Back in November of 2014, a headline in the Washington Post proclaimed, “Newly discovered fossil could prove a problem for creationists.”[i] The article claims that many creationists have said that the gap between ichthyosaurs, which are aquatic, extinct, dolphin-like reptiles, and land reptiles is so large, it poses a problem for evolution. “Now the gap has been filled,” the article states. What filled in the gap? A creature known as Cartorhynchus (the name Cartorhynchus is not actually mentioned in the Washington Post article, but that is the name of the genus they were talking about). The article claims that “[i]ntense analysis put it smack dab in the middle of the ichthyosaur family. But unlike previously discovered fossils in the lineage, this one wasn’t perfectly suited to life in the ocean.” In fact, the article describes Cartorhynchus as amphibious.
The Washington Post article was not the only one to pick up on this marvelous news. Another article, at Sci-News.com, announced the discovery of the same creature with the headline “First Amphibious Ichthyosaur Found – Cartorhynchus lenticarpus.”[ii] The Sci-News article said that the discovery of Cartorhynchus “is the first to link the dolphin-like ichthyosaur to its terrestrial ancestors, filling a gap in the fossil record.”
The academic article that announced the discovery of Cartorhynchus was published in the journal Nature.[iii] This article reveals that the two news reports exaggerated or implied more than was warranted. For one thing, Cartorhynchus is not an ichthyosaur. Rather, it was identified as an ichthyosauriform. The difference between these two is subtle, but important. Ichthyosauria, or its more generic term, ichthyosaur, is the group that includes the dolphin-like marine reptiles, such as Ichthyosaurus, Ophthalmosaurus, and Shonisaurus. Ichthyosauriformes, or its more generic term, ichthyosauriform, is the group that includes Ichthyosauria and its closest relatives. There is also a larger group, Ichthyosauromorpha that includes Ichthyosauriformes and their closest relatives. Think of it as a nested group, with Ichthyosauromorpha as the largest group, Ichthyosauriformes as a smaller group within Ichthyosauromorpha, and Ichthyosauria as a smaller group within Ichthyosauriformes. It is necessary to explain all of this because Cartorhynchus is classified as an ichthyosauriform, not an ichthyosaur. Thus, it is technically inaccurate to call it the “[f]irst amphibious ichthyosaur.” Moreover, the authors of the article in Nature created Ichthyosauriformes and then classified Cartorhynchus as an ichthyosauriform. In other words, the group Ichthyosauriformes was created to include Cartorhynchus and ichthyosaurs. So much for Cartorhynchus landing “smack dab in the middle of the ichthyosaur family.”
Granted, both the Washington Post article and the Sci-News article may have been referring to ichthyosauriforms when they used the word “ichthyosaur.” However, without clarification, it gives the impression that Cartorhynchus is an ichthyosaur that has one fin in the water and one fin on land.
Speaking of being partway on land and partway on water, the authors of the Nature article made a couple of interesting comparisons. The flipper is described as seal-like, but when two other features, cartilaginous wrists and heavy ribs, are reconciled with an amphibious lifestyle, Cartorhynchus is compared to other creatures. The cartilaginous wrists are compared to juvenile sea turtles and the heavy ribs to dugongs. Note that juvenile sea turtles are only terrestrial as they move from their nest to the sea. Dugongs, for their part, rarely come on land, as they are only occasionally known to give birth on beaches. Both dugongs and sea turtles, while technically amphibious, rarely venture onto land. Typically, “amphibious” conjures up images of seals or otters, happily clambering up on land and diving back into the ocean on a whim. Now, the flipper of Cartorhynchus is compared to that of a seal, but other features are compared to creatures that are barely amphibious, so perhaps it didn’t climb up on land as freely as some of the news articles suggest.
In summary, both articles are technically wrong when it comes to the classification of Cartorhynchus, though they could have just been using a broader meaning of the term “ichthyosaur” for simplicity’s sake. Both articles are technically right that Cartorhynchus may have been amphibious, but without explaining the meaning of the word “amphibious,” it leaves an impression of its habits that are a little skewed. Thus, Cartorhynchus, a unique, primarily aquatic, ichthyosaur-like creature is transformed in the popular media into an amphibious, seal-like, transitional ichthyosaur. It is quite possible that the authors of the articles were not seeking to deceive their readers. Rather, they were simplifying a topic. Nevertheless, their simplifications lead to slightly erroneous conclusions and reveal a bias. We must be careful when reading announcements of new discoveries in case we or others are misled in a similar fashion.
Having said all of that, what about the argument that Carthorhynchus “fills the gap” between ichthyosaurs and terrestrial reptiles? The authors of the article in Nature certainly make that claim. Indeed, Cartorhynchus does share some features with ichthyosaurs, such as flippers with a relatively inflexible joint between the humerus and radius and ulna, and other features with terrestrial reptiles, such as a shorter snout and wider head. Thus, in some ways, Cartorhynchus does indeed fall in between ichthyosaurs and terrestrial reptiles in its anatomy.
It is worth noting that Cartorhynchus is also unique in some of its own ways. For instance, its mouth appears to have been designed for suction feeding, a feature that is rather rare in marine reptiles and unknown in ichthyosaurs.[iv] Nevertheless, it still has a mixture of features. How can, or should, creationists approach Cartorhynchus and explain it in a non-evolutionary way?
Quick on the heels of the Washington Post article, ICR published a brief article by Frank Sherwin questioning the status of Cartorhynchus as a missing link.[v] One of Sherwin’s primary points was that “[e]volutionists should be cautious. The last ‘missing link’ between ichthyosaurs and terrestrial creatures was discovered in 1982 and called Utatsusaurus, but left paleontologist Michael Benton unconvinced. Instead of a missing link, he labeled Utatsusaurus an ichthyosaur because it shows ‘typical ichthyosaurian characters.’”
There is a good point here. Evolutionists should be cautious about being dogmatic that Cartorhynchus fills the gap between ichthyosaurs and terrestrial reptiles. After all, one of the hallmarks of science is that any idea is susceptible to being overturned. Because hypotheses are created using inductive reasoning, all science is capable of doing is eliminating false hypotheses. It is impossible for science to demonstrate that a hypothesis is true, thus every hypothesis is open to being falsified at some point.
Having noted that every idea in science is susceptible to falsification, it should be noted that scientists assume that a lot of things are true. If something has become established in science, it is regarded as true, even though it technically has not been proven true. It just would not make sense for scientists to regard every idea, especially one that has been verified numerous times, as equally suspect. However, new ideas are more suspect as they have been verified less frequently.
In the case of Cartorhynchus, has there been any new information to overturn the idea that it is a transitional form? In 2016, another marine reptile, Sclerocormus, was described.[vi] Sclerocormus was classified as an ichthyosauriform alongside Cartorhynchus, further establishing the latter as a basal form ancestral to ichthyosaurs.[vii] In short, it does not appear that there is mounting evidence that Cartorhynchus does not fill the gap between terrestrial reptiles and ichthyosaurs. Thus, Sherwin’s caution that evolutionists might find Cartorhynchus to not be a transitional form has not yet born out.
Furthermore, Sherwin’s example of Utatsusaurus as a supposed transitional form that has been rejected by some evolutionists is a poor one. True, Michael Benton stated that Utatsusaurus was an ichthyosaur. However, he also said that it was a “basal form” that had “[p]rimitive features, hinting at the land-living ancestry of ichthyosaurs.”[viii] By calling Utatsusaurus an ichthyosaur, Benton was clearly not intending that it was “just an ordinary ichthyosaur.” Rather, he described it as a primitive ichthyosaur that is a transitional form leading to more advanced ichthyosaurs.
As another reason for evolutionists to be cautious, Sherwin claims that “cladists… maintain, ‘Cartorhynchus is actually the first representative of a whole new clade… of ichthyosaur-like pachyleurosaurs,’” and that cladists have “big problems” with the position of the Nature article.
I find this critique to be seriously in error for two reasons. First of all, the article in Nature used cladistics to argue for Cartorhynchus as a transitional form between terrestrial reptiles and ichthyosaurs. In other words, there is no separate group of evolutionists called “cladists” who disagree with the article in Nature: those who wrote the article are cladists themselves. Second, and most disturbing, is that Sherwin’s quote from a cladist comes from the “The Pterosaur Heresies,” a blog run by David Peters.[ix] David Peters is infamous among paleontologists for his questionable techniques.[x] He uses a method called “Digital Graphic Segregation” to analyze photographs of fossils to find bones and other traces that other paleontologists have not identified. Note that the discoveries he makes are not discoveries on the slab of rock that contains the fossil, rather they are “discoveries” made by a program on a digital photograph of the slab of rock. Moreover, the features he “finds” are almost never repeatable by any other paleontologist. Since his ideas have been rejected by paleontologists, Peters has established himself as an authority unto himself, regarding his technique as valid and every other paleontologist as “out to get him.” In short, he is a rogue evolutionist and hardly one that should be used as an example of a typical “cladist.”
As a further note about David Peters, he actually runs two websites: The Pterosaur Heresies, mentioned above, and Reptile Evolution.com.[xi] The latter website is particularly prominent and can show up quite frequently when simple searches are made of extinct reptiles. Both websites should be avoided as they do not represent the views of any anyone aside from Peters himself and, due to his questionable techniques, are fraught with errors. I mention this because not only was one of David Peters’s websites cited by Sherwin in his article, I believe that the istiodactylids on display at the Ark Encounter are based on a reconstruction made by Peters.[xii] I strongly urge my fellow creationists to avoid anything related to David Peters lest we become targeted with guilt by association. If other evolutionists do not regard Peters as a reputable authority, then we could inadvertently bring down criticism on ourselves if we treat Peters as a reliable source.
Sherwin closes his article with the following phrase: “could it be that this new fossil [Cartorhynchus] has no genetic connection with ichthyosaurs, but instead is just another newly discovered extinct reptile?” That is the rub, is it not? While Sherwin’s prior arguments may have incorporated a poor example and cited a rogue evolutionist, his last statement really does hit the nail on the head. What is the difference between Cartorhynchus belonging to a kind and Cartorhynchus as a transitional form between terrestrial reptiles and ichthyosaurs? Genetics. If the former is true, then Cartorhynchus would be genetically distinct from other reptiles. Such a distinction could be demonstrated with cross-breeding experiments. If the latter is true, then Cartorhynchus would share a genetic heritage with other reptiles. Such a relationship could be verified by cross-breeding Cartorhynchus with its immediate ancestor and with its immediate descendent. Note that in both cases, the test is impossible as Cartorhynchus is extinct and cannot interbreed with anything.
When it comes down to it, the best thing creationists can say about Cartorhynchus is that calling it a transitional form requires cross-breeding tests that we cannot perform. This is a double-edged sword because we also can not verify that Cartorhynchus belonged to a separate kind. Rather than putting effort into “proving” that Cartorhynchus “may not” be a transitional form, and inadvertently using a poor example and citing a rogue evolutionist, just explain what Cartorhynchus would be like in the creationist model. My faith in creationism does not rest in scientific proof. Rather, my faith is based on the Word of God. As the Apostle Paul said, “let God by true though every one were a liar” (Romans 3:4). The only proof I need to know that Cartorhynchus is not a transitional form is that God said that he made creatures according to their kinds. Let every scientist be a liar, but I will stick to what God said.
Does Cartorhynchus pose a problem for creationists? Not at all, because our worldview is different from that of an evolutionist. Rather than spending time “proving” that it is not a transitional form, I want to know what Cartorhynchus is like in the creationist model. Doing so might not discredit the evolutionary worldview, but it does bolster the creationist model by demonstrating that it can account for all of the observations that we make about fossils, and the whole world, for that matter.
[i] Rachel Feltman (2014) “Newly discovered fossil could prove a problem for creationists” The Washington Post, retrieved from https://www.washingtonpost.com/news/speaking-of-science/wp/2014/11/05/newly-discovered-fossil-could-prove-a-problem-for-creationists/ on April 27, 2018
[ii] News Staff (2014) “First Amphibious Ichthyosaur Found – Cartorhynchus lenticarpus” Sci-News retrieved from http://www.sci-news.com/paleontology/science-amphibious-ichthyosaur-cartorhynchus-lenticarpus-02257.html on May 10, 2018
[iii] Ryosuke Montani, Da-Yong Jiang, Guan-Bao Chen, Andrea Tinton, Olivier Rieppel, Cheng Ji, and Jian-Dong Huang (2015) “A basal ichthyosauriform with a short snout from the Lower Triassic of China” Nature 517: 485-488
[iv] Ryosuke Motani, Cheng Ji, Taketeru Tomita, Neil Kelley, Erin Maxwell, Da-yong Jiang, Paul Martin Sander (2013) “absence of Suction Feeding Ichthyosaurs and its Implication for Triassic Mesopelagic Paleoecology” PLoS ONE 8(12): e66075
[vi] Da-Yong Jiang, Ryosuke Montani, Jian-Dong Huang, Andrea Tintori, Yuan-Chao Hu, Olivier Rieppel, Nicholas C. Fraser, Cheng Ji, Neil P. Kelley, Wan-Lu, and Rong Zhang (2016) “A large aberrant stem ichthyosauriform indicating early rise and demise of ichthyosauromorphs in the wake of the end-Permian extinction” Scientific Reports 6: 26232
[vii] Note: I am speaking as an evolutionist here. As a creationist, I obviously do not think that Cartorhynchus or Sclerocormus are transitional fossils. They are, however, structurally intermediate and no further studies have shown that they are more like ichthyosaurs than previously thought.
[viii] Michael Benton (2005) Vertebrate Paleontology, 3rd Edition, Blackwell Publishing, Oxford, UK, pg. 152
[ix] David Peters (2014) “Cartorhynchus: An ichthyosaur-mimic, not a basal ichthyosaur” The Pterosaur Heresies, retrieved from https://pterosaurheresies.wordpress.com/2014/11/07/cartorhynchus-an-ichthyosaur-mimic-not-a-basal-ichthyosaur/ retrieved on May 12, 2018
[x] Darren Naish (2012) “Why the World has to ignore ReptileEvolution.com” Scientific American, retrieved from https://blogs.scientificamerican.com/tetrapod-zoology/world-must-ignore-reptileevolution-com/ on May 12, 2018
[xii] The associated sign at the Ark Encounter says that their reconstruction was based on specimen SMNK PAL 1136. A search of this specimen leads to http://reptileevolution.com/SMNSPAL1136.htm, which features a reconstruction of a pterosaur very similar to that shown in the Ark Encounter. Website retrieved on May 12, 2018.