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Chapter 22
"The Origin of Species" Evolutionary Biology, BIOL 152 CSU Chico
| Question | Answer |
|---|---|
| sympatric | species that occur together |
| gene pools | all alleles present in a species |
| biological species concept | "...groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups." |
| reproductively isolated | populations whose members do not mate with each other or who cannot produce fertile offspring |
| reproductive isolating mechanisms | prevent genetic exchange between organisms |
| prezygotic isolating mechanisms | prevent the formation of zygotes |
| pheromones | chemical signals |
| reinforcement | improvement of isolating mechanisms resulting in complete reproductive isolation |
| polyploidy | produces individuals that have more than two sets of chromosomes |
| autoploidy | all of the chromosomes come from a single species |
| allopolyploidy | two species hybridize |
| adaptive radiation | groups of closely related species that have recently evolved from a common ancestor and have adapted to their environments |
| key innovation | evolves within a species allowing it to use resources that it couldnt use before |
| gradualism | evolution occured very slowly |
| stasis | little or no evolutionary change |
| punctuated equilibrium | long periods of stasis punctuated with small bursts of evolution |