Mechanisms of Speciation

prezygotic isolation

prevents mating or fertilization from happening

postzygotic isolation

mating occurs, but offspring are infertile

hybrite sterility

the hybrid offspring develops but is sterile

what is hybrid inviability?

the embryo does not develop properly or dies at an early age due to genetic incompatibility

hybrid break down?

The first generation hybrids maybe fertile but it’s offspring are weak, infertile or inviable.

what is temporal isolation?

Species reprouce at different times e.g seasons, months or times of day. the species don’t come in contact with one another.

behavioral isolation?

Differences in mating behaviours, such as courtship rituals or mating calls prevents attraction between species.

Habitat isolation

Species live in the same habitat but occupy different habitats and rarely encounter each other.

mechanical isolation

physical differences in reproductive structures prevent successful mating

gametic isolation

even if mating occurs, sperm and egg cannot fuse due to genetic or chemical incompatibility.

sympatric geographic isolation

A new species evolves from one common ancestor while being in the same geographical area. These species don't interbreed due to niche differences

geographical isolation involve?

Physical barriers scuch as rivers, oceans, mountains that seperate a populartion into 2 groups. Overtime they involve independently due to different environmental pressures and mutations.