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Speciation:

the process by which one species splits into two or more species

Species:

a

population/group of populations whose members have the potential to

interbreed in nature and produce viable, fertile offspring with members

of other populations

interbreed and produce viable and fertile offspring

biological species defines a species is a group of populations whose members interbreed and produce viable, fertile offspring

morphological species

characterizes a species by body shape and other structural features (same morphology)

phylogenetic species

defines a species as the smallest group of individuals that share a common ancestor (same evolutionary history)

ecological species concept

views a species in terms of its ecological niche, or its role in the environment (same ecological role)

prezygotic barrier

block fertilization from occurring

habitat isolation

when two species encounter each other rarely because they occupy different habitats

temporal isolation

when species that breed during different times of the day, season, or year cannot mix their gametes

behavioral isolation

courtship rituals and other behaviors unique to a species are effective barriers

mechanical isolation

morphological differences can prevent successful mating

gametic isolation

sperm of one species may not be able to fertilize eggs of another species

postzygotic barrier

prevent the hybrid zygote from developing into a viable, fertile adult

allopatric speciation

gene flow is interrupted when a population is divided into geographically isolated subpopulations

sympatric speciation

speciation occurs in populations that live in the same geographic area

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