Evolution and Selective Breeding
No description yet. This curated deck is ready for daily study.
Card preview (5)
(DON’T NEED)Why was the theory of evolution rejected by most people?
• It went against the religious belief that God created life • Darwin couldn’t explain how the useful characteristics were passed on from a parent to an offspring because he didn’t know anything about genes or mutation • There wasn’t enough evidence to convince people
(DON’T NEED)What was Jean-Baptiste Lamarck’s theory?
Changes that an organism gets during its lifetime are inherited by its offspring
What is selective breeding?
• From your existing stock, pick the ones with the characteristics you want • Breed them together • From their offspring choose the ones with the characteristics you want and breed them together • Continue for several generations and eventually all the offspring will have the characteristics
What is selective breeding used for?
• Animals that produce more meat or milk • Crops with disease resistance • Dogs with desired characteristics
What are the problems with selective breeding?
• It reduces the gene pool (the number of different alleles in a population). This is because the farmer picks from the “best” which have all the same alleles. So if there is a disease that can kill an individual, there’s not much variation in the rest of the population so the rest of the population may die from the disease too. • Inherited defects • Inbreeding, some breeds are particularly prone to disease