BIOL 2400 Study Guide - Final Guide: Background Extinction Rate, British Rail Class 33, Generalist And Specialist Species
Document Summary
First law: sustained use of any organ will gradually strength and enlarge that organ. Second law: nature has caused individuals to acquire or lose as a result of the influence of environmental conditions to which their race has been exposed. Unit 1: class 3: from the beginning to the origin. No extinction, no common ancestry, organisms increase up the scale of complexity. New species formed at bottom of scale by spontaneous generation. Coordinated additions of developmental stages in a species. New additions caused certain organs to be used or disused, triggering lamarckian mechanism of change. Discontinuous variation was much more important than continuous variation. New species formed all at once, no intermediates, no gradual change. Internal force pushes species along evolutionary trajectories. Natural selection is important only in producing minor within-species change. Species are related by descent, but natural selection was agreed as the dominant mechanism. Remaining challenges to darwinism were mutationism, orthogenesis and saltationism.