All flashcards
Flashcard 1: If p=0.60 and q=0.40, what are expected genotype frequencies AA,Aa,aa?
Answer: AA=0.36, Aa=0.48, aa=0.16. Use p2, 2pq, and q2 formulas.
Flashcard 2: What is the term for similarity in traits due to similar function, not shared ancestry?
Answer: Analogy. Similar function evolved independently, not inheritance.
Flashcard 3: If two populations become more genetically similar after migration between them, which mechanism fits?
Answer: Gene flow. Migration makes populations more genetically similar.
Flashcard 4: If a trait mean steadily increases across time points, which selection pattern is most consistent?
Answer: Directional selection. Consistent shift in one direction indicates selection.
Flashcard 5: If trait variance decreases while the mean stays similar over time, which selection is most consistent?
Answer: Stabilizing selection. Reduced variance with stable mean indicates stabilizing.
Flashcard 6: If intermediate phenotypes decline and both extremes increase over generations, which selection fits?
Answer: Disruptive selection. Extremes increase while intermediates decrease.
Flashcard 7: If allele frequencies change rapidly after a storm drastically reduces population size, what cause fits?
Answer: Bottleneck effect (genetic drift). Sudden population reduction causes random changes.
Flashcard 8: If a new population has allele frequencies very different from the source population at founding, what cause fits?
Answer: Founder effect (genetic drift). Small founding group creates different frequencies.
Flashcard 9: If two populations become more genetically similar after migration between them, which mechanism fits?
Answer: Gene flow. Migration makes populations more genetically similar.
Flashcard 10: If a harmful recessive allele persists because heterozygotes have highest fitness, what mechanism is shown?
Answer: Heterozygote advantage (balancing selection). Mixed genotype has highest fitness, maintaining both alleles.
Flashcard 11: If allele frequencies cycle because rare phenotypes have higher fitness, what mechanism is indicated?
Answer: Negative frequency-dependent selection. Rare types have advantage, preventing fixation.
Flashcard 12: Which option best interprets a consistent increase in antibiotic-resistant bacteria after treatment?
Answer: Natural selection increased resistance allele frequency. Antibiotic creates selective pressure favoring resistance.
Flashcard 13: Which option best interprets a rapid rise of pesticide resistance after pesticide use begins?
Answer: Directional selection favoring resistant individuals. Pesticide selects for resistant individuals over time.
Flashcard 14: What is the term for random change in allele frequencies that is strongest in small populations?
Answer: Genetic drift. Random sampling effects vary inversely with population size.
Flashcard 15: If genotype frequencies match p2:2pq:q2 and remain constant, what is the conclusion?
Answer: Population is in Hardy–Weinberg equilibrium at that locus. Genotype frequencies match predictions and stay constant.
Flashcard 16: If allele frequency changes from p=0.40 to p=0.55 across generations, what occurred?
Answer: Evolution occurred (allele frequencies changed). Allele frequency change indicates evolutionary change.
Flashcard 17: What relationship must allele frequencies satisfy at a two-allele locus when computed from data?
Answer: p+q=1. Two allele frequencies must sum to one.
Flashcard 18: If allele frequency changes are larger in a small population than a large one, what trend does this show?
Answer: Stronger genetic drift in smaller populations. Smaller populations show larger random fluctuations.
Flashcard 19: What is the term for a trait that is favored because it increases mating success in data trends?
Answer: Sexual selection. Traits evolve to increase reproductive opportunities.
Flashcard 20: If male ornament size increases while survival decreases but mating success increases, what selection fits?
Answer: Sexual selection. Ornaments increase mating despite survival costs.
Flashcard 21: What is the term for a split in one lineage into two or more lineages shown in phylogenetic data?
Answer: Speciation. One lineage splits into multiple separate lineages.
Flashcard 22: What is the term for speciation caused by geographic isolation, often inferred from range data?
Answer: Allopatric speciation. Geographic barriers separate populations, preventing gene flow.
Flashcard 23: Which equation gives allele frequency q for allele a from genotype counts AA,Aa,aa?
Answer: q=2N2aa+Aa. Counts both homozygotes and half the heterozygotes.
Flashcard 24: Which equation gives allele frequency p for allele A from genotype counts AA,Aa,aa?
Answer: p=2N2AA+Aa. Counts both homozygotes and half the heterozygotes.
Flashcard 25: What is the term for speciation without geographic separation, inferred from within-range divergence?
Answer: Sympatric speciation. Populations diverge in the same geographic area.
Flashcard 26: What is the term for a DNA sequence difference used to track evolutionary change in populations?
Answer: Genetic marker. DNA variations help track population changes.
Flashcard 27: Which option best defines reproductive isolation when interpreting speciation evidence?
Answer: Barriers prevent gene flow between populations. Populations cannot successfully interbreed and exchange genes.
Flashcard 28: If two populations show increasing genetic divergence and decreasing hybrid fertility, what conclusion fits?
Answer: Reproductive isolation is increasing toward speciation. Genetic differences and breeding barriers are developing.
Flashcard 29: What is the term for a gradual change within a lineage over time as seen in fossil sequences?
Answer: Anagenesis. Single lineage changes gradually over time.
Flashcard 30: What is the term for long periods of little change punctuated by rapid change in the fossil record?
Answer: Punctuated equilibrium. Rapid change alternates with periods of stasis.