Evolution Flashcards
What did Cuvier contribute to early evolutionary thinking
Catastrophism was the theory that the Earth had largely been shaped by sudden, short-lived, violent events, possibly worldwide in scope.
What did Lyell contribute to early evolutionary thinking
Uniformitarianism is the theory that earth has been changed by the same processes in the past as can be observed occurring in the present day (erosion = grand canyon)
It also stated this was slow and gradual, not sudden
Lastly, it said natural laws are constant and eternal and operate with the same intensity in past and present
What was Thomas Malthus theory, how did it help Darwin?
His theory was that population growth expanded in times and in regions with lost of resources until the size of the population relative to the primary resources caused distress. After this, it balanced out over time.
What are the components of Darwin’s theory of natural selection?
- More individuals are made than can survive
- Phenotypic variation exists among individuals and it’s heritable
- individuals with heritable traits better suited to their environment survive
- When reproductive isolation occurs, new species will form
Whats Lamarck’s theory of natural selection?
Theory of inheritance: If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring.
What are 3 things you would look at to determine common ancestry [Phylogenetic Tree]
Anatomical Structures -HomoloAnalogVistig [HAV] Embryological Development early stages are similar in closely related species Genetics similarities in proteins or genetic code
What are homologous features?
Different purpose similar structure
[Human arm - Bat Wing]
What are analogous features?
Same function, Different form
[Bird wing - Insect Wing]
What are vestigial features?
Features that no longer share a purpose
[Wisdom Teeth]
What are the 3 types of mutations and which one drives evolution forward?
Neutral mutatuion
Harmful Mutation
Benificial Mutation [helps evolution]
What has to occur in order for speciation to occur
Isolation
Describe allopatric speciation. Whats 1 example?
This is location based, An earthquake causes a crack to split a group of sheep
Describe sympatric speciation. Whats 1 example?
This is anything but location based
What is a prezygotic reproduction isolating mechanism?
What are the different types?
A mechanism that doesn’t allow the egg to be fertilized
Temporal - Timing
behavioral - mating dance etc
Ecological - location
Gametic
What is a postzygotic reproduction isolating mechanism?
What are the different types?
Prevents the formation of fertile offspring
Zygotic mortality - All offspring will be a misscariage
Hybrid inviability - Won’t survive long after birth
Hybrid infertility - offspring is infertile
