Speciation & Reproductive Isolation

Question 1

types of speciation (3)

Answer 1

adaptive radiation, sympatric speciation, allopatric speciation

Question 2

isolating mechanisms (2)

Answer 2

reproductive and geographic

Question 3

geographical barriers ex.

Answer 3

mountains, canyons, ex. squirrels on either side of the grand canyon led to two different types of squirrels

Question 4

prezygotic reproductive isolating mechanisms (4)

Answer 4

habitat preference, behavioral incompatibility (sexually active at different times), physiological incompatibility (sperm and egg may fail to unite), structural incompatibility (unmatchable sex organs

Question 5

postzygotic reproductive isolating mechanisms (3)

Answer 5

hybrid inviability (the egg may fail to develop properly), hybrid sterility (the offspring may be viable but infertile), hybrid breakdown (first gen is fertile but not second gen)

Question 6

allopatric speciation

Answer 6

populations become geographically separated and then become reproductively isolated due do different environmental circumstances

Question 7

types of sympatric speciation (3)

Answer 7

polymorphism (ex. camouflage insects can only breed with other insects of the same colour), polyploidy (when an individual has more than 1 pair of a chromosome due to non-disjunction), hybridization (when two reproductively isolated species mate and create a hybrid)

Question 8

adaptive radiation

Answer 8

the rapid evolution of many species from an ancestral species ex. when a species colonizes a habitat with many available ecological niches, it will change to fit those niches, creating more species