Isolating Mechanisms Flashcards
What are isolating mechanisms?
Mechanisms that do not allow different species to successfully interbreed
What are the 3 Isolating mechanisms?
- Geographical isolation
- Prezygotic Isolation
- Postzygotic isolation
What is a zygote?
The fertilised egg
What does prezygotic isolating mechanisms refer to?
Isolating mechanisms that occur before fertilised egg is conceived
Give the 6 prezygotic isolating methods
- Geographical (spacial)
- Ecological
- Temporal
- Behavioural (sexual selection)
- Structural (morphological)
- Gamete mortality
Describe Geographical (spatial) prezygotic isolating mechanism
If not in the same geographical location than can’t interbreed
Describe Ecological prezygotic isolating mechanism
Not in the same habitat (eg: lives on ground or pond or tree)
Describe Temporal prezygotic isolating mechanism
Not active during same time of the day
Descrive behavioural (sexual selection) prezygotic isolating mechanism
Mating rituals ensure behaviours are compatible
Describe Structural (morphological) prezygotic isolating mechanism
Ken is TOO BIG!!
Genitals are not compatible/complementary
Describe gamete mortality prezygotic isolating mechanism
Gametes from male are destroyed inside female reproductive tract
What does postzygotic isolating mechanisms refer to?
Isolating mechanisms that apply after fertilised egg is conceived
State the 3 postzygotic isolating methods
- Zygote mortality
- Hybrid mortality
- Hybrid sterility
Describe Zygote mortality postzygotic isolating mechanism
Fertilised egg doesn’t divide and eventually it dies
Describe hybrid inviability postzygotic isolating mechanism
Embryo miscarries
