In a post by Dale Drinnon, I was glad to see specific details in critical reports of apparent pterosaurs (Frontiers of Zoology, March 3, 2011, post), but I was a little surprised at how he emphasized an idea about how a modern pterosaur should not appear. In "Ropens, Pterosaurian Sightings And Manta Rays," Drinnon said, "There is a problem in all of these sightings . . . in that the body conformation is NOT what you would expect of a giant Pterosaur." I suggest that insistence on strict conformity with his precise expections are unreasonable. (See the Ropens site on a giant pterosaur.)
Don't confuse two sources of knowledge. The limited knowledge we have of pterosaurs from fossils is not at all the same knowledge that we have from eyewitness reports of modern pterosaurs. If he were more precise, he might say something like this: "Fossils of Rhamphorhynchoid pterosaurs are small, in general, compared with fossils of Pterodactyloid pterosaurs." Of course. Who would disagree with that? But Drinnon has come up with an idea that if pterosaurs were still living, we would expect them to be either non-giants or non-Rhamphorhynchoids, not giant Rhamphoryhynchoids, and that sightings must conform to our expectations. He does not tell us how he arrived at that conclusion, only that "you would not expect" eyewitness reports to be as they are. (See a site about "extinction" and pterosaur fossils)
A serious problem becomes obvious when we consider what he has done with that idea. He uses it to cast doubt on all eyewitness reports that involve a large or giant long-tailed pterosaur or apparent pterosaur. But what would happen to science if all observations were judged by what we had previously expected, and all data involving the unexpected were immediately dismissed? That might appear to be potentially good news for college students at the poverty level, for science textbooks would never again need to be revised, for all scientific knowledge would be declared completed, with no new discoveries allowed.
Modern pterosaurs need not be precisely like what we have so far discovered in fossils. Many species may have lived without leaving any fossils. Many more may have left fossils that we have not yet discovered. Why should those species be exactly like those that have left fossils that we have already discovered? I see no reason for Dale Drinnon to be so dogmatic about what a modern pterosaur might be like.
Don't confuse two sources of knowledge. The limited knowledge we have of pterosaurs from fossils is not at all the same knowledge that we have from eyewitness reports of modern pterosaurs. If he were more precise, he might say something like this: "Fossils of Rhamphorhynchoid pterosaurs are small, in general, compared with fossils of Pterodactyloid pterosaurs." Of course. Who would disagree with that? But Drinnon has come up with an idea that if pterosaurs were still living, we would expect them to be either non-giants or non-Rhamphorhynchoids, not giant Rhamphoryhynchoids, and that sightings must conform to our expectations. He does not tell us how he arrived at that conclusion, only that "you would not expect" eyewitness reports to be as they are. (See a site about "extinction" and pterosaur fossils)
A serious problem becomes obvious when we consider what he has done with that idea. He uses it to cast doubt on all eyewitness reports that involve a large or giant long-tailed pterosaur or apparent pterosaur. But what would happen to science if all observations were judged by what we had previously expected, and all data involving the unexpected were immediately dismissed? That might appear to be potentially good news for college students at the poverty level, for science textbooks would never again need to be revised, for all scientific knowledge would be declared completed, with no new discoveries allowed.
Modern pterosaurs need not be precisely like what we have so far discovered in fossils. Many species may have lived without leaving any fossils. Many more may have left fossils that we have not yet discovered. Why should those species be exactly like those that have left fossils that we have already discovered? I see no reason for Dale Drinnon to be so dogmatic about what a modern pterosaur might be like.
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