Evidence to Support Evolution ACADEMIC ninth grade science
Warm up… 1. Use the diagram to describe the steps of natural selection for the mouse.
Pace of Evolution GRADUALISM: Slow Even pace PUNCTUATED EQUILIBRIUM: Quick bursts Many periods of no change
Examples: Sickle cell Anemia Peppered Moth
Evidence to Support Evolution
1. Fossils Any trace of a dead organism Calcium in bones is replaced with harder elements Soft tissues don’t often fossilize Age determined by radiometric dating
2. Comparative Embryology Vertebrates have similar early stages; gill slits, “fins”, a tail Differences accumulate as development continues New instructions are added to old instructions inherited from ancestors.
2. Comparative Embryology
3. Transitional Forms Intermediates between old and new species Ex: modern horse descended from dog-sized animal with multiple toes
Transitional Forms Fish to Amphibians
Transitional Forms Reptiles to Birds
Transitional Forms Land Mammals to Aquatic Mammals
4. Homologous Structures Structures with a common ancestry Modified versions of structures from other organisms Ex: bones in appendages
4. Homologous Structures
5. Vestigial Structures Structures with no present function Remnants of the past; Previously served a function Ex: human appendix-may once have been used for digestion Ex: whale’s pelvis-not needed for swimming, is needed for walking
5. Vestigial Structures
NOW… SciChat
Warm up… 1. With your SciChat partner, complete sections 1 & 2 of the Evidence for Evolution Exploration
Warm up… 1. With your SciChat partner, complete sections 3 & 4 of the Evidence for Evolution Exploration
Warm up… TAKE OUT YOUR REVIEW PART A What are the steps to natural selection? How does the peppered moth show these steps?
6. DNA and Proteins DNA make an organism’s proteins DNA sequence holds the evolutionary history If species changes, their DNA changes Closely related organisms share more similar DNA Ex: humans and chimps share 98% DNA
6. DNA and Proteins Human-Human=99.5% similar Human-Chimpanzee=98% similar Human-Cat=90% similar Human-Cow=80% similar Human-Mouse=75% similar (90% analogous regions) Human-Chicken=60% similar Human-Fruit Fly=60% similar
Now… SciChat Presentations
Now… Rainfall and Bird Beaks Gizmo
Which is NOT homologous & Why? A Human Lizard Octopus B Bird Whale Grasshopper Lizard Human
So…evolution can cause speciation Speciation: formation of a new species as a result of natural selection
Madagascar & Speciation
Now… Read about Antibiotic Resistant Bacteria. Answer the questions on the back of the Natural Selection Examples Sheet
Warm up… 1. Use the diagram and explain the process of speciation.
Antibiotic Resistance
Now… Find your new group Complete Speciation Work time
Warm up… Did any individual Peppered moth change its color during its lifetime? Why? (or why not?) Explain the change from light colored to dark colored moths. 36:15
Now… Quick Check-15 minutes-you know it or you don’t Peppered Moth Graph This MUST be finished TODAY Graded TODAY and returned for the questions TOMORROW Work time
Warm up… What is the difference between an independent variable and a dependent variable? Explain the steps of Natural Selection. How does antibiotic resistance show natural selection?
Check yours… X Transitional Vestigial DNA Fossils Embryology Homologous Transitional Vestigial Embryology DNA Fossils Gill Slits… X Forelimbs… DNA… Archaeopteryx… Whale pelvis… Common ancestor… Modern horse…
Check yours… 2. UNDERLINE each of these terms or ideas (not the descriptions) Overproduction Inherited variation Struggle to survive Successful reproduction Adaptation of the species
Check yours… 3. CIRCLE your example Underline each piece of natural selection you used to defend it
Warm up… Read the article on your sheet and begin to answer the questions on the back.
Fossil Activity
Warm up… A Make FOUR observations (facts) about these fossil footprints. Consider size, shape, & position. Make FOUR inferences (educated guesses) about the prints that reconstruct the events that may have caused this pattern. There is more than one possible answer. B C
Warm up… Take out the sheet from Friday Complete the chart and questions with your partner, using the packet on the table
Transitional Forms Activity Turn to pages 112-113 in the GREEN textbook. Read about the transitional forms of the whale. In your notes, describe what scientists think the ancient ancestor the modern whale was like.
DNA and Proteins Activity Cytochrome C article???????