Evolutionary Transitions

noun A type of lobe-finned fish that includes the ancestors of land vertebrates

• The crossopterygian fish is known for its unique lobe fins.
• Have you ever heard of a crossopterygian fish? It's pretty cool.
• That crossopterygian fish is one funky-looking creature.
• Her ideas were like crossopterygian fossils, ancient yet still relevant.

noun a group of primitive amphibians that lived during the Carboniferous and Permian periods

• Adelospondyli is an extinct group of amphibians that lived during the Carboniferous period.
• I just learned about adelospondyli in my biology class.
• Those adelospondyli creatures look like something out of a sci-fi movie.
• The complexity of the adelospondyli fossil record is a puzzle waiting to be solved.