Presentation on theme: "Scientific Evidence of Common Ancestry"— Presentation transcript:
1Scientific Evidence of Common Ancestry Reporting Category 3Biological Evolution and ClassificationStation 10Scientific Evidence ofCommon Ancestry
2Essential Question – Bell Ringer What information can be gained by examining the fossil remains of the ancestors of modern organisms?By studying fossil remains, scientists can determine how closely related fossil organisms are to modern species. Fossil remains also give scientists insight into what environmental conditions were like where the fossil organisms lived.
3Pre-Review QuestionInformation about past life, including the structure of organisms, what they ate, what ate them, their environment, and the order in which they lived can be determined using….A. VestigiologyB. The fossil recordC. StratologyD. Ecology
4Pre-Review QuestionWhat does this diagram represent?Fossil Record
5Pre-Review QuestionBased on DNA sequencing, which organisms are more closely related?A. AAC GCA TTA GCCB. GAC GCA TTA GCAC. AAC AAT CCA GCAA and B
6Pre Review QuestionWhy did you choose A and B as your answer to the previous question?Because they have the fewest DNA sequence differences.What type of homology does this represent? A. Molecular B. Anatomical C. DevelopmentalA. Molecular
7Pre-Review QuestionThese two cladograms represent the same information. Based on the graphic, which two organisms are most closely related?
8Lab ActivitiesYou will now go to the lab and complete the activities for today’s topics.
9Draw this chart in your journal and fill in the name of the organism and the DNA sequencing from the lab activity.
11Examine this diagram to answer the following questions in your journal.
12How has the anatomy of the horse changed over time? Skull? Legs? All parts of the horse’s anatomy have become larger.The face is longer, and the cheek teeth have changed in number and size (longer and less sharp).The lower legs and feet havechanged, and the number of toes has been reduced from four smaller toes to onelarge toe that we now call the hoof.
13More SpecificallyThe number of toes these horses have decreases in number:The oldest fossil has four toes; oligohippus has three; mercyhippus also has three but two are not fully formed; pliohippus has one toe but remnants of two additional ones near the knee. The modern horse, equus, has only one toe, which has evolved into a hoof while the toes have decreased in number, the skulls have increased in size.
14I need to remember…….. I need to remember . . . DNA sequences are used to determine how closely related organisms are to one another.Examining fossil remains enables scientists to understand how modern organisms developed over time.
15Post Review Question Vestigial structures Analogous structures What do thesestructuresrepresent?Vestigial structuresAnalogous structuresHomologous structuresRadiant structures
16Post Review QuestionIf two different species have homologous structures, what does this tell you about their evolutionary history?They share a common ancestor.They do not share a common ancestor
17Post Review QuestionThe process by which unrelated organisms independently evolve similarities when adapting to similar environments.A. Convergent EvolutionB. Divergent EvolutionC. Adaptive RadiationD. Symbiosis17
18Post Review Question What does the circled structure represent? Vestigial structureAnalogous structureHomologous structureRadiant structure