13-1 Notes Selective Breeding Popcorn was one of the first organisms humans improved for our own benefit. Corn as we know it was first grown as a crop at least 6000 years ago by Native Americans living in what is now Mexico. This idea of choosing what we “make” started with Popcorn!! Europeans started breeding the plants for larger kernals, eventually it turned into the corn we know today! (remind them about Gregor Mendel)
How we’ve used Selection Dogs- Tiny Chihuahuas and Huge Great Danes Labrador retrievers with short coats and poodles with curly hair. Humans are always looking to make animals that are better hunters, better retrievers or more capable of producing a quality product. Selective Breeding: so labrador breeders have bred for retrieving capabilities and companionship, whereas poodle breeder breed for curly hair and temperament (it also happens to be hypoallergenic). What would happen if we bred a labrador with a poodle? Labradoodle!! Looking at our vocabulary words, what is this called? Yes, lets all say hybridization on the count of three!
Selective Breeding- letting only those animals with desired characteristics produce the next generation. The two most common methods of selective breeding are hybridization and inbreeding. So as we’ve seen in our examples ….
Hybridization Crossing organisms that have different traits to bring together the best of both organisms. Offspring made by such crosses are called hybrids. Often hardier than parents. Results are new organisms that have traits farmers need to make more food. Hereford cattle are larger framed (easier calving) and better mothers, Angus cattle are more desirable (the black color is desirable to market)
How it all Started Luther Burbank may have been the greatest selective breeder of all time. Developed more than 800 kinds of plants Burbank used Hybridization. Many of Burbank’s hybrid crosses mixed the disease resistance of one plant with the food-making ability of another. The Burbank Plum- in 1890 he made a hybrid plum out of many seedlings from all over the world-still used today! Huge effect on American Agriculture. Santa Rosa Plum, wickson plum
Inbreeding Continued breeding of individuals with similar characteristics. Many breeds of dogs Inbreeding helps keep the characteristics that make each breed unique and helps make sure that those characteristics are preserved. Inbred organisms are genetically very similar and can increase the probability that organisms may inherit genetic disorders. Example- inherited hip problems are common to many breeds of dogs. German Shephards, Saint Bernards. Lethal Whites in Paint horses, Red Angus Cattle get a bone fusion deal.
Key Question: Answer on your notes using complete sentences What is selective breeding used for? Please answer this question in your notes: Pair, share.
Ticket out The Door 1. Crossing individuals with different traits to bring together their best characteristics is called a. domestication b. inbreeding c. hybridization d. polyploidy 2. Crossing individual with similar characteristics so that those characteristics will appear in their offspring is called a. inbreeding b. hybridization c. recombination 3. Taking advantage of naturally occurring variation in organism to pass wanted traits on to future generations is called a. selective breeding b. forensics c. gene therapy d. mutation