Natural Selection Four factors: the process whereby organisms better adapted to their environment tend to survive and produce more offspring. Four factors: 1) Overpopulation: more offspring are born than can survive 2) Variation: individuals of a population have differences 3) Adaptation: Some variations allow a better chance of survival 4) Descent w/ modification: Those with advantages will reproduce and make more of the population

Examples of Natural Selection

Selective Breeding Decide which characteristics are important is the process by which humans breed other animals and plants for particular traits. How does Selective Breeding work? Decide which characteristics are important Choose parents that show these characteristics Select the best offspring from parents to breed the next generation Repeat the process continuously

Examples of Selective Breeding Wheat Producing disease-resistant wheat by crossbreeding wheat plants with disease resistance and wheat plants with a high yield. Dairy cattle Increasing milk yield by selecting bulls from high yield herds and breeding them with cows that have the best milk production. Cattle breeds The Angus bulls are selectively bred for beef.