Welcome Favorite Scientists! Today: Discuss Exit Ticket From Lesson 1: (If you didn’t answer this last time, do it now) How could what you learned about genetics help you understand how life on earth has changed over time? More Evidence: Selective Breeding (Artificial Selection)

Selective Breeding/ Artificial Selection

What is Breeding? To produce offspring

What is meant by being Selective? Choosing from multiple options. What music do you like?

Can you now define Selective Breeding? The process of choosing a few organisms with desirable traits to serve as the parents of the next generation. WAIT! How can you go from a skinny chicken to a giant chicken if there are no giant chickens to select?

Organisms of a species are not all the same (just look around you) Line up by height What do you notice? Groups of organisms living in an area (population) have variability in their traits So, back to chickens… –Some of the skinny chickens were bigger than others –Select those bigger “skinny” chickens (some males and some females) –Let them have babies –Will all their babies look the same? –Choose the bigger babies to continue breeding to other bigger chickens

Examples of Selective Breeding Carrots in a variety of colors

Variegated ears of maize Examples of Selective Breeding

Charolais cattle produce beef that has more red meat and less fat.

Examples of Selective Breeding Chihuahuas and Great Danes are bred for size.

Types of Selective Breeding: + Hybridization/Crossbreeding: is the process of crossing dissimilar individuals to bring together the best of both organisms.

Real Example of Hybridization: + = HorseDonkeyMule Big, Fast, Excitable Small, Slow, Calm Strong, Calm Endurance, The hybrid is often stronger and hardier than its parents: Hybrid Vigor Hybrid

Real Example of Hybridization: American horticulturist Luther Burbank ( ) developed a special potato. Burbank, while trying to improve the Irish potato, developed a hybrid that was more disease resistant. He introduced the Burbank potato to Ireland to help combat the blight epidemic. Burbank’s hybrid crosses combined the disease resistance of one plant with the food-producing capacity of another.

Types of Selective Breeding: Inbreeding: is the continued breeding of organisms with similar characteristics Breeders try to maintain certain characteristics.

Types of Selective Breeding: Mass Selection: is choosing the best plants and animals from a large number for further breeding.

What are some benefits of selective breeding? 1)Produce crops resistant to disease. 2)Produce crops that are bigger 3)Produce animals that have less fat. 4)Seedless fruit!!!

From Wolf to Dog Dogs Decoded