Unit 4 - Speciation and Tree Thinking Flashcards
What is speciation
The evolutionary process leading to the formation of new species.
____ are the lowest taxonomic rank.
Species
Reproductive isolation causes the cessation of ____ between populations.
Gene flow
How do prezygotic barriers block fertilization?
Prevents different species from mating altogether, prevents completion of mating, or prevents fertilization if mating is successful
What are the prezygotic barriers?
Habitat isolation, temporal isolation, behavioral isolation, mechanical isolation, and gametic isolation.
What are the postzygotic barriers?
Reduced hybrid viability and reduced hybrid fertility.
What is a zygote?
The diploid cell produced by the union of haploid gametes during fertilization.
Species that breed at different times of the day, in different seasons, or different years do not ______
Interbreed.
What are postzygotic barriers?
They prevent hybrid zygotes from developing into viable, fertile adults.q
What is the morphological species concept?
It distinguishes a species by its structural features.
What is the ecological species concept?
Defines a species by its interactions with the living and nonliving parts of the environment.
What is the biological species concept?
Emphasizes the separateness of different species due to reproductive barriers.
What is micro evolution?
Evolutionary change below the species level.
What is macro evolution?
Evolutionary change above the species level.
What is speciation?
An evolutionary process in which one species splits into two or more species.
What is allopatric speciation?
Populations that are geographically isolated.
What is sympathies speciation?
Populations that are not geographically isolated.
Reproductive isolation is a by-product of genetic differences between populations. Therefore, we would generally expect gene flow to ____ speciation.
Impede
What is geographic separation?
Creates two populations of the same species who are isolated from each other, not allowing genetic exchange between them.
What is vicariance?
When a population is divided into geographically isolated subpopulations.
What is dispersal?
When individuals colonize a remote area.
