Speciation

Flashcards about Speciation

Species

A group of organisms that interbreed to produce fertile offspring.

Reproductive Barriers

Isolating mechanisms that prevent interbreeding.

Prezygotic

Isolating mechanisms that occur before mating.

Postzygotic

Isolating mechanisms that occur after mating.

Habitat Isolation

Organisms cannot reproduce because they are in different environments.

Temporal Isolation

Organisms mate at different times.

Behavioral Isolation

Unique behavior and mating rituals.

Mechanical Isolation

When parts don't fit, preventing reproduction.

Gamete Isolation

Sperm can't fertilize egg.

Zygote Mortality

Fertilization occurs, but zygote doesn't live.

Hybrid Sterility

Hybrid survives but can't reproduce.

F2 Sterility

Hybrid can reproduce (F1), but its offspring can't.

Allopatric Speciation

Geographic isolation leads to species evolving differently.

Adaptive Radiation

Evolution from one ancestor by adapting to different environments.

Sympatric Speciation

Speciation in the same place, but other barriers appear.

Polyploidy

Occurs when chromosome number goes higher than 2n (usually in plants).