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Speciation Barriers

Species that live in the same region are prevented from mating because they live in different habitats. Ecological Isolation
Species breed at different times of day, during different seasons, or even during different years. Temporal Isolation
Unique mating behaviors or rituals prevent mating among different species. Behavioral Isolation
Physical differences in different species’ sex organs prevent successful mating. Mechanical Isolation
The sperm of one species can’t fertilize the eggs of another species. Gametic Isolation
Genes from different parent species impair the development and survival of hybrids. Reduced Hybrid Viability
Chromosome numbers of the two parent species are different, therefore meiosis in the hybrid does not produce normal chromosome numbers in the gametes. Reduced Hybrid Fertility
Fertile hybrids are produced in the 1st generation, but 2nd generation offspring are weak and sterile. Hybrid Breakdown
A barrier that prevents two species from mating before a zygote is formed. Pre-zygotic barrier
A barrier that prevents a hybrid from surviving or reproducing (occurs after a zygote has formed between two species). Post-zygotic barrier
The offspring of two different species. Hybrid
The formation of new species. Speciation
A group of similar organisms that can mate and produce fertile offspring. Species
Species are found in different areas separated by a physical barrier. Geographic Isolation
Created by: ballb