BIOL 215 Lecture Notes - Lecture 7: Choanocyte, Precambrian, Collagen
25 Jan 2018
School
Department
Course
Professor
Document Summary
Explosion: how did so many body plans arise and why have so few, if any, arisen since the early. Cambrian: adaptive radiation, too specialized upon appearance in the fossil record to have originated in the. Causes: geological conditions, rising oxygen levels, predator-prey relationships. They probably arose but didn"t really diversify until the cambrian. Of 1. 2 billion (fossils -500 million) years of animal evolution, modern humans have been on the planet only 200,000 years. If you take the pax-6 gene of human: insert it during development and overexpress it: you can get an eye to grow on the wing of that fly. Developmental regulatory gene: highly conserved in expression/function across all multicellular animals (sponges - humans) If we all share these, how is it that we look so different: basis of field of evo-devo Developmental change and evolution: gene regulation has emerged as a central mechanism explaining developmental and evolutionary change.
