1. New Knowledge Changes How We Classify Classification systems change with expanding knowledge about new and well-known organisms.

2. Early skeleton sheds light on primate evolution Published: Tuesday, May 19, 2009

3. NEW YORK (AP) — The nearly complete skeleton of a small 47 million- year-old creature found in Germany was displayed Tuesday by scientists who said it would help illuminate the early evolution of monkeys, apes and humans. About the size of a small cat, the animal has four legs and a long tail. It's not a direct ancestor of monkeys and humans, but it provides a good indication of what such an ancestor may have looked like, researchers said at a news conference. Because the skeleton is so remarkably complete, scientists believe it will provide a window into primate evolution. The animal was a juvenile female that scientists believe died at about 9 or 10 months. "She tells so many stories. We have just started the research on this fabulous specimen," said Jorn Hurum, of the University of Oslo Natural History Museum, one of the scientists reporting the find. The creature is nicknamed Ida after Hurum's 6-year-old daughter. The unveiling, at New York's Museum of Natural History, was promoted by a press release for the cable TV show History, which called it a "revolutionary scientific find that will change everything." Mayor Michael Bloomberg, among the speakers at the news conference, called it an "astonishing breakthrough.“

6. Problems: Organisms that move alike may not be related Organisms that don’t move alike may be related Some organisms go in no categories Some organisms go in several categories Scientist Aristotle Observed appearance behavior movement Classified fly Swim crawl-walk -run 4 B.C.

7. 1750’s Scientist Carolus Linneaus Observed Structural descriptions Classified Observable features “Oak with deeply divided leaves...”

8. Today’s Classification Scientist Us Observed Theoretically share common ancestor Classified Similar evolutionary history

10. Tomorrow Scientist You in college Observed Diversity of organisms and the way they relate to each other Classified Phylogenetic Cladistics/ Systematics

11. Examples of Current Classification: Fossil Record- Comparative Homologies Embryonic Development Cladograms DNA sequencing Taxonomic Diagrams Molecular Clocks

12. Systematics … is the study of the evolution of biological diversity, and combines data from the following areas. Fossil record

13. Comparative homologies

14. Embryonic Development Which column is the human? #1 #2 #3 #4 #5 #6 #7 #8 Pig? Tortoise? Cow? Rabbit? Human? Salamander? Chicken? Rabbit?

16. Cladograms Although cladistics provides us with the best current method of determining evolutionary relationships, it is not perfect. Contradictions among advanced features often suggest alternative evolutionary trees. In such cases, the cladogram consistent with the most features is chosen for the time being. True evolutionary relationships can never be definitively established, either by examining fossils or studying DNA. But we can get closer and closer to the actual sequence of evolution by testing hypotheses about relationships with as many features as possible. Why use cladistics? Although cladistics provides us with the best current method of determining evolutionary relationships, it is not perfect. Contradictions among advanced features often suggest alternative evolutionary trees. In such cases, the cladogram consistent with the most features is chosen for the time being. True evolutionary relationships can never be definitively established, either by examining fossils or studying DNA. But we can get closer and closer to the actual sequence of evolution by testing hypotheses about relationships with as many features as possible.

17. Comparative sequencing of DNA/RNA among organisms

18. Taxonomic Diagrams MammalsTurtlesLizards and Snakes CrocodilesBirdsMammalsTurtlesLizards and Snakes CrocodilesBirds CladogramPhylogenetic Tree BioEd Online

19. Molecular clocks Molecular clocks allow scientists to use the amount of genetic divergence between organisms to extrapolate backwards to estimate dates.