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What is “Natural Selection”?. Bell Ringer: What are reasons why animals like wooly mammoths and saber tooth tigers aren’t around anymore?. Game Rules. No cheating!! You must get 20 beans to survive If you die, you can only be a new tipple of an existing tipple Stop when you get to 20
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What is “Natural Selection”? Bell Ringer: What are reasons why animals like wooly mammoths and saber tooth tigers aren’t around anymore?
Game Rules • No cheating!! • You must get 20 beans to survive • If you die, you can only be a new tipple of an existing tipple • Stop when you get to 20 • When time is called put your mouth-part down.
Our Tipple Population • What trends do you see?
Discussion • What do you infer happens to real animals that cannot compete as well as others? • Can you think of any real-life examples of the tipple, where one kind of animal has an advantage over another?
Peppered moths • In England, two kinds of peppered moth existed: light and dark. • After the industrial revolution, trees turned dark from soot. Which one do you think camouflaged better? Light or dark?
Natural Selection • Natural Selection is the process through which organisms with better adaptations for their environment live longer, compete better and reproduce more than organisms without those adaptations. • You may have heard this described as “survival of the fittest”
Discussion Continued • Sometimes new species are introduced to an area and they take over. Why do you think this happens?
Natural Selection • Natural Selection is the process through which organisms with better adaptations for their environment live longer, compete better and reproduce more than organisms without those adaptations. • You may have heard this described as “survival of the fittest”
Natural Selection • If only the “fittest” survive, how do we have so many variations among species? For example, how can there be so many kinds of birds in Florida?
Exit Ticket • In the beginning we had only 2 spoon-mouthed tipples, but in the end we had lots. How can natural selection explain this? Write your answer in 1-2 sentences and hand to me at the door.
Natural Selection In your own words, what is natural selection?
Natural Selection • Natural Selection is the process through which organisms with better adaptations for their environment live longer, compete better and reproduce more than organisms without those adaptations.
Natural Selection • There are already variations in the population due to our different traits. • Can you think of a trait that an animal in the arctic would want to have? • What about an animal in the desert?
Natural Selection • Game: http://www.pbs.org/wgbh/nova/evolution/evolution-action.html • What happened to the creatures as the background changes?
Natural Selection • There are already variations in a population • Some of those variations are beneficial for the organism
Natural Selection 3. The remaining organisms reproduce 4. Over many generations of birds eating beetles, the brown beetles are more common.
Natural Selection • http://media.hhmi.org/fittest/natural_selection.html