Evolution and the Industrial Revolution David Johnson Life Science Per.4 Ms. Blackshear

Charles Darwin  Who was Darwin? –Charles Darwin was a naturalist that took a trip on the H.M.S. Beagle to the Galapagos Islands in The different animals and plants that he saw on this trip lead him to his theory of evolution by natural selection.

Evidence From the Galapagos  What did Darwin observe? –On the trip to the Galapagos Islands Darwin noticed that the finches had many different beak shapes. These differences were due to the variety of foods that the birds ate. Darwin concluded that these beaks changes in shape over time so that the birds could adapt to the environment. Being able to adapt is necessary for survival so that one can compete for resources.

Definitions  What is evolution? –Evolution is defined as the gradual change in a species over time.  What is natural selection? –Natural selection is a situation in which an organism is better adapted to its environment which makes it more likely to survive and reproduce.

Natural Selection Concept Map

Graphs of Peppered Moth Populations

What do the graphs show?  The population of light peppered moths were high before the Industrial revolution and the population of dark moths was low. Once the Industrial revolution began thick smoke and soot caused the trees where the moths rested to become darkened. This made it easier for predators to see the light moths and as a result they were more likely to get eaten by the predators than the darker moths. The variation within the species of moth allowed the darker moths to be able to survive much better than the lighter moths and as a result their population grew.