Changes Over Time. SOL: BIO 8 a-e . Standard BIO 8 a-e The student will investigate and understand how populations change through time. Key concepts include: a) evidence found in fossil records;
SOL: BIO 8 a-e
The Father of Evolution
Carolus Linnaeus (1707 – 1778)
Believed in the “Fixity of Species”
Charles Lyell’s view of the process of formation of sedimentary rock
Who was Linnaeus?
Who was Lyell?
If Lyell looked at fossils is a cross section of sediment, would the fossils more towards the surface be older or younger than those below? Why?
At the age of 22, he joined a 5 year expedition aboard the HMS Beagle to map the coast of South America
1. Members of a population have heritable variations.(Inheritance of traits)
2. In a population, more individuals are produced than the environment can support. They compete for food and shelter. (overpopulation- struggle for survival).
3. Some individuals have adaptive characteristics that enable them to survive and reproduce better than other individuals (survival of the fittest).
4. An increasing number of individuals in succeeding generations have these adaptive characteristics (natural selection)
Summarize the four components of Darwin’s theory of evolution.
Darwin described his theory in the form of a long essay which he called
“On the Origin of Species”.
Concerned about the public’s response to his ideas(remember what happened to Galileo)
Arranged to publish his work … AFTER HIS DEATH !!
At age 50 (1859)
At age 65 (1874)
What was the name of Darwin’s book?
On what island did Darwin make observations that lead him to develop his ideas about natural selection?
Explain how natural selection can be observed in a population.
A mutation may result in a:
1.favorable change or adaptation in genetic information that improves a species’ ability to exist in its environment
2. an unfavorable change that does not improve a species’ ability to exist in its environment.
3. in a change in the genetic information that neither harms nor helps the species.
Thousands tomillions of yearsof natural selection
Example of artificial selection in plants: five vegetables derived from wild mustard
Hundreds tothousands of yearsof breeding(artificial selection)
Chromosome with geneconferring resistanceto insecticide
Additionalapplications of thesame insecticide willbe less effective, andthe frequency ofresistant insects inthe populationwill grow
What is evolution?
Identify the four processes of evolution. Explain how each process can lead to evolutionary change.
Scorpion in amber
EX.: appendix in humans, whale pelvis, tiny snake pelvic and limb bones, and the eyes in cave-dwelling salamanders and fish that are completely blind.