What Darwin Never Knew: NOVA
Earth teems with a staggering variety of animals, including 9,000 kinds of birds, 28,000 types of fish, and more than 350,000 species of beetles alone. What explains this explosion of living creatures-1.4 million different species discovered so far, with perhaps another 50 million more to go? The source of life’s endless forms was a profound mystery until Charles Darwin’s revolutionary idea of natural selection, which he showed could help explain the gradual development of life on earth.
The Peppered Moth
For years the story of the peppered moth, Biston betularia, has provided one of the best-known examples of natural selection in action.
Natural selection is the engine that drives evolution. The organisms best suited to survive in their particular circumstances have a greater chance of passing their traits on to the next generation. But plants and animals interact in very complex ways with other organisms and their environment. These factors work together to produce the amazingly diverse range of life forms present on Earth.
Evidence for Evolution
Download the Notes from class on the
Evidence for Evolution here --->
Play a game show based on the rules of Natural Selection
Peppered Moth Interactive
Darwin's Finches Interactive
How did the finches change?
Click on this link (or the picture) to watch the interactive about Darwin's discovery of the Galapagos Finches.
Questions to think about:
1. What trait of the finches were the scientists studying?
2. How were the birds different from each other? (Variation)
3. What happened to the environment on the island?
4. How did the population of the finches change?
5. What was the beneficial trait that allowed some finches to survive?
6. Predict: What would happen to the population of finches if the environment changed again on the Island?