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Natural Selection. Natural Selection. What does the phrase “survival of the fittest” mean to you? Natural Selection- means that nature selects which organisms survive If their adaptations allow them to survive better in the world, then they pass off their genes to their offspring.
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Natural Selection • What does the phrase “survival of the fittest” mean to you? • Natural Selection- means that nature selects which organisms survive • If their adaptations allow them to survive better in the world, then they pass off their genes to their offspring. • If their adaptations do NOT allow them to survive, then they will die.
Example: • A population of birds searches for food among the rocks on a beach. • Some birds have long, pointed beaks. They can easily pick up food from the cracks between the rocks. • Other birds have shorter, round beaks. They cannot reach the food
Example: • The birds with the pointed beaks are more likely to stay alive. • Their babies will have the same kind of beaks. • After several generations, many m ore birds on the beach will have long, pointed beaks.
Natural Selection Simulation • Click Here • For teachers- click on the MICE simulation
Natural Selection Activity • Pass out lab sheet. • Scene: • On a distant planet there exists 5 species of a creature called a Woolybooger. Each Woolybooger is similar except their mouth has variations. All woolyboogers eat beans.
Natural Selection Activity • Some woolyboogers have a clothespin mouth (demonstrate how to use the clothespin to pick up beans) • Some woolyboogers have a tweezer mouth (demonstrate) • Some have a needle mouth (demonstrate).
Activity: • One year a new species of woolybooger was discovered, this woolybooger was called the Spoon-Mouthed Woolybooger (demonstrate). • Each of you will play the part of a woolybooger on this planet. • The spoon-mouth wooly booger is rare, so only two of you will get to be this type of wooly booger.
Trial 1 • You have 1 minute to gather as many beans as you can. • ONLY USE YOUR UTENSIL • After 1 minute, tally the amount of beans you collected and record • If you did not collect 20 beans, your woolybooger has died • If your woolybooger dies, you can be an offspring from the surviving woolyboogers.
Trial 2 • You have 45 seconds to gather as many beans as you can. • After 45 seconds, tally the amount of beans you collected and record • If you did not collect 20 beans, your woolybooger has died • Answer questions on lab sheet • If your woolybooger dies, you can be an offspring from the surviving woolyboogers.
Trial 3 • You have 30 seconds to gather as many beans as you can. • After 30 seconds, tally the amount of beans you collected and record • If you did not collect 20 beans, your woolybooger has died • Answer questions on lab sheet • If your woolybooger dies, you can be an offspring from the surviving woolyboogers
Trial 4 • You have 15 seconds to gather as many beans as you can. • After 15 seconds, tally the amount of beans you collected and record • If you did not collect 20 beans, your woolybooger has died • If your woolybooger dies, you can be an offspring from the surviving woolyboogers. • STOP HERE AND ALLOW STUDENTS TO FINISH QUESTIONS
Final Questions: • 1. What happens to animals that cannot compete as well with other animals in the wild? • 2. Can you think of any real-life examples of the woolybooger, where one species has a definite advantage over another?
Final Questions • 3. If only one species is considered the "fittest", why do we still have so many variations among species. Why do some birds have very long pointy beaks, while other birds have short flat beaks?
