Chapter 24 Origin of species Flashcards
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| 276693245 | origin of species | Book of evolutionary theory published by Charles Darwin in 1859. | |
| 276693246 | biological species | individuals that can mate and produce fertile offspring | |
| 276693247 | morphological species | similar physical appearance | |
| 276693248 | speciation | An evolutionary process in which one species splits into two or more species | |
| 276693249 | 2 types of speciation | 1. allopatric speciation 2. sympatric speciation | |
| 276693250 | Allopatric | (of biological species or speciation) occurring in areas isolated geographically from one another canyon - river - mountain range - lowering sea level | |
| 276693251 | sympatric | (of biological species or speciation) occurring in the same or overlapping geographical areas | |
| 276693252 | How do you prevent the 2 newly formed species from going back to being a single species? | I prezygotic isolating mechanisms II postzygotic isolation mechamisms | |
| 276693253 | prezygotic isolating mechanisms | 1. habitat isolation 2. temporal isolation 3. behavioral isolation 4. mechanical isolation 5. gametic isolation | |
| 276693254 | habitat isolation | populations live in different habitats and do not meet ex. snakes - land/water | |
| 276693255 | temporal isolation | When two or more species reproduce at different times ex. skunk winter & summer mating | |
| 276693256 | behavioral isolation | part of reprodcutive isolation: courtship pattern is different ex. fireflies - different blink patterns | |
| 276693257 | mechanical isolation | mating does not occur due to reproductive parts not fitting together ex. dragon flies -claspers attach (mate in flight) | |
| 276693258 | gametic isolation | Sperm of one species may not be able to fertilize the eggs of another species ex. frogs sperm only swims toward egg of same species | |
| 276693259 | postzygotic isolation mechanisms | operate after fertilization has occurred to ensure that the resulting hybrid remains infertile 1. reduced hybrid viability 2.reduced hybrid fertility 3. hybrid breakdown | |
| 276693260 | reduced hybrid viability | a type of isolation where the organisms can breed, but the offspring is sterile ex. salamander | |
| 276693261 | reduced hybrid fertility | offspring are sterile ex) donkey and horse produce a MULE | |
| 276693262 | hybrid breakdown | The first-generation hybrids are viable and fertile, but when they mate the offspring are feeble and sterile ex. cotton rice |