Evolution Review- Charles Darwin
The Bean Lab
A model that represents natural selection. Pinto beans, split peas, lentils, and rice are put in a bowl with holes in the bottom. These holes are different shapes and sizes. The beans represent different variations within a species. The bowl represents the environment. The holes represent challenges, such as predators and climate change. The beans are put in the bowl. The bowl is then shaken for 10 seconds. Beans that fall through the holes are "dead." Those that don't multiply and continue. After doing this 5 times, the beans that "survived" represent adaptations. The others represent variations that didn't assisst survival because they were unable to adapt to the challenges of the environment.
Adaptive Radiation
A type of natural selection where one species spreads to several different environments. These organisms adapt to their new environments. The result is that multiple species can evolve from a single original species. One example of natural selection are the finches that Charles Darwin found on the Galapagos Islands. Most of them most likely started with one species of finch, however, the finches were scattered throughout the islands. Because of the completely different environments on each island, many new species evolved to adapt to the islands they live on.
The Voyage
Charles Darwin's 5-year voyage on the HMS Beagle lasted from 1831 to 1836. During this voyage, Darwin collected thousands of specimens to be analyzed. The captain of the Beagle was Robert FitzRoy. The main purpose of the voyage was actually to observe the coasts of other continents. It started in England, then went down to Africa, went around the coast of South America to Australia, then back to England.
Steps of Natural Selection
Example species: marine iguanas. Step 1: More iguanas are produced than the environment can support. Step 2: Some iguanas have variations due to genetics. Step 3: The variations that are most helpful for survival are called adaptations. The iguanas with adaptations are more likely to survive, reproduce, and pass on their traits. Step 4: After a long period of time, a new species of iguana (marine iguanas) could evolve.
The Origin of Species
The book written by Charles Darwin about his theories on natural selection.
Charles Darwin
Was a naturalist. He was the first person to seriously consider natural selection. He wrote a book about it. Writing and publishing the book took 23 years. Spent 5 years on a voyage on the HMS Beagle. He lived from February 12, 1809 to April 19, 1882. He was married to his cousin, Emma Wedgewood, who was very religious. This created some problems, as Darwin's ideas were against religious belief. They had 10 children. He studied organisms throughout the world, including in the Galapagos Islands.