ABSTRACT Most biology textbooks present as fact the idea that ancient fish came out of the water and evolved into amphibians. The most common scenario is that droughts dried up the bodies of water they lived in. Those with stronger fins slithered across the land to other ponds and lakes, acquiring stronger fins with each generation. These fins gradually evolved into legs while all of the other structures of amphibians evolved as well. Such a scenario is contrary to the available evidence. Some of the changes that would have had to happen: • Amphibian spines become segmented and bony. However, fish proposed as ancestors (coelacanths or lungfish) have a flexible notochord that never develops into a segmented spine. • Two types of vertebrae, rhachitomous and lepospondylous, would have had to evolve independently. • Amphibians would have to develop a pelvic girdle. • Fins would have to develop into legs attached to the new pelvic girdle. • Since the body weight would no longer be supported by water, both the bones and muscles would have to become much stronger. • Swim bladders would have to develop into functional lungs. • Eyes would have to change from focusing in water to focusing in air. • Living crossopterygian fish and lungfish reproduce by internal fertilization. Every type of amphibians except the snakelike caecilians reproduces by EXTERNAL fertilization. • All amphibians except newts undergo metamorphosis; coelacanths and lungfish do not. The Lamarckian idea that new structures can be created by use and disuse of body parts (e.g., stronger fins) has been thoroughly falsified. The only way such changes could occur would be by a lengthy series of beneficial mutations. There are six Paleozoic orders of amphibians and three modern ones. The only fish that had an overall shape similar to amphibians were crossopterygians, which were shaped somewhat like ichthyostegids. No proposed common ancestor has the features that would be necessary to give rise to more than one or two of the amphibian orders. Even according to standard geologic dating, the supposed ancestral, transitional, and terminal fossils are in the wrong sequence. KEYWORDS Amphibian evolution THE AUTHOR David Prentice has a B.S. in Physics, an M.Ed. Curriculum & Instruction, and an M.A. Science Teaching. He has a Louisianna lifetime secondary certification in Physics, Chemistry, Biology, General Science, Mathematics. He has taught on creation and apologetics in 13 countries. David Prentice, Kenner, Louisianna prentice@instruction.com © Cedarville University International Conference on Creationism. The views expressed in this publication are those of the author(s) and do not necessarily represent those of Cedarville University. 9th 2023 686 Prentice, D. 2023. Unresolved issues in hypothetical fish-to-amphibian evolution [poster]. In J.H. Whitmore (editor), Proceedings of the Ninth International Conference on Creationism, pp. 686-687. Cedarville, Ohio: Cedarville University International Conference on Creationism. UNRESOLVED ISSUES IN HYPOTHETICAL FISH-TO-AMPHIBIAN EVOLUTION
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