Week 7 Flashcards
What are the 4 keys mode of speciation?
Allopatric speciation
Parapatric speciation (founde effect)
Parapatric speciation
Sympatric speciation
Describe Allopatric speciation:
Allopatric speciation is the evolution of genetic reproductive barriers between populations that are geographically separated by a physical barrier
Describe Peripatric Speciation:
A new species is formed from the isolation of a small peripheral isolated population.
Describe sympatric speciation:
It may occur from some sort of disruptive selection in which certain genotypes have a preference for distinct microhabitats where mating takes place.
What are contact zones?
Zones in which allopatric speciated species come in contact again without interbreeding.
Describe species replacement:
Related species replace one another geographically reflecting allopatric origins.
How can parapatric speciation occur?
Can theoretically occur if gene flow, between populations that occupy adjacent regions with different selective pressures, is much weaker than divergent selection for different gene combinations.
What’s a Polyploid?
An organism with more than two complements of chromosomes.
How are Autopoyploid formed?
By the union of unreduced gametes from genetically and chromosomally compatible individuals.
What’s and Allopolyploid?
Is a derivative of a partly sterile diploid hybrid.
What is an Analogous similarity?
Similarity that has evolved due to convergence evolution, not common ancestry. It’s functional.
What is an Homologous similarity?
Similarity that has been inhertied by a common ancestor and it’s not always functional
