To what are fins homologous? Explain the importance of a sturdy ribcage in tetrapods. Spell. Write. Once we have researched all the fossils relevant to the water-to-land transition, we begin to get an idea of what timeframe this transition happened in. By Shorey Andrews . 15. The Ribcage . Created by. Humerus (Limbs) 11. Kenichthys is a genus of sarcopterygian fish from the Devonian period, and a member of the clade tetrapodomorpha. We know the lobe-finned fish are from 390-380 million year old rocks. amells44. 12. 13. consist of a spool-like centrum, which connects in front and back with other centra. Digits. 9. What do we mean in biology when we use the term homology? 14. Why is a sturdy ribcage important for tetrapods? Why do many of the transitional fossils between fish and tetrapods have flat heads? Having the head and the shoulders separate would become a very important feature of the first exclusively land-based tetrapods. Tetrapods evolved from a group of animals known as the Tetrapodomorpha which, in turn, evolved from ancient Sarcopterygii (lobe-finned fishes) around 390 million years ago in the middle Devonian period; their forms were transitional between lobe-finned fishes and the four-limbed tetrapods. Lungs would have also required the development of a sturdy ribcage, a hallmark of four-limbed animals (also known as tetrapods). (Origin of tetrapods Click and learn – choose three points are say what changed and why it was needed). Transition to Land. PLAY. Later tetrapods evolved necks with seven or more vertebrae, some long and some short, permitting even more mobility. Flashcards. 10.Feet in tetrapods 11.Explain the importance of a sturdy ribcage in tetrapods. Tetrapod, (superclass Tetrapoda), a superclass of animals that includes all limbed vertebrates (backboned animals) constituting the classes Amphibia (amphibians), Reptilia (reptiles), Aves (birds), Mammalia (mammals), and their direct ancestors that emerged roughly 397 million years ago during the Scientific theories are powerful because they allow us to make predictions about our world. 13. Terms in this set (52) Compared to the densisty of water, what is the density of a vertebrates body- ... What did tetrapods loose inorder to have a … What is homology? 11. Vert 2. What is homology? Tiktaalik is also the first known animal to have evolved a neck. 18. To what are fins homologous? 13. Tetrapods, which are four-limbed vertebrates ('tetra' means 'four'), evolved from those lobe-finned fishes and over time made their way onto land. What evolutionary advancements needed to evolve for vertebrates to adapt to land? Learn. Why did this adaptation evolve?