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NATURAL SELECTION

NATURAL SELECTION. There are 2 variations of the beetles, green and red. The birds prefer eating the green beetles. Over generations the red beetles increase in population because they are not eaten by the birds. More survive to produce more offspring. Generations later….

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NATURAL SELECTION

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  1. NATURAL SELECTION

  2. There are 2 variations of the beetles, green and red. The birds prefer eating the green beetles. Over generations the red beetles increase in population because they are not eaten by the birds. More survive to produce more offspring. Generations later…. Over time the red beetles have been selected over the green beetles So what happens to the birds now?

  3. Natural Selection Simulation mutation • http://phet.colorado.edu/en/simulation/natural-selection • Why are there different colors? • Why do wolves eat white rabbit (in the equator environment)? • Why do # brown rabbits increase over time? 4) What is it called when the # brown rabbits increases over time? 5) What if the environment changed to the arctic? Brown are camouflaged or move faster Brown survive, reproduce & their babies are brown Evolution The white rabbits would survive better and the # white bunnies would increase

  4. Why do giraffes have long necks?

  5. Who was Charles Darwin? • British scientist that in 1859 published The Origin of Species • Stated that all life today came from a common ancestor • Change from one to many is called evolution • This happens by a process called natural selection. • http://www.youtube.com/watch?v=nMgLF8n4DnA

  6. Darwin Galapagos Voyage of H.M.S. Beagle, 1831 - 1836 • 90 feet of ship, 74 people living together for 5 years...

  7. PHYSICAL: This moth mimics an owl’s eyes BEHAVIORAL: This monkey is using tools to get food CHEMICAL: this orchid smells like a female bee

  8. INCORRECT MODEL OF EVOLUTION: BASED ON NEED

  9. Why does this not work? Change through use and disuse

  10. Natural Selection’s Explanation Ancestors had different neck lengths Through natural selection, longer necks survived and passed on their genes. Eventually all giraffes had long necks.

  11. 225 Million Years Ago the continents were together making a super continent called Pangaea • The continents split and populations were separated. • This increased the variety of living things because they were in new environments,which would select for specific adaptations and isolated these species from reproducing with original form.

  12. EFFECTS OF ISOLATION

  13. ONE Ancestor Many Varieties • What are the different types? • What could cause all the variety? http://www.youtube.com/watch?v=sCEeefdaRcw

  14. Common Ancestor- We did not come from monkeys, we just share a common ancestor

  15. Adaptation • the evolutionary process where a population becomes better suited to its environment. • This process takes many generations. • A feature which is especially important for an organism's survival. • For example, the adaptation of horses' teeth to the grinding of grass • Flat teeth (due to genetic mutation) chew grass better

  16. How does Evolution Work? • Natural Selection- survival of the fittest • Organisms best suited to their environment • Natural selection is the result of four features of living systems: • 1) variation – differences in the population because of genetic mutation • 2) inheritance - parents pass on their genetic mutations to their offspring • 3) selection - some organisms reproduce more (fittest) than others • 4) time – happens over time, takes many generations

  17. Evolution • the change in the inherited traits (passed on from parents to offspring) of a populationover many generations. • These traits could be: • physical (teeth shape) • chemical (ability to use sun for energy) • behavioral (run fast). • This change is caused by mutations in the genes. • http://www.youtube.com/watch?v=yVqJ_mQazik

  18. Theories on Life • Theory of Evolution • Science • Based on evidence • Creationism • Religion • Based on faith

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