Mechanisms of Evolution
Artifical Selection
Farmers and Breeders
Plants and animals with desirable characterisics to reproduce
Evoultion in the farm stock
People instead of nature select organisms to reproduce
Sources of Genetic variation
Mutations
Is change in DNA
Evoultion is based n the accumlation of many mutations
Gene Flow
Movement of genes from one population to another
Sex
Can intoduce new gene combinations into populations
Natural Selection
Variation in traits
Differential reproduction
Heredity
Continuation for the best adaptest
Biological Evolution
Life on earth shares a common ancestor
Descent with modification
Small-scale:changes in gene frequency from one generation to another
Large-scale:desent of different species from one common ancestor over generations
Evolution is both observable and testable
Fossil record
Study of living species , e.g Darwin's finches
Artifical seletion in laborotary
Genetic mutation
Adaptation
Feature common in populations that provides improved functions
Well fitted to thei function and produced by natural selection
Non-adaptation: Vestigial structures
Evolution is not a ladder of progress
Causes of mutations
DNA fails to copy accurately
External influences. e.g. exposure to specific chemicals or radiation
Religion and science are very different things
In science only natural causes are used to explain natural phenomena
In religion, beleifs are beyond the natural world