Theory of Evolution Chapter 13
Charles Darwin 1831 sent as a naturalist on the HMS Beagle to survey the South American coast Studied animals and plants encountered on the journey He was struck by the fact that the plants and animals of the Galapagos Islands resembled (but were not the same) those of the south American coast The separation had caused a gradual change in the organisms
Charles Darwin
Where he went…
What he saw…
Existing theories of change Many people believed that each creature existed as it was created, meaning every organism today would have looked the same millions of years ago… A new Idea… Jean Baptiste Lamarck: he proposed that organisms can change over their lifetimes by the use or non-use of certain body parts Example: how the giraffe’s neck became long…
Main Points of Darwin’s Theory 1. Variations of genes exist in every population 2. In a population, some individuals are better suited for survival 3. Over time, beneficial traits tend to spread 4. The fossil record shows that living species evolved from extinct ones…
Terms to define Population Natural selection Adaptation Reproductive isolation Gradualism Punctuated equilibrium Homework: Read Chapter 13 sections 1-2 and define the above terms