Keep in mind no one has witnessed the entire history of life of earth 2. no one has observed the process of speciation from start to finish Evolutionary biology is a historical science Look at the end products of events Other historical sciences: geology, archaeology

Evolution as a historical science Q: If no one has observed the entire process, how can we determine if evolution has/is occurring? A: Deduction. If evolution has been going on for 3.5 billion years on earth, then we can make predictions about the patterns that we should observe Evolution is a theory and if the predicted patterns are not found, then we reject evolution as a theory

Evidence for Evolution artificial selection Plants Dogs 2. evolution in nature Many pest are resistant to various compounds used to control them - e.g. herbicide, antibiotics b. Industrial melanism -- Peppered moth

Fossil Record Provides a record of species that lived long ago Age Appearance of 3.5 bya bacteria 600 mya invertebrates 440 mya fishes 225 mya mammals 1.5 mya "man"

Fossils simplest fossils found in oldest layers (3.5 b.y.a), More complex forms are found in younger layers fossils in younger layers are more similar to living organisms than are fossils in older layers gradual changes are seen in many fossil lineages (e.g. horses) and intermediate forms have often been found

Fossils Transitional Fossils – fossils that contain features of several species Derived trait – new traits not in ancestral species Ancestral traits – primitive features in ancestral species Archaeoptyerx

Homologous Structures Similar features that originated in a common ancestor Develop from same embryonic structure Have similar structure but different functions

Analogous Structures Serve identical functions and look somewhat alike BUT, very different in embryologic development Moth Bat Pterodactyl Bird

Vestigial Structures Features that were used but no longer serve a function Organism with vestigial feature share common ancestry with an organism that has a functional version of the same feature

Whale Snake

Similarities in Embryology Early embryos of many different vertebrate species look similar Similarities in early development are a indication of common ancestry

Similarities in Macromolecules The more similar the proteins are in different species the more closely related the species are The greater the similarity, the more recently the organisms are considered to have diverged from a common ancestor

What is a Cladogram? A branching diagram showing evolutionary relationships among species based on similarities and differences in physical and/or genetic characteristics

Cladogram/Phylogenetic Tree

Uses of Phylogenetic Trees Organize knowledge of biological diversity Structure classifications Providing insight into events that occurred during evolution

Number of differences from human cytochrome c Create a cladogram using the following information Species Number of differences from human cytochrome c Monkey 1 Rabbit 4 Horse 6 Chicken 7 Frog 8 Turtle Tuna 9 Shark 14

Create a cladogram using the following information. Organism Derived Characteristic Vertebrate Bony Skeleton Four Limbs Amniotic Egg Egg with shell Hair Shark present Absent Fish Present Amphibian Crocodile Bird Rabbit

1. The image illustrates what evolutionary concept?

2. Which of the following is NOT a component of the Theory of Evolution by Natural Selection? A. competition for food and space B. variation among species C. inheritance of acquired characteristics D. survival and reproduction 3. A structure that seems to serve no purpose in an organism is called: A. homologous B. vestigial C. dichotomous D. fossilized

4. In science, theories are: A. an educated guess B. a known fact C 4. In science, theories are: A. an educated guess B. a known fact C. absolute and unchangeable D. the best explanation for a set of data or observations 5. Larmarke is to "Inheritance of Acquired Characteristics" as Darwin is to _____ A. divergence of related species B. homologous structures C. evolution by natural selection D. speciation by common descent

Any variation that can help an organism survive in its environment is called a(n): A. adaptation B. characteristic C. competition D. vestigial structure The strongest evidence for change over a long period of time comes from: A. DNA B. fossils C. embryo studies D. direct observation of living species

8. The dog breeds we have today were developed through: A 8. The dog breeds we have today were developed through: A. natural selection B. artificial selection (selective breeding) C. sexual selection D. acquired selection 9. The finches on the Galapagos island were similar in form except for variations of their beaks. Darwin observed that these variations were useful for: A. attracting a mate B. defending territory C. building nests D. gathering food