Цена позвоночника – Семихатов, Скучас

A Question of Science. The Price of the Spine. Interview by Alexey Semikhatov and Pavel Skuchas. It is generally accepted that vertebrates represent the pinnacle of animal development. However, this path is not only a chronicle of victories, but also a history of complex evolutionary compromises. The acquisition of a strong internal framework deprived our ancestors of jellyfish regeneration and increased the risk of injury; the development of jaws and teeth simplified digestion but made it energy-consuming; and the emergence onto land granted unprecedented freedom but also condemned them to painful and dangerous childbirth, the loss of the lightness of the aquatic environment, and an eternal struggle with gravity. In this episode of "A Question of Science," we invite you to examine the evolution of vertebrates as a series of specific biological "upgrades" with paleontologist, Doctor of Biological Sciences, and Head of the Department of Vertebrate Zoology at St. Petersburg State University, Pavel Skuchas. 00:00 Topic and Guest 01:11 How Many Vertebrates Are There on Earth? 01:32 Ancient Vertebrates 02:22 What an Early Cambrian Earth Inhabitant Looked Like 03:12 Who Are Vertebrates 04:07 The Cambrian Explosion 04:45 The First Vertebrates 06:33 Why Bone Appeared 08:30 The Appearance of Fish and Jaws 11:15 The Appearance of Teeth 15:13 Descendants of Fish Who Came to Land 19:28 The Appearance of Joints and the Sacrum 20:48 Amniotes 23:15 Ribs and Neck Elongation 26:16 Further Modifications of the Spine 28:17 Spinal Cord 30:54 The Spine and Head Skeleton 32:02 The Spine and Animal Size 33:18 If It Were Not for the Spine 34:09 Bipedalism 35:41 The Main Vulnerability of Vertebrates 36:59 Vertebrates – the Pinnacle of Evolution? #semikhatov #evolution #spine #educational