Theory of Evolution Flashcards
Darwin’s Theory of Evolution can be broken down into what essential two parts?
Diverse groups of animals evolve from one or a few common ancestors
The process of evolution happens through natural selection
What are the five components of Darwin’s theory?
Presence of Evolution Natural Selection Common Descent Gradualism Population Speciation
Darwin’s mechanism of evolution was different from what two scientists who also supported the fact that evolution exists?
Lamarck
Buffon
Darwin’s theory of common descent implied that humans were a ______ on the __________ tree, and not a distinct _______.
branch
evolutionary
lineage
What does gradualism state?
What did gradualism imply about the Earth?
That evolution is a very slow process taking small steps over numerous generations
That it was older than previously thought
How does population speciation happen? Use an example
Random traits emerge, such as long necks in giraffes. If this is found to be beneficial, it is passed on to later generations and may form new species
What does natural selection state?
Stronger organisms will reach reproductive age and pass on their traits to offspring.
Survival of the fittest
Competition between organisms
What are the 5 postulates that natural selection depends on?
Individuals are variable
Some variations are passed on to later generations
More offspring are produced than can survive
Survival and reproduction aren’t random
History of the earth is long
What is a neutral mutation?
A mutation that does not result in any advantage or disadvantage for reproductive success
What is a harmful mutation? How does it relate to natural selection/evolution?
A mutation that decreases the reproductive success of an individual.
It will be selected against, will not accumulate over time
What is a beneficial mutation? How does it relate to natural selection/evolution?
A mutation that increases the reproductive success of an individual.
If will be favoured by natural selection and accumulate over time.
What is artificial selection? What is it used for?
Directed breeding, the choosing of individuals that have a desired trait to be parents of the next generation. Used to produces new breeds/varieties.
What is heredity?
The passing of traits from parents to offspring.
What does the phrase “survival of the fittest” describe?
Natural selection
What is catastrophism?
theory from Cuiver that global catastrophes made most species on Earth extinct. these species were fossilized and replaced with new species.
