Section 1 - Evolution Flashcards
What is Evolution?
Genetic change over time
Evolution is a ______ _______ in biology
Unifying theme
Who originated the theory of evolution?
Charles Darwin.
What is the main cause of evolution?
Natural Selection
Evolution is also termed “________ ____ ______________”
Descent with modification
What are the smallest units that can evolve?
Populations
What is Speciation?
Evolution of reproductive barriers
What are the two categories of speciation?
Pre-zygotic and Post-zygotic
What are some Pre-zygotic isolating mechanisms?
Ecological isolation - species occupy different habitats in the same area
Behavioral isolation - species differ in mating rituals
Temporal isolation - species reproduce at different times
Mechanical isolation - structural differences prevent mating
Prevention of gamete fusion - gametes of one species function poorly with gametes of another species
What is an example of a Post-zygotic isolating mechanism?
Offspring infertility or inviability
What is allopatric speciation?
Speciation caused by a geographic barrier
i.e. A canyon or body of water separating the two populations
What is Sympatric speciation?
Speciation that occurs when populations are living together
Macro evolution is
Evolutionary change substantial enough to create a new genera or higher
What is adaptive radiation?
When evolution creates divisions of a species that fill different ecological niches
