Mechanisms of Change Selection Types of Evolution Macroevolution
- Slides: 18
Mechanisms of Change: Selection
Types of Evolution Macroevolution change of one kind of organism into another “macro” = large this has not been observed, but is assumed in the current evolutionary theory
Types of Evolution – cont’d Microevolution small changes in organisms through selection “micro” = small has been observed is assumed in current evolutionary theory to accumulate until a large change is seen
Discuss Explain the difference between macro- and micro- evolution
Selection Example to be used: A colony of clams lives at a particular beach. These clams come in three varieties – white, grey, and black. Grey is, of course, an intermediate color between the two extremes, white and black. These clams are a part of a sea-bird’s natural diet – however, they are unable to see the clams well which blend into the background of the sand rock underneath. The beach contains areas of light, dark and intermediate sand in various amounts.
Natural Selection – organisms which have the best-suited traits survive in their environment
Natural Selection – cont’d Natural Selection – organisms which have the bestsuited traits survive Four types: directional selection one extreme of a trait is best and is selected
Natural Selection – cont’d Natural Selection – organisms which have the bestsuited traits survive Four types: disruptive selection multiple extremes of a trait are best and are selected
Natural Selection – cont’d Natural Selection – organisms which have the bestsuited traits survive Four types: stabilizing selection intermediate/average form of trait is selected
Natural Selection – cont’d Natural Selection – organisms which have the bestsuited traits survive I made these Four types: just for YOU! La la laaaaaa!!!!!! sexual selection presence of a trait influences mating trait can be physical OR behavioral
Darwin’s 5 points 1. 2. 3. 4. 5. Population has variations. Some variations are favorable. More offspring are produced than survive Those that survive have favorable traits. A population will change over time.
La. Marck’s Theory Jean Baptiste La. Marck: 1800’s Believed: Change Occurs Over Time inheritance of acquired characteristics acquired changes were passed to offspring Law of Use and Disuse If a body part were used, it got stronger If body part NOT used, it deteriorated Examples: Body builders or pierced ears
Discuss Name and describe the four types of natural selection. Give an example of each type of selection [NOT my example – pick another]
Artificial Selection – humans select desirable traits and breed out non-desirable traits crop farming
Artificial Selection – cont’d Artificial Selection – humans select desirable traits and breed out non-desirable traits animal breeding
Discuss What is the difference between natural and artificial selection?
Selection – cont’d Selection works on POPULATIONS not on individuals we do not select the best corn plant just to plant one seed and make one plant!! just so, one animal with new characteristics must cause change to the entire population for it to make a difference
Homework Complete the Darwin’s Five points worksheet title of worksheet = “Natural Selection”
- Macroevolution 7 patterns
- Macroevolution definition
- Microevolution
- Hybrid fertility
- Difference between prezygotic and postzygotic barriers
- Macroevolution definition
- Section 17-4 patterns of evolution answer key
- Macroevolution
- Types of natural selection in evolution
- Evolution types
- What are the mechanisms of evolution
- Mechanisms evolution
- Mechanisms of evolution
- Mechanisms of evolution
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- Mechanisms of evolution
- Mechanisms of evolution graphic organizer
- Chapter 15 section 3 shaping evolutionary theory answer key
- Natural selection vs evolution