E5 - Types of Evolution Flashcards
species
all members of a population who can breed with one another under natural conditions
-AND whose offspring can do the same
TRUE IR FALSE:species continuously evolve
TRUE
When evolution leads to the evolution of an entirely new species, we call this….
speciation
Reproductive Isolation
For a new species to form, individuals from the original species must evolve to become reproductively isolated from the remainder of the population
This would also involve a new independent population that can breed with one another
reproductive isolating mechanism
any factor which prevents two populations from interbreeding while in the same region
What is one way for a species to split into 2
-populations to seperate geographically
-changes in the sae trait keep speicies reproductivel isolated
ex. if lizard were in hot enviroment their dewlaps would change ti red
-males left with yellow dewlaps would not be recognzied by femakes, therefore reproductively isolated
Reproductive Isolating Mechanism: Prezygotic
Reproductive isolating mechanisms may be classified as a prezygotic mechanism
-are mechanisms that prevent fertilization and zygote formation
Reproductive Isolating Mechanism: Prezygotic: Behavioral isolation
- using diff courtships
Reproductive Isolating Mechanism: Prezygotic: temporal isolation
diff species breed at diff times of year
Reproductive Isolating Mechanism: Prezygotic: ecological isolation
similiar species occupy diff habitats within a reigon
Reproductive Isolating Mechanism: Prezygotic: mechanical isolation
diff features lead to incompatability
Reproductive Isolating Mechanism: Prezygotic: gamte isolation
male gamete may not recognize and fertilze egg
Reproductive Isolating Mechanism: Postzygotic
Reproductive isolating mechanisms may be classified as a postzygotic mechanism
-are mechanisms that prevent a fertilized egg from growing into a viable adult
**Viable means capable of sustaining life
Reproductive Isolating Mechanism: Postzygotic: zygotic mortality
-mating possible but gentic diff may cause zygote to not form properly
Reproductive Isolating Mechanism: Postzygotic: hybrid inviabvility
hybrid indivdual devleopes but dies before birth or dies before maturing