| What is microevolution? | evolutionary change over a short period of time (small changes within a population of organisms) - humans getting taller, bacteria evolving antibiotic resistance |
| What is macroevolution? | major evolutionary changes, e.g. resulting in new species being formed - algae evolving into land plants, aquatic invertebrates evolving hard shells |
| What kinds of speciation are there? | Reproductive isolation
Allopatric
Sympatric |
| What is Reproductive isolation? | Causes barriers to gene flow and the production of viable offspring |
| What is Allopatric Speciation? | Speciation that occurs when the gene flow between populations is interrupted by a geographical barrier |
| What is Sympatric Speciation? | Speciation that occurs when there is no geographical barrier to interrupt gene flow between population. |
| What are two types of Reproductive Isolation? | Prezygotic and Postzygotic |
| What is Prezygotic reproductive isolation? | those that inhibit reproduction before fertilization |
| What is Postzygotic reproductive isolation? | those that inhibit reproduction after fertilization |
| What are some Prezygotic barriers? | Habitat Isolation
Temporal Isolation
Behavioural Isolation
Mechanical Isolation
Gametic Isolation |
| What is Habitat Isolation? | different species need different conditions to survive |
| What is Temporal Isolation? | Prevents species to mate because they breed at different times. |
| What is Behavioural Isolation? | if courtship behaviors are too different, then the individuals don't recognize each other as potential mates |
| What is Mechanical Isolation? | When the reproductive organs of a species are elaborately shaped and are only able to engage with those of same-species organisms |
| What is Gametic Isolation? | The gametes (egg and sperm) come into contact, but no fertilization takes place. Gametes may be unable to recognize one another in different species |
| What are the Postzygotic Barriers? | Reduced hybrid viability
Reduced hybrid fertility
Hybrid breakdown |
| What is Reduced hybrid viability? | A lower potential to survive for
organisms whose parents have incompatible genetics, mostly because these
parents mated despite being different species |
| What is Reduced hybrid fertility? | Two different fertile species mate to produce sterile offspring |
| What is Hybrid Breakdown? | S type of reproductive failure that appears after the F2 generation of
crosses between different species or subspecies. |
