Darwin vs Lamarck 2 explanations of evolution one

Lamarck • 1. Tendency towards perfection - all organisms have the urge become better.

Lamarck – con’t • 3. Acquired characteristics- the traits that an organism acquires during

• 1. Overproduction- Each species produces more offspring that can survive to adulthood.

• 3. Genetic Variation- variations or differences occur among members of same species

4. Survival of the fittest /Natural Selection- Organisms with traits that make them well

• 5. As natural selection continues over generation, species change and become better

• Using these theories explain how finches where there are large, hard seeds

Lamarck 1. Finches want bigger beaks. 2. Finches used their beaks a lot and

Darwin 1. Overproduction- too many finches. 2. Competition- not enough food; only large seeds

4. Natural selection- the finches with the large thick beaks could open seeds and

Another example • 1. Overproduction- too many finches • 2. Struggle- food; on the

• 4. Survival of the Fittest- the small beaked finches and large beaked

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Darwin vs. Lamarck 2 explanations of evolution- one right one wrong. Evolution- change in species over time

Lamarck • 1. Tendency towards perfection - all organisms have the urge become better. • 2. Use and Disuse- organsims can alter their traits by use or disuse

Lamarck – con’t • 3. Acquired characteristics- the traits that an organism acquires during lifetime will be passed on to offspring.

What did Darwin say?

• 1. Overproduction- Each species produces more offspring that can survive to adulthood. 2. Competition/Struggle. Because of overproduction, organisms must compete for resources like water, shelter, food, escape predators

• 3. Genetic Variation- variations or differences occur among members of same species

4. Survival of the fittest /Natural Selection- Organisms with traits that make them well adapted to their environment have a better chance of surviving to adulthood to reproduce and therefore passing on their well adapted genes to the next generation.

• 5. As natural selection continues over generation, species change and become better adapted to their environment.

• Using these theories explain how finches where there are large, hard seeds to eat have evolved large thick beaks.

Lamarck 1. Finches want bigger beaks. 2. Finches used their beaks a lot and they got thick. 3. They passed the thick beak trait their acquired on to their offspring.

Darwin 1. Overproduction- too many finches. 2. Competition- not enough food; only large seeds 3. Variation- Finches with small, medium, and large beaks.

4. Natural selection- the finches with the large thick beaks could open seeds and survive to reproduce more than others. 5. After generations the finches with short and medium beaks died out and large beaked finches increased in the population.

Another example • 1. Overproduction- too many finches • 2. Struggle- food; on the Galapagos during droughts there are small seeds and large seeds, but few medium seeds. • 3. Variation- small, medium, and large beaks

• 4. Survival of the Fittest- the small beaked finches and large beaked finches survive more and reproduce more. • 5. Evolution- There is an increase in finches with small and large beaks.