BLG 144 Lecture Notes - Lecture 1: Natural Selection, Special Creation, Cestoda
Document Summary
Theory of special creation: all species are independent, earth is young, only 6000 years old, species are unchanging. Plato - species are created by god and are unchanging (fixed) Typological thinking species are unchanging and variation is misleading. Great chain of being ladder shows fixed orgs by their increased size and complexity (humans top) Evolution species change over time b/c traits vary + only certain alleles are. Population thinking variations among individual is key to understand the nature of species. The theory of evolution by natural selection is revolutionary b/c 1. Overturns species being static: replaced typological thinking with pop thinking, scientific with mechanism. Descent with modification descendant species (different) came from ancestral species. Theory of evolution by natural selection: species change through time, + related by common ancestor, evidence for change through time: Geologic time scale based on rock formation. Many layers through radioisotopes conclusion = life on earth is ancient.
