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| 13598535166 | convergent evolution | the independent evolution of similar features in different lineages |  | 0 |
| 13598535167 | population | a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring |  | 1 |
| 13598535168 | founder effect | when a individuals become isolated from a larger population, this smaller group may establish a new population whose gene pool differs from the source population |  | 2 |
| 13598535169 | bottleneck effect | when there is a severe drop in population size, certain alleles may be overrepresented among the survivors, others may be underrepresented, and some may be absent altogether |  | 3 |
| 13598535170 | directional selection | when conditions favor individuals exhibiting one extreme of a phenotypic range, thereby shifting the frequency curve for the phenotypic character in one direction or the other |  | 4 |
| 13598535171 | disruptive selection | when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes |  | 5 |
| 13598535172 | stabilizing selection | acts against both extreme phenotypes and favors intermediate variants |  | 6 |
| 13598535173 | sexual dimorphism | marked differences between the two sexes in secondary sexual characteristics, which are not directly associated with reproduction or survival (differences in size, color, ornamentation, and behavior) |  | 7 |
| 13598535174 | heterozygote advantage | when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous | 8 | |
| 13598535175 | microevolution | changes over time in allele frequencies in a population | 9 | |
| 13598535176 | macroevolution | the broad pattern of evolution over long time spans | 10 | |
| 13598535177 | species | a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring- but do not produce viable, fertile offspring with members of other such groups | 11 | |
| 13598535178 | reproductive isolation | the existance of biological barriers that impede members of two species from producing viable offspring | 12 | |
| 13598535179 | hybrids | offspring that result from interspecific mating |  | 13 |
| 13598535180 | prezygotic barriers | impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic) |  | 14 |
| 13598535181 | post zygotic barriers | prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown | 15 | |
| 13598535182 | allopatric speciation | Speciation occurs as a result of geographic isolation. |  | 16 |
| 13598535183 | sympatric speciation | speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection) |  | 17 |
| 13598535184 | endosymbiosis | mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells |  | 18 |
| 13598535185 | adaptive radiation | Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill vacant ecological roles in their communities |  | 19 |
| 13598535186 | phylogeny | the evolutionary history of a species or group of species |  | 20 |
| 13598535187 | phylogenetic tree | evolutionary history of a group of organisms represented in a branching diagram |  | 21 |
| 13598535188 | Abiogenesis | origin of life from nonliving matter | 22 | |
| 13598535189 | Artificial selection | The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits | 23 | |
| 13598535190 | Endosymbiosis | A process in which a unicellular organism engulfs another cell, which lives within the host cell and ultimately becomes an organelle in the host cell. Example: Mitochondria and chloroplasts were once independent cells. | 24 | |
| 13598535191 | Founder effect | Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population | 25 | |
| 13598535192 | Hardy-Weinberg principle | The principle that frequencies of alleles and genotypes in a population remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work | 26 | |
| 13598535193 | Heterozygous advantage | Greater reproductive success of heterozygous individuals compared with homozygotes and tends to preserve variation in a gene pool (example: carriers of the sickle cell allele, which are immune to malaria but are not homozygous and do not have the sickle cell disease). | 27 | |
| 13598535194 | Macroevolution | Evolution which results in speciation (formation of a new species). | 28 | |
| 13598535195 | Microevolution | Evolutionary change within a population. A change in the allele frequencies in a population over generations. | 29 | |
| 13598535196 | Phylogenic tree | A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms | 30 | |
| 13598535197 | Sympatric speciation | The formation of new species in populations that live in the same geographic area | 31 | |
| 13598535251 | evolutionary adaptation | An accumulation of inherited characteristics that enhance organisms' ability to survive and reproduce in specific environments. |  | 32 |
| 13598535252 | artificial selection | human modification of species for desired traits through selective breeding |  | 33 |
| 13598535253 | descent with modification | each living species has descended, with changes, from other species over time |  | 34 |
| 13598535254 | founder effect | When a small number of individuals colonize a new area; the new gene pool is not reflective of original population. |  | 35 |
| 13598535255 | fitness | ability of an organism to survive in its environment and pass on its genes |  | 36 |
| 13598535256 | homology | Similarity resulting from common ancestry. |  | 37 |
| 13598535257 | population genetics | Study of allele frequency distribution and change under the influence of evolutionary processes. |  | 38 |
| 13598535258 | Hardy-Weinberg Theorem | measures changes in allele frequencies over time; Provides an "ideal" population to use as a basis of comparison. |  | 39 |
| 13598535259 | sexual recombination | Crossing over and shuffling of genes during meiosis. |  | 40 |
| 13598535260 | quantitative characteristic | Characteristic that varies along a continuum, usually due to influence of two or more genes. |  | 41 |
| 13598535261 | geographic variation | Difference in variation between population subgroups in different areas. |  | 42 |
| 13598535262 | cline | A graded change in a trait along a geographic axis. |  | 43 |
| 13598535263 | relative fitness | Fitness of a particular genotype. |  | 44 |
| 13598535264 | directional selection | Shift in allele frequency toward a favorable variation. |  | 45 |
| 13598535265 | disruptive selection | Shift in allele frequency toward the extremes of a range of phenotypes |  | 46 |
| 13598535266 | stabilizing selection | Shift in allele frequency that favors the average trait |  | 47 |
| 13598535267 | heterozygous advantage | condition where heterozygotes are fittent; maintains recessive alleles in a population; ex: Sickle Cell Anemia |  | 48 |
| 13598535268 | sexual selection | certain traits increase mating success |  | 49 |
| 13598535269 | sexual dimorphism | Differences between the sexes in secondary sexual characteristics. |  | 50 |
| 13598535270 | biological species concept | A species is a group of populations whose members have the potential to produce fertile offspring. |  | 51 |
| 13598535271 | reproductive isolation | Barriers that impede members of two different species from producing fertile offspring. |  | 52 |
| 13598535272 | prezygotic barriers | Barriers that impede mating or hinder fertilization. |  | 53 |
| 13598535273 | habitat isolation | two species do not interbreed because they encounter each other only rarely. |  | 54 |
| 13598535274 | temporal isolation | two species do not interbreed because they breed at different times of day, season, or years. |  | 55 |
| 13598535275 | behavioral isolation | two species do not interbreed because they have incompatible courtship rituals, pheromones, or bird songs. |  | 56 |
| 13598535276 | mechanical isolation | two species do not interbreed because morphological differences prevent fertilization. |  | 57 |
| 13598535277 | gametic isolation | two species do not interbreed because sperm can't fertilize the eggs. |  | 58 |
| 13598535278 | postzygotic barriers | Barriers that prevent the hybrid zygote from becoming a fertile adult. |  | 59 |
| 13598535279 | reduced hybrid viability | genes of different species interact and impair hybrid development. |  | 60 |
| 13598535280 | reduced hybrid fertility | Sterile hybrids, often due to uneven chromosome number. |  | 61 |
| 13598535281 | hybrid breakdown | Hybrid is fertile, but when they breed the next generation is sterile. |  | 62 |
| 13598535282 | allopatric speciation | When a population is divided; leads to speciation. | | 63 |
| 13598535283 | sympatric speciation | Speciation without a divided population. | | 64 |
| 13598535284 | polyploidy | In plants, the result of an extra set of chromosomes during cell division. |  | 65 |
| 13598535285 | adaptive radiation | Evolution of many new species from a common ancestor as a result of introduction to new environments. | 66 | |
| 13598535286 | systematics | Analytical approach to understanding the diversity and relationships of present and past organisms. |  | 67 |
| 13598535287 | analogy | Anatomical similarity due to convergent evolution; creates analogous structures |  | 68 |
| 13598535288 | clade | A taxonomic grouping that includes only a single ancestor and all of its descendants. |  | 69 |
| 13598535289 | cladistics | A phylogenetic classification system that uses shared derived characters and ancestry as the sole criterion for grouping taxa. |  | 70 |
| 13598535290 | monophyletic group | A taxonomic grouping that includes an ancestral species and all of its descendants. |  | 71 |
| 13598535291 | paraphyletic group | A monophyletic group in which some descendants of the common ancestor have been removed. |  | 72 |
| 13598535292 | polyphyletic group | A taxonomic grouping consisting of several species that lack a common ancestor (more work is needed to uncover species that tie them together into a monophyletic clade). |  | 73 |
| 13598535293 | shared primitive character | Trait shared beyond the taxon. |  | 74 |
| 13598535294 | shared derived character | Evolutionary novelty unique to that clade. |  | 75 |
| 13598535295 | outgroups | Species or group of species closely related to the ingroup. |  | 76 |
| 13598535296 | Miller-Urey Experiment | Experiment that found that organic molecules can form in a strongly reducing atmosphere. |  | 77 |
| 13598535297 | radiometric dating | Dating using decay of radioactive isotopes. |  | 78 |
| 13598535298 | radioisotopes | Isotopes that have unstable nuclei and undergo radioactive decay. |  | 79 |
| 13598535299 | endosymbiotic theory | Ancestors of mitochondria and plastids were prokaryotes that came to live in a host cell. |  | 80 |
| 13598535300 | colony | Collection of autonomously replicating cells. |  | 81 |
| 13598535301 | antibiotic resistance | Resistance evolving rapidly in many species of prokaryotes due to overuse of antibiotics, especially in agriculture. |  | 82 |
| 13598535198 | homologous structures | structures in different species that are similar because of common ancestry |  | 83 |
| 13598535199 | vestigial structures | remnants of features that served important functions in the the organism's ancestors |  | 84 |
| 13598535200 | convergent evolution | the independent evolution of similar features in different lineages | | 85 |
| 13598535201 | Hardy-Weinberg | the frequencies of alleles and genotypes in a population will remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work |  | 86 |
| 13598535202 | gene pool | the aggregate of all of the alleles for all of the loci in individuals in a population |  | 87 |
| 13598535203 | population | a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring | | 88 |
| 13598535204 | natural selection | a process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics |  | 89 |
| 13598535205 | genetic drift | changes in the gene pool due to random events | 90 | |
| 13598535206 | founder effect | when a individuals become isolated from a larger population, this smaller group may establish a new population whose gene pool differs from the source population | | 91 |
| 13598535207 | bottleneck effect | when there is a severe drop in population size, certain alleles may be overrepresented among the survivors, others may be underrepresented, and some may be absent altogether | | 92 |
| 13598535208 | gene flow | the transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes | 93 | |
| 13598535209 | directional selection | when conditions favor individuals exhibiting one extreme of a phenotypic range, thereby shifting the frequency curve for the phenotypic character in one direction or the other | | 94 |
| 13598535210 | disruptive selection | when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes | | 95 |
| 13598535211 | stabilizing selection | acts against both extreme phenotypes and favors intermediate variants | | 96 |
| 13598535212 | sexual selection | a form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates |  | 97 |
| 13598535213 | sexual dimorphism | marked differences between the two sexes in secondary sexual characteristics, which are not directly associated with reproduction or survival (differences in size, color, ornamentation, and behavior) | | 98 |
| 13598535214 | diploidy | the state of being diploid, that is having two sets of chromosomes | 99 | |
| 13598535215 | heterozygote advantage | when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous | 100 | |
| 13598535216 | frequency-dependent selection | fitness of a phenotype declines if it becomes too common in the population | 101 | |
| 13598535217 | speciation | the process by which one species splits into two or more species |  | 102 |
| 13598535218 | microevolution | changes over time in allele frequencies in a population | 103 | |
| 13598535219 | hybrids | offspring that result from interspecific mating | | 104 |
| 13598535220 | prezygotic barriers | impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic) | | 105 |
| 13598535221 | post zygotic barriers | prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown | 106 | |
| 13598535222 | allopatric speciation | gene flow is interrupted when a population is divided into geographically isolated subpopulations | | 107 |
| 13598535223 | sympatric speciation | speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection) | | 108 |
| 13598535224 | polyploidy | extra sets of chromosomes due to accidents during cell division | | 109 |
| 13598535225 | punctuated equilibrium | the theory that in the evolution there are long periods of little morphological change punctuated by relatively short periods of significant change |  | 110 |
| 13598535226 | endosymbiosis | mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells | | 111 |
| 13598535227 | adaptive radiation | Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill vacant ecological roles in their communities | | 112 |
| 13598535228 | homeotic genes | master regulatory genes that determine such basic features as where a pair of wings and a pair of legs will develop on a bird or how a plant's flower parts are arranged | 113 | |
| 13598535229 | phylogeny | the evolutionary history of a species or group of species | | 114 |
| 13598535230 | phylogenetic tree | evolutionary history of a group of organisms represented in a branching diagram | | 115 |
| 13598535231 | analogy | similarity due to convergent evolution | | 116 |
| 13598535232 | homology | similarity due to shared ancestry | | 117 |
| 13598535233 | clade | a group of species which includes an ancestral species and all of its descendants | 118 | |
| 13598535234 | outgroup | a species or group of species from an evolutionary lineage that is known to have diverged before the lineage that includes the species we are studying | 119 | |
| 13598535235 | Darwin's Theory (five parts) | 1. Variation 2. Overproduction 3. Competition 4. Survival of the fittest 5. Overtime, emergence of new species (new alleles) | 120 | |
| 13598535236 | Abiogenesis | origin of life from nonliving matter | 121 | |
| 13598535237 | abiotic synthesis | formation of organic molecules from inorganic material | 122 | |
| 13598535238 | extinction | total disappearance of all members of a species | 123 | |
| 13598535239 | mass extinction | total disappearance of a large number a species within a few million years | 124 | |
| 13598535240 | extant | still in existance | 125 | |
| 13598535241 | fitness | ability to produce surviving offspring | 126 | |
| 13598535242 | morphological species concept | new species differ by physical characteristics known as diagnostic traits | 127 | |
| 13598535243 | evolutionary species concept | members of a species share distinct evolutionary pathway and common traits | 128 | |
| 13598535244 | phylogenetic species concept | a family tree is used to identify species based on a common ancestor | 129 | |
| 13598535245 | biological species concept | species are identified as separate because of reproductive isolation. | 130 | |
| 13598535246 | plate tectonics | branch of geology which follows the movement of pieces of Earth's crust which float on a lower, hot mantle layer | 131 | |
| 13598535247 | continental drift | change over time of the positions of the continents | 132 | |
| 13598535248 | fossil | remains and traces of evidence of past life | 133 | |
| 13598535249 | paleontology | study of the fossil record | 134 | |
| 13598535250 | absolute dating | relies on radiometric dating to assign an age to a fossil | 135 |
