Flashcards in Chapter 24 Deck (14):
What is required for the formation of new species?
Absence of gene flow
What are the 2 types of barriers?
What are the types of prezygotic barriers?
What occurs in habitat isolation?
Two species occupy different habitats
How does mechanical isolation occur?
Morphological differences prevent 2 species from mating
How does gametic isolation occur?
Sperm is not able to fertilize egg
What are the types of postzygotic barriers?
-Reduced hybrid viability
-Reduced hybrid fertility
What are the 2 main ways that speciation can occur?
What are the 3 mechanisms that can lead to sympatric speciation?
What is polyploidy? What are the 2 types of polyploids?
-Condition that results in extra chromosomes
-Autopolyploid (all from same species) and allopolyploid (sets deriving from different species
What is a hybrid zone?
Area in which different species meet and mate
What are the 3 possible outcomes when 2 related species meet and mate in a hybrid zone?
-Strengthen reproductive barriers
-Weaken reproductive barriers
-Continued formation of hybrids
Period of stasis for organism followed by sudden change