Biological Evolution concerns changes in living things during

Biological Evolution • concerns changes in living things during the history of life on Earth. • Explains that living things share common ancestors. • Over time, biological processes such as natural selection give rise to new species. Darwin called this process "descent with modification"

Biological Evolution • Natural selection: Environment impacts who lives to produce offspring • Survival of the fittest: Lion King

Evidence Supporting Biological Evolution The fossil record Age of the Earth Homologous or Common Structures Distribution of Species Similarities during development (embryos) DNA and Molecular Evidence

Evolution Descent with modification A long path leads from the origins of primitive "life, " which existed at least 3. 5 billion years ago. This path is best understood as a product of evolution.

Eye Evolution

Evolution’s Key “Small change over unimaginable blocks of time” -Darwin

The Fossil Record The fossil record thus provides consistent evidence of systematic change through time of descent with modification.

The Fossil Record The fossil record clearly shows that change followed change on Earth. So critters also had to change along with the Earth, or go extinct.

The Missing Link Many pieces of the fossil record are missing…why? It is unusual for organisms to fossilize It is difficult to find and preserve those fossils that do exist most organisms die and leave no trace.

Life Form Millions of Years Since First Known Appearance (Approximate) Microbial (procaryotic cells) 3, 500 Complex (eucaryotic cells) 2, 000 First multicellular animals Shell-bearing animals Vertebrates (simple fishes) Amphibians Reptiles Mammals Nonhuman primates Earliest apes Australopithecine ancestors of humans Modern humans 670 540 490 350 310 200 60 25 4 0. 15 (150, 000 years)

Age of the Earth 4. 5 billion years

Centuries of Earth’s layers

Homologous Structures

Con’t Structures Look at differences and similarities among the skeletons Homologous structures - parts of different organisms, often quite different, that developed from the same ancestral body parts.

Homologous structures

Other Structures Vestigial organs - structure that serves no useful purpose or function in an organism. Why do organs become vestigial? Mutation Why would those changes be passed on? Didn’t harm the organism

The Distribution of Species Life on the separate Continents Evolved differently Australian animal life is very different

Galapagos Finches

The Distribution of Species

Similarities During Development Embryology

Similarities During Development what does this mean? Early stages of development are repeated

Whales evolved from a land mammal

DNA and Molecular Biology Evidence

DNA and Molecular Biology Evidence ATP is the energy carrier found in ALL living organisms

DNA and Molecular Biology Evidence ALL LIVING ORGANISMS USE DNA AND/OR RNA THE DNA BASE SEQUENCES ARE VERY SIMILAR FOR SIMILAR SPEICES

DNA and Molecular Biology Evidence A wide variety of complicated proteins (like cytochrome C) are shared by many organisms. ALL living things are carbon based.

Creationism and the Evidence for Evolution

Is life a tree with a common ancestor for the trunk?

Evolution: Online Lessons for Students: Activity 2 - Evidence for Evolution Web. Quest Evidence Supporting Biological Evolution | Science and Creationism: A View from the National Academy of Sciences, Second Edition

Essay Exam http: //www. pbs. org/wgbh/evolution/index. html

Areas of Interest on the Site Darwin Change Extinction Survival Sex Humans Religion Student Lesson/Online Lessons (Use Quicktime for Videos)

Evolution: Survival: Microbe Clock

Darwin Observed Nature

Darwin’s Premises • Individuals vary • Organisms produce more offspring than will survive • Population remains fairly constant • Environment is constantly changing

Darwin Concluded • Competition: only some survive • Most fit traits survive & reproduce • The genetic variation that increases fitness will eventually appear in the whole population

Hardy Weinberg • No change in the gene pool if……

Hardy Weinberg • Mating is random • Mutations do not occur • No immigration or emigration • Large population or allele frequency is high • Natural selection is not operating