Term
| Three types of speciation |
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Definition
| allopatric, parapatric, and sympatric |
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Term
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Definition
| the creation of two different species as the resutlt of geographic boundary |
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Term
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Definition
| Must have an initally large population. A small group of individuals leave the large population and colonize a new area that is geographically or physically separated from the original population. Due to chance, or genetic drift, the genetic composition of the small colony differs from the large population. Because of these diferences, the two populations are reproductively isolated when they come back in contact with each other. |
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Term
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Definition
| reproductive isolation develops and a new species arises without geographic isolation |
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Term
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Definition
| Starts with one large, randomly mating population. differences among individuals cause them to choose different habitats and mates. Habitat spevialization and non-random mating cause individuals to become genetically different. Eventually, two spevies coexist. |
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Term
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Definition
| new species evolve from a contiguous population |
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Term
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Definition
| Two neighboring populations live in different environments (could be as a result of overpopulation so the individuals spread out and start new colonies). The environment of A might be hotter or dryer than A'. Natural selection favors different genotypes in the two environments; the two populations become genetically different. The populations interbreed and form a hybrid zone. Hybrids have low fitness so the two populatiosn become reproductively isolated to form Species A and Species B. |
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Term
| biological species concept |
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Definition
| defines a species as a population or group of populatiosn whose member have the potential to interbreed and produce fertile offspring. centers on sexual reproduction. Species that fit this definition are also refrerred to as "sexual species" |
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Term
| Limitations of biological species concept |
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Definition
| Can only be applied when organisms are reproducing sexually, not extinct, and not geographically isolated |
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Term
| Evolutionary species concept |
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Definition
| catagorizes organisms as species based upon genealogy or line of descent. Its dependant upon unique geno/pheno feature, can be sexual or asexual, lineage must be recognizably distinct from all others, reproductive isolation is often used here as well. |
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Term
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Definition
| the arrival of a new species, determined using the criteria of either the BSC or ESC. The newly evolved species doesn't or can't mate with the parent species. They are blocked by some sort of barrier, which can be reproductive or environmental. |
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Term
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Definition
| keep closely related populations from interbreeding even when their ranges overlap. Two types: prezygotic, and postzygotic. |
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Term
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Definition
| prevents fertilizing between two species. There are five types: temporal isolation, habitat isolation, behavioral isolation, mechanical isolation, and gametic isolation. |
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Term
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Definition
| isolation of a species that occurs when two species breed at different times of the year |
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Term
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Definition
| species isolation that occurs when two species live in the same area but not in the same kinds of places |
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Term
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Definition
| speciation that occurs because there is little or no attraction between the males and females of the opposite species |
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Term
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Definition
| occurs when female and male sex organs are not compatible. |
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Term
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Definition
| two members of differing species may copulate but the gametes do not unite to form a zygote |
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Term
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Definition
| barriers that operate after the hybrid zygotes are formed. three types: hybrid inviability, hybrid sterility, and hybrid breakdown |
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Term
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Definition
| genes of the two parents are not compatible; therefore hybrids will not survive |
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Term
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Definition
| hybrids reach maturity but they do not possess the ability to reproduce |
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Term
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Definition
| the first generation of hybrids are vital and fertile, but when they reproduce, the second generation hybrids are feeble and sterile |
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