Chapter 22: Descent with Modification - Evolution and Adaptation through Natural Selection, Study notes of Biology

Download Chapter 22: Descent with Modification - Evolution and Adaptation through Natural Selection and more Study notes Biology in PDF only on Docsity! Chapter Learning Objectives Chapter 22: Descent with Modification: a Darwinian View of Life  Define evolution and adaptation.  Evolution- a descent with modification that produces the observed pattern of change.  Adaptation- inherited traits of organisms that improve their survival and reproduction in specific environments. Concept 22.1: The Darwinian revolution challenged traditional views of a young Earth inhabited by unchanging species  Describe the theories of catastrophism, gradualism, and uniformitarianism. a. Catastrophism- the principle that events in the past occurred suddenly and were caused by mechanisms different from those operating in the past. For example, hurricanes Georges Cuvier b. Gradualism- for example, valleys were often formed by rivers wearing through rocks and that rocks containing marine fossils were formed when sediments that had eroded from the land were carried by rivers to the sea, where they buried dead marine organisms. James Hutton c. Uniformitarianism- states that mechanisms of change are constant over time, Charles Lyell  Explain the mechanism for evolutionary change proposed by Jean-Baptiste de Lamarck  Use and disuse principle- idea that parts of the body that are constantly used grow larger and stronger, and the others just deteriorate. (Use it or lose it)  Inheritance of acquired characteristics- an organism can pass these enhancements to its offspring; a son getting his dad’s strong arms Concept 22.2: Descent with modification by natural selection explains the adaptations of organisms and the unity and diversity of life  Explain the mechanism for evolutionary change proposed by Darwin in On the Origin of Species.  The unity of life, diversity of life, and the match between organisms and their environment. Descent with modification which means that organisms share many traits that connect us all. Led to the rich diversity of life. Also discussed the tree of life, with branches to compare different characteristics and the stem to connect us all.   Describe the two inferences Darwin made from his observations that led him to propose natural selection as a mechanism for evolutionary change.  Inference 1- People who have inherited traits that help them survive and reproduce tend to leave more offspring than regular people.  Inference 2- Inequality to survive and reproduce will lead to favored traits in the population over generations (ex. Long hair on black girls).  Distinguish between artificial selection and natural selection  Artificial selection- picking and choosing which traits you want. (like gene selection)  Natural selection- individuals that have special inherited traits tend to survive and reproduce faster than normal people. (Superheroes tend to live longer than humans because of traits)  Explain why an individual organism cannot evolve  It is the population that evolves Concept 22.3: Evolution is supported by an overwhelming amount of scientific evidence  Describe the observations of soapberry bugs that supported Carroll and Boyd’s hypothesis that changes in a population’s food source can result in evolution by natural selection  Soapberry bugs feed on the balloon vine fruit, but the beaks are different based on how thick the seeds are in the fruit. For example, the first species of bugs had short beaks, then as the plant seeds got thicker; natural selection resulted in the evolution of the beak length.  Explain how drug resistance develops in bacteria and viruses  A few drug resistant viruses were present and become present and natural selection increased their frequency. Also, the virus can colonize hosts, and increase disease severity.  Explain how the existence of homologous and vestigial structures can be explained by Darwin’s theory of natural selection.