This is a very streamlined list of transitional fossils which doesn’t include the much more recent ancestry of humans. We will get to that soon.


Note: (Some of the preliminary information I used to compile this list came from online posts by DonExodus, a biologist whose education includes: BS Evolutionary Biology- UNC-Charlotte. Doctoral- UNC. I used some information from his videos, Transitional Fossils I and II: http://www.youtube.com/view_play_list?p=F9729F67CD4034C9) I did my own research in finding more information and peer-reviewed papers about each example. As part of this I spoke with Kevin de Queiroz, Research Zoologist at the Department of Vertebrate Zoology Division of Amphibians & Reptiles at the Smithsonian National Museum of Natural History who provided me with information on the transitional taxa and stem reptiles which mark the transition between amphibians and reptiles in the fossil record. A site that he directed me to is helpful and relevant to this entire list:


tolweb.org


TRANSITIONAL FOSSILS


The following two articles are relevant to the information found in this list.


Heterochronical patterns of evolution in the transitional stages of vertebrate classes.

Schad W.

Acta Biotheor. 1993 Dec;41(4):383-9.

http://www.ncbi.nlm.nih.gov/pubmed/8191805?ordinalpos=6&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Extreme convergence in the body plans of an early suchian (Archosauria) and ornithomimid dinosaurs (Theropoda).

Nesbitt SJ, Norell MA.

Proc Biol Sci. 2006 May 7;273(1590):1045-8.

http://www.ncbi.nlm.nih.gov/pubmed/16600879?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=2&log$=relatedarticles&logdbfrom=pubmed


FISH TO AMPHIBIANS


Eusthenopteron – an example of the beginning of the formation of characteristics only found in tetrapods: Internal nostrils, Labyrinthodont teeth, two part cranium, Intracranial joint, the development of arm and leg bones (humerus, ulna, radius, femur etc.)

http://en.wikipedia.org/wiki/Eusthenopteron


Related paper:

Terrestrial-style feeding in a very early aquatic tetrapod is supported by evidence from experimental analysis of suture morphology.

Markey MJ, Marshall CR.

Proc Natl Acad Sci U S A. 2007 Apr 24;104(17):7134-8. Epub 2007 Apr 16.

http://www.ncbi.nlm.nih.gov/pubmed/17438285?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Panderichthys – development of large tetrapod head, pelvic girdle to support developing limbs, a breathing tube on the top of head.

http://en.wikipedia.org/wiki/Panderichthys


Related paper:

The pelvic fin and girdle of Panderichthys and the origin of tetrapod locomotion.

Boisvert CA.

Nature. 2005 Dec 22;438(7071):1145-7.

http://www.ncbi.nlm.nih.gov/pubmed/16372007?ordinalpos=5&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Gogonasus – “the most complete, acid-prepared Devonian tetrapodomorph fish yet discovered.” “shares several features with that of Tiktaalik”

http://en.wikipedia.org/wiki/Gogonasus


Related paper:

An exceptional Devonian fish from Australia sheds light on tetrapod origins.

Long JA, Young GC, Holland T, Senden TJ, Fitzgerald EM.

Nature. 2006 Nov 9;444(7116):199-202. Epub 2006 Oct 18

http://www.ncbi.nlm.nih.gov/pubmed/17051154?ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Tiktaalik – Well-preserved fossils were found in 2004 on Ellesmere Island in Nunavut, Canada. (Wikipedia). Had fish scales, fish gills, tetrapod rib bones, mobile neck and lungs. Fins with basic wrist bones and fingers that were weight bearing. These are clearly traits that are in development.

http://en.wikipedia.org/wiki/Tiktaalik


Related papers:

The cranial endoskeleton of Tiktaalik roseae.

Downs JP, Daeschler EB, Jenkins FA Jr, Shubin NH.

Nature. 2008 Oct 16;455(7215):925-9.

http://www.ncbi.nlm.nih.gov/pubmed/18923515?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb.

Shubin NH, Daeschler EB, Jenkins FA Jr.

Nature. 2006 Apr 6;440(7085):747-9.

http://www.ncbi.nlm.nih.gov/pubmed/16598250?ordinalpos=7&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Ichthyostega – New bones in pelvic girldle (pubis, ischia, ilia), Rib cage and sternum, still had fish lateral line system, gills and finned tail.

http://en.wikipedia.org/wiki/Ichthyostega


Related paper:

Contrasting developmental trajectories in the earliest known tetrapod forelimbs.

Callier V, Clack JA, Ahlberg PE.

Science. 2009 Apr 17;324(5925):364-7.

http://www.ncbi.nlm.nih.gov/pubmed/19372425?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Temnospondyli – Eryops and Cacops, Branchiosaurus

http://en.wikipedia.org/wiki/Temnospondyls

http://en.wikipedia.org/wiki/Eryops

http://en.wikipedia.org/wiki/Cacops

http://en.wikipedia.org/wiki/Branchiosaurus


Related paper:

The armoured dissorophid Cacops from the Early Permian of Oklahoma and the exploitation of the terrestrial realm by amphibians.

Reisz RR, Schoch RR, Anderson JS.

Naturwissenschaften. 2009 Jul;96(7):789-96. Epub 2009 Apr 4.

http://www.ncbi.nlm.nih.gov/pubmed/19347261?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Others:

Anthracosauria – Ancestral line to reptiles. Ex. Diadectes

http://en.wikipedia.org/wiki/Anthracosaur

http://en.wikipedia.org/wiki/Diadectes


Cheirolepis, Osteolepis, Ichthyostega, Pholidogaster, Pteroplax.

http://en.wikipedia.org/wiki/Cheirolepis

http://en.wikipedia.org/wiki/Osteolepis

http://en.wikipedia.org/wiki/Ichthyostega

http://en.wikipedia.org/wiki/Pholidogaster

http://en.wikipedia.org/wiki/Pteroplax


AMPHIBIANS TO REPTILES


For information about the transition between amphibians to reptiles I consulted Kevin de Queiroz – Research Zoologist Department of Vertebrate Zoology Division of Amphibians & Reptiles Smithsonian National Museum of Natural History. He directed me to Seymouria as well as several other stem reptiles that can be found on tolweb.org.


Seymouria – Labyrinthodont skull and teeth with reptilian vertebrae, pelvis, humerus and digits; amphibian ankle. (See first article)

http://en.wikipedia.org/wiki/Seymouria


Related papers:

Early tetrapod relationships revisited.

Ruta M, Coates MI, Quicke DL.

Biol Rev Camb Philos Soc. 2003 May;78(2):251-345.

http://www.ncbi.nlm.nih.gov/pubmed/12803423?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


FIRST DESCRIPTION OF SKULL OF LOWER PERMIAN SEYMOURIA SANJUANENSIS (SEYMOURIAMORPHA: SEYMOURIIDAE) AT AN EARLY JUVENILE GROWTH STAGE

Jozef Klembara, David S. Berman, Amy C. Henrici, Andrej Čerňanský, Ralf Werneburg, and Thomas Martens

Annals of Carnegie Museum 76(1):53-72. 2007

http://www.bioone.org/doi/abs/10.2992/0097-4463(2007)76%5B53:FDOSOL%5D2.0.CO%3B2


Hylonomus and Limnoscelis – slightly amphibian skull with reptilian skeleton.

http://en.wikipedia.org/wiki/Hylonomus

http://en.wikipedia.org/wiki/Limnoscelis


Related papers:

Discussion on ecology of earliest reptiles inferred from basal Pennsylvanian trackways

David G. Keighley, John H. Carder, Adrian F. Park, Ronald K. Pickerill, John W.F. Waldron, Howard J. Falcon-Lang and Mike J. Benton

Journal, Vol. 164, 2007,1113-1118

http://jgs.geoscienceworld.org/cgi/content/extract/165/5/983


Microsaurs and the Origin of Captorhinomorph Reptiles

Joseph T. Gregory Dept. of Paleontology, University of California Berkeley

American Zoologist 1965 5(2):277-286; doi:10.1093/icb/5.2.277

http://icb.oxfordjournals.org/cgi/content/abstract/5/2/277


REPTILES TO MAMMALS


Pelycosaur Synapsids – ex. Ophiacodon, Varanopidae, Ophiacodontidae. Intermediate between cotylosaurs and therapsids.

http://en.wikipedia.org/wiki/Ophiacodon

http://en.wikipedia.org/wiki/Varanopidae

http://en.wikipedia.org/wiki/Ophiacodontidae


Related papers:

Fossil Synapsids: The Ecology and Biology of Mammal-like Reptiles.

Kemp TS.

Science. 1987 May 15;236(4803):862-863

http://www.ncbi.nlm.nih.gov/pubmed/17777853?ordinalpos=18&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


The mammary gland and its origin during synapsid evolution.

Oftedal OT.

J Mammary Gland Biol Neoplasia. 2002 Jul;7(3):225-52.

http://www.ncbi.nlm.nih.gov/pubmed/12751889?ordinalpos=10&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Therapsids – ex. Dimetrodon – Many therapsid fossils show gradual intermediate changes from reptilian to mammalian features: Ribs become restricted to chest instead of entire body, legs are not spread out but pulled in.

http://en.wikipedia.org/wiki/Therapsids

http://en.wikipedia.org/wiki/Dimetrodon


Related papers:

Evolution of bone microanatomy of the tetrapod tibia and its use in palaeobiological inference.

Kriloff A, Germain D, Canoville A, Vincent P, Sache M, Laurin M.

J Evol Biol. 2008 May;21(3):807-26. Epub 2008 Feb 25.

http://www.ncbi.nlm.nih.gov/pubmed/18312321?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Post-Jurassic mammal-like reptile from the Palaeocene.

Fox RC, Youzwyshyn GP, Krause DW.

Nature. 1992 Jul 16;358(6383):233-5.

http://www.ncbi.nlm.nih.gov/pubmed/1630490?ordinalpos=16&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Cynodont theriodonts – ex. Cynognathus – Very mammal-like reptiles. Differentiated teeth, differentiated vertebral column, mammalian limbs and digits, has undeniably reptilian jaw joint.

http://en.wikipedia.org/wiki/Theriodont

http://en.wikipedia.org/wiki/Cynognathus


Related papers:

[Acquisition of masticatory structures in mammalian reptiles (preliminary study]

Buyle-Bodin Y, Dubreuil D.

J Biol Buccale. 1976 Jun;4(2):91-108.

http://www.ncbi.nlm.nih.gov/sites/entrez


Cynodont reptile with incipient mammalian jaw articulation.

Romer AS.

Science. 1969 Nov 14;166(907):881-2.

http://www.ncbi.nlm.nih.gov/pubmed/5345204?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=2&log$=relatedarticles&logdbfrom=pubmed


[Jaws of primitive mammals]

Tsubamoto T.

Clin Calcium. 2005 Jun;15(6):1045-8.

http://www.ncbi.nlm.nih.gov/pubmed/15930721?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=3&log$=relatedarticles&logdbfrom=pubmed


Tritylodont theriodonts – ex. Tritylodon – even more mammal characteristics but still has reptilian jaw joint.

http://en.wikipedia.org/wiki/Tritylodon


Related paper:

THE POSTCRANIAL SKELETON OF THE LATE TRITYLODONT BIENOTHEROIDES

Ailin Sun and Yuhe Li

Vertebrata PalAsiatica Volume XXIII, No.2 April, 1985 pp. 135-150

http://www.paleoglot.org/files/Sun&Li_85.pdf


Examples of transition b/w reptilian inner ear and jaw to mammalian inner ear and jaw:


Ictidosaur theriodonts – ex. Pachygenelus (formerly known as Diarthrognathus) – has all mammalian features of tritilodonts and has double jaw joint, both the reptilian jaw joint and the mammalian jaw joint side by side in the skull.

http://en.wikipedia.org/wiki/Ictidosaur

http://en.wikipedia.org/wiki/Pachygenelus


Related papers:

An Ictidosaur Fossil from North America.

Chatterjee S.

Science. 1983 Jun 10;220(4602):1151-1153

http://www.ncbi.nlm.nih.gov/sites/entrez


The dentitions of the Tritheledontidae (therapsida: cynodontia)

Gow CE.

Proc R Soc Lond B Biol Sci. 1980 Jul 17;208(1173):461-81.

http://www.ncbi.nlm.nih.gov/sites/entrez


Morganucodonts – ex. Morganucodon – Same double jaw joint but with the MAMMALIAN JOINT DOMINANT with reptilian joint moving inward

http://en.wikipedia.org/wiki/Morganucodonta

http://en.wikipedia.org/wiki/Morganucodon


Related paper:

Mammal Teeth from the Forest Marble (Middle Jurassic) of Oxfordshire, England.

Freeman EF.

Science. 1976 Dec 3;194(4269):1053-1055.

http://www.ncbi.nlm.nih.gov/sites/entrez


Eupantotheres – ex. Amphiperatherium – Mammals begin to show complex molar cusp patterns. Has mammalian jaw joint.


Related papers:

Crystallite orientation discontinuities and the evolution of mammalian enamel–or, when is a prism?

Lester KS, von Koenigswald W.

Scanning Microsc. 1989 Jun;3(2):645-62; discussion 663

http://www.ncbi.nlm.nih.gov/pubmed/2683049?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Mammal Teeth from the Forest Marble (Middle Jurassic) of Oxfordshire, England.

Freeman EF.

Science. 1976 Dec 3;194(4269):1053-1055.

http://www.ncbi.nlm.nih.gov/pubmed/17840306?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


An example of the transition between egg-laying reptiles and placental mammals is the Platypus which is warm-blooded, has fur, produces milk but lays eggs instead of having live young. Some parts of their skeleton are more similar to a reptile than to a mammal. EX. Obdurodon – Extinct platypus that had molar teeth.

http://en.wikipedia.org/wiki/Obdurodon


Related article:

Platypus Genome Reveals Secrets of Mammal Evolution

Scott Norris for National Geographic News May 7, 2008

http://news.nationalgeographic.com/news/2008/05/080507-platypus.html


Related paper:

New information about the skull and dentary of the Miocene platypus Obdurodon dicksoni, and a discussion of ornithorhynchid relationships.

Musser AM, Archer M.

Philos Trans R Soc Lond B Biol Sci. 1998 Jul 29;353(1372):1063-79.

http://www.ncbi.nlm.nih.gov/pubmed/9720105?ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


REPTILES TO BIRDS


Anchiornis huxleyi – New feathered Dinosaur just discovered in China in the past few weeks. Has “dino fuzz” and four limbs with wing-like characteristics which also found in later specimens such as Arhaeopteryx.

http://en.wikipedia.org/wiki/Anchiornis


Related article:

http://www.sciencenews.org/view/generic/id/47800/title/Feather-covered_dinosaur_fossils_founds


Archaeopteryx – has many avian characteristics such as feathers but also some that are only found in reptiles such as: has no bill, trunk region vertebra are not fused as in all birds, pubic shafts with slightly angled cross-section, neck attaches to skull from rear as in dinosaurs not from below like birds. Claws on 3 non-fused digits a feature that no adult bird has. The sacrum occupies 6 vertebra (birds always have 11-23) along with many other traits.

http://en.wikipedia.org/wiki/Archaeopteryx


Related paper:

A well-preserved Archaeopteryx specimen with theropod features.

Mayr G, Pohl B, Peters DS.

Science. 2005 Dec 2;310(5753):1483-6.

http://www.ncbi.nlm.nih.gov/pubmed/16322455?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=1&log$=relatedarticles&logdbfrom=pubmed


More on Archaeopteryx:


From Answers in Genesis:

“One of the biggest dilemmas for those who want to believe that dinosaurs evolved into birds is that the so-called feathered dinosaurs found thus far are dated to be about 20 million years more recent than Archaeopteryx. This is a problem for evolution because Archaeopteryx is now generally recognized to be a true bird.”


I must note that this argument, while it has been thoroughly refuted is further weakened by the very recent discovery of Anchiornis huxleyi, which pre-dates Archaeopteryx. Also, Archaeopteryx is NOT widely recognized as a true bird. It is widely recognized as a transitional form between reptiles and birds, it could in fact be more accurate to describe it as a “true reptile” rather than a true bird because it actually has more reptilian characteristics than avian ones.


An article from UC Berkeley:

http://www.ucmp.berkeley.edu/diapsids/birds/archaeopteryx.html


I have also heard a similar argument that uses this quote from Dr. Alan Fedduccia: “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.”

While Fedduccia believes that Archaeopteryx is fully a bird, he is in the minority in that regard. This is a classic case of quote mining in a weak attempt to overlook that the fossil clearly has both reptilian and avian traits.

Dr. Fedduccia also said of Archaeopteryx:

“…The creature thus memorialized was Archaeopteryx lithographica, and, though indisputably birdlike, it could with equal truth be called reptilian…. The Archaeopteryx fossil is, in fact, the most superb example of a specimen perfectly intermediate between two higher groups of living organisms–what has come to be called a “missing link,” a Rosetta stone of evolution….”


Sinornis santensis – Bird traits: short trunk, claws on toes, stronger flight-feather bones, short hand. Reptilian traits: Reptilian stomach ribs, non-fused hand bones, pelvis, teeth and tail.

http://en.wikipedia.org/wiki/Sinornis_santensis


Related paper:

Early Evolution of Avian Flight and Perching: New Evidence from the Lower Cretaceous of China.

Sereno PC, Chenggang R.

Science. 1992 Feb 14;255(5046):845-848.

http://www.ncbi.nlm.nih.gov/sites/entrez


Las Hoyas Birds – Reptilian pelvis and legs, bird-like shoulder. Transistions between Archaeopteryx and modern birds.


Related paper:

The birds from Las Hoyas.

Sanz JL, Ortega F.

Sci Prog. 2002;85(Pt 2):113-30.

http://www.ncbi.nlm.nih.gov/sites/entrez


An additional note: Chicken bills can be induced to form teeth because they still have dormant genes for making teeth. Why would they have genes for making teeth if not for a toothed ancestor?


Articles about teeth in birds:

http://abcnews.go.com/Technology/story?id=1666805


http://www.scienceblog.com/cms/hens_teeth_not_so_rare_after_all_10081.html


http://www.npr.org/templates/story/story.php?storyId=5230538


LAND MAMMALS to WHALES


Should see transition between ears that are designed to hear on land and those that are designed for the water.


Pakicetus – Distinct whale skull, but with nostrils on tip of snout. Ears which are partially modified for hearing under water.

http://en.wikipedia.org/wiki/Pakicetus


Related paper:

Skeletons of terrestrial cetaceans and the relationship of whales to artiodactyls.

Thewissen JG, Williams EM, Roe LJ, Hussain ST.

Nature. 2001 Sep 20;413(6853):277-81

http://www.ncbi.nlm.nih.gov/pubmed/11565023?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


Ambulocetus natans – A whale with four legs. Stubby front legs with well developed back legs and large feet that stick out like tail flukes.

http://en.wikipedia.org/wiki/Ambulocetus_natans


Related paper:

“Ambulocetus natans, an Eocene cetacean (Mammalia) from Pakistan”

J. G. M. Thewissen, S. I. Madar, and S. T. Hussain

Courier Forschungsinstitut Senckenberg (1996) 191: 1–86.


Related article:

http://www.neoucom.edu/DEPTS/ANAT/Thewissen/whale_origins/whales/Ambulocet.html


Rodhocetus – hind legs which were shorter than A. natans. Could probably waddle on land but with powerful tail. Nostrils moved back from tip of snout.

http://en.wikipedia.org/wiki/Rodhocetus


Related paper:

Origin of whales from early artiodactyls: hands and feet of Eocene Protocetidae from Pakistan.

Gingerich PD, Haq Mu, Zalmout IS, Khan IH, Malkani MS.

Science. 2001 Sep 21;293(5538):2239-42. Epub 2001 Sep 19.

http://www.ncbi.nlm.nih.gov/sites/entrez


Basilosaurus isis – Whale with legs but hind feet had 3 toes and small remnant of 2nd toe.

http://en.wikipedia.org/wiki/Basilosaurus_isis


Related paper:

Hind Limbs of Eocene Basilosaurus: Evidence of Feet in Whales.

Gingerich PD, Smith BH, Simons EL.

Science. 1990 Jul 13;249(4965):154-157.

http://www.ncbi.nlm.nih.gov/sites/entrez


Prozeuglodon – Very tiny hind legs, had vestigal 6 inch legs at rear of 15 foot body. Whale-like skull with dorsal nostrils.

http://paleodb.org/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=53288


Related paper:

Replacement of Deciduous First Premolars and Dental Eruption in Archaeocete Whales

Mark D. Uhen

Journal of Mammalogy 81(1):123-133. 2000 doi: 10.1644/1545-1542(2000)081


<0123:RODFPA>2.0.CO;2


http://www.bioone.org/doi/abs/10.1644/1545-1542%282000%29081%3C0123%3ARODFPA%3E2.0.CO%3B2?journalCode=mamm


These fossils hold extra weight because of the fact that sometimes whales and dolphins are born with intact feet, which sometimes even have toes.


Related papers:

Limbs in whales and limblessness in other vertebrates: mechanisms of evolutionary and developmental transformation and loss.

Bejder L, Hall BK.

Evol Dev. 2002 Nov-Dec;4(6):445-58.

http://www.ncbi.nlm.nih.gov/pubmed/12492145?ordinalpos=4&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


On the development of Cetacean extremities: I. Hind limb rudimentation in the Spotted dolphin (Stenella attenuata).

Sedmera D, Misek I, Klima M.

Eur J Morphol. 1997 Feb;35(1):25-30.

http://www.ncbi.nlm.nih.gov/pubmed/9143876?ordinalpos=6&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum



Discussion

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  2. James Foard says:

    Hi,
    I’m James Foard, the author of The Darwin Papers, free and online at http://www.thedarwinpapers.com. I was considering entering your group, since I have been a little bit disillusioned (this word may be with one “l”, I’m busy, but please don’t play the
    “spell check” game that some evolutionists love to use to skirt the larger issues involved) by some of the various brands of Christianity that I have been involved in, however when I came to see that to a man (and woman) you all embrace the hackneyed, disproven theory of evolution I decided to stay within the bounds of orthodox Christian belief. You actually changed my mind by your rigid and fundamentalist adherance to Darwin’s dogma.
    This is curious, since it is not only Christians who believe that Darwin had it wrong, but many in the Hindu and Moslem world as well. I’m saying this, because you make such a play for evolution, it is so important for all of you in your rejection of your former beliefs, it has become an alternate belief system for you now, and in your article on beliefs and science, where you argue about science and theories not being merely accepted on faith, it is evident that what you really meant by “science” was evolution, after all, nobody really has to have faith that 2+2=4, or that certain chemicals mixed together produce an altogether new compound, or that the laws of celestial mechanics are real; these are demonstratable facts; your really using science as a code word for evolution, as evidenced by your illustration of the dinosaur at the end of your article.
    I read with interest your various “proofs” of transitional fossils, you have really gone to a lot of work to engage in what is popularly known as “elephant hurling”, throwing such a mass of references into the stewpot that it would take somebody a month’s worth of time to investigate every one of them and show them to be the frauds that they are. Even with latin nomenclature used in the different links to Wikipedia and other sources, and the claims that they represent transitional forms, with your lobed fishes and salamanders, the references are all repeating the same mantra, that they evolved because we said they evolved. For evidence of this, I will give you three references from my book (I have nothing to sell, it’s all free, I don’t get any profit from my site):
    http://www.thedarwinpapers.com/oldsite/number6/number6.htm
    http://www.thedarwinpapers.com/oldsite/number6/number6.htm#Hunt
    http://www.thedarwinpapers.com/oldsite/number5/darwin5.htm
    I’m a seeker of truth, and Darwin’s theory is not truth. I became a creationist years before I was a Christian. I was not raised in a Christian home, so had no initial bias against evolution, I was taught it in school as we all were if we went to public schools, and as a teenager I began to investigate eastern religions, and when I read some of the Hindu theories of kalpas and yugas, ages of the universe and the earth, I realised the theory of evolution had, in reality after the curtain has been pulled back from Darwin, the
    Wizard of Evolution, precious little to back it up with fact. It was only after this, and studying Hinduism and Buddhism for years that I realised my need for a Saviour, but even if you’ve decided you don’t want or need Christ (this may not apply to all of you, I just mention this because I don’t want to be accused of proselytizing in relating my story), you can be freed from the confining and superstitious dogma of evolution.
    God bless you,
    James Foard

    • Evolution says:

      Irreducible Complexity has been disproved, by the way, just as other evidence for Darwin’s Theory has been gathered aside from the evidence of his time.

      Hence why the branching of life as found by the fossil record so closely maps the evidence gathered and construed independent of evolution by genetics, molecular biology, anatomy, and embryology, which show the exact same diversity of life that Evolution does.

      Your entire argument is bogus, honestly, since you attack Darwin’s original theory, compared to what we know now, you make the claim that Natural Selection doesn’t lead to new information in the Genome, (which has also been disproved) and then you claim that irreducible complexity (which HAS been reduced, by the way) means evolution can’t exist.

      Do you work for the Discovery Institute?

      Also, if evolution didn’t exist, please, do explain Vestigial Organs.

    • System Administrator says:

      Sir Isaac Newton did not fully understand gravity. Was Newton fraud? Is gravity a myth?

      Darwin was right about common descent. Genome sequencing has proven this beyond any reasonable doubt. (I believe the odds currently stand at at 1 in 10 to the 6,280th power, otherwise.)

      Adherence to Darwin’s Dogma? Dogma doesn’t change. I think most of us here believe in accepting any new discoveries, whether they align with our current world views or not. I think we also understand Darwin’s role in the process of understanding evolution. We certainly don’t hold his words as infallible.

  3. MPWorth says:

    Hello, I’d just like to say that I’m a Christian and I’ve recently become convinced of the fact of human evolution (or at least a common ancestry). I have no problem with full-blown Darwinian natural selection, and I do not feel that this needs to affect my faith in Christ. (A historical Christ with a literal, physical resurrection).

    I was very very angry when I researched church history myself and found out that the opposition to evolution has nothing to with science but rather with a misguided understanding of what Genesis is trying to say, and a misapprehension of what design really is.

    I think the church needs to re-examine its doctrine of Scripture, as well as the philosophy involved in the word “design” in order to make headway on this.

    So, I guess I just wanted to say that there are thinking Christians who are willing to look evolution full in the face. I’m glad there are thinking Christians out there who accept evolution, because otherwise, the blatant intellectual dishonestly of the majority might have caused me to leave the faith.

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