[01:119:115] - Final Exam Guide - Comprehensive Notes fot the exam (33 pages long!)

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Microevolution: changes in allele frequency in populations over generations. Dendrobium, genus of orchids-flower on different days, only open for. 1 day: behavioral isolation: species-unique enable mate recognition, ex. Common in aquatic organisms release gametes into water: prozygotic barriers: operate after fertilization occurs, reduced hybrid viability: embryo dies early in development, ex. Overlapping salamander species sometimes hybridize, rarely develop: reduced hybrid fertility: hybrids are viable, but sterile or low fertility, most likely due to problems during meiosis, ex. Mule-female horse (2n=64) + male donkey (2n=62: hybrid breakdown: 1st generation hybrids are viable and fertile, hybrids can mate with each other or parent species, resulting offspring are infertile or frail. Crickets in hawaiian islands: chance events: random events can isolate sub-populations, ex. North american apple maggot fly: habitat isolation temporal isolation postzygotic barriers, extremely common. High species diversity: low environmental diversity high environmental diversity rapid diversification, environmental change change selective pressures biological change, ex.