Darwin’s Voyage(Set up for Cornell Notes)

Darwin’s Observations• Charles Darwin was an English

naturalist who developed the “Theory of Evolution by Natural Selection.”

• Darwin went on the HMS Beagle around the world in the 1830’s and observed animals.

• Species: group of similar organisms that can produce fertile offspring.

Similarities and Differences

• Darwin observed how many organisms are similar yet have important differences.

Adaptations

• An adaptation is a trait that helps an organism survive and reproduce.

Evolution

• Evolution is the gradual change in a species over time.

• Scientific Theory: well tested idea that explains a wide range of observations.

• People use selective breeding to obtain desired traits in crops and animals.

Natural Selection

• Natural selection is the process where individuals that are better adapted are more likely to survive and reproduce, than members of the same species.

• Overproduction: making more offspring than can possibly survive.

• Competition: competing for limited resources.

• Variation: differences between members of the same species

• Over a long period of time, natural selection can lead to a gradual accumulation of + traits and the disappearance of – traits.

The Role of Genes in Evolution

• Only traits controlled by genes can be affected by natural selection

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How do new Species form?• Geographic isolation = individuals

remain separated from the rest of their species long enough to develop new traits.

Continental Drift

• Continental drift is geographic isolation that occurred on a massive world-wide scale.