BLG 144 UPDATED ALL FINAL EXAMS QUESTIONS
AND ANSWERS SURE A+
✔✔frequent-dependent selection - ✔✔certain alleles are favoured when rare, not when
common
✔✔sampling error - ✔✔allele frequencies change due to blind luck
✔✔founder event - ✔✔when a group of individuals immigrate to a new geographic area
and establish a new population
✔✔founder effect - ✔✔change in allele frequencies due to new population
establishment
✔✔genetic bottleneck - ✔✔sudden reduction in the number of alleles in a population
✔✔gene flow - ✔✔movement of alleles from one population to another
-increases similiarity of allele frequencies in both populations as they become more
alike
-random in respect to fitness
✔✔mutation - ✔✔evolutionary mechanism that increases genetic diversity by changes
in makeup of chromosomes
, -slow compared to other mechanisms (gene flow)
✔✔deleterious alleles - ✔✔lower fitness
✔✔beneficial allele - ✔✔allows individuals to produce more offspring
✔✔inbreeding - ✔✔mating between relatives (share a common ancestor)
-makes hertozygotes into homozygotes
- does not cause evolution since there are no allele frequency changes (only changes
genotype frequencies)
-CAN SPEED THE RATE OF EVOLUTIONARY CHANGE by elimination deleterious
alleles - purifying selection
✔✔assortative mating - ✔✔when mating is nonrandom with respect to specific traits
✔✔difference between negative and positive assortment - ✔✔negative-individuals tend
to choose mates that differ in phenotypic traits
positibe- they tend to choose mates that are similar in phenotypic traits
✔✔sexual selection - ✔✔when individuals within a population differ in their ability to
attract mates
-favours individuals with heritable traits that enhance their ability to obtain mates
-violates hardy-weinberg
✔✔bateman- trivers theory - ✔✔-sexual selection usually acts more strongly on males
than on females, thus traits that attract members of the opposite sex are much more
highly elaborated in males
-"eggs are expensive but sperm are cheap" ---energetic cost
✔✔asymmetry of sex - ✔✔-females are choosy since they invest much more in their
offspring than males and will therefore need resources covered
✔✔how do females choose mates - ✔✔based on
1. physical characteristics that signal genetic quality
2. resources or parental care provided by males
3. orboth
✔✔why does sexual selection become more intense - ✔✔-there's male-male
competition for mates
-males tend to have many more traits that function only in courtship
✔✔sexual dimorphism - ✔✔refers to the any trait that differs between males and
females
AND ANSWERS SURE A+
✔✔frequent-dependent selection - ✔✔certain alleles are favoured when rare, not when
common
✔✔sampling error - ✔✔allele frequencies change due to blind luck
✔✔founder event - ✔✔when a group of individuals immigrate to a new geographic area
and establish a new population
✔✔founder effect - ✔✔change in allele frequencies due to new population
establishment
✔✔genetic bottleneck - ✔✔sudden reduction in the number of alleles in a population
✔✔gene flow - ✔✔movement of alleles from one population to another
-increases similiarity of allele frequencies in both populations as they become more
alike
-random in respect to fitness
✔✔mutation - ✔✔evolutionary mechanism that increases genetic diversity by changes
in makeup of chromosomes
, -slow compared to other mechanisms (gene flow)
✔✔deleterious alleles - ✔✔lower fitness
✔✔beneficial allele - ✔✔allows individuals to produce more offspring
✔✔inbreeding - ✔✔mating between relatives (share a common ancestor)
-makes hertozygotes into homozygotes
- does not cause evolution since there are no allele frequency changes (only changes
genotype frequencies)
-CAN SPEED THE RATE OF EVOLUTIONARY CHANGE by elimination deleterious
alleles - purifying selection
✔✔assortative mating - ✔✔when mating is nonrandom with respect to specific traits
✔✔difference between negative and positive assortment - ✔✔negative-individuals tend
to choose mates that differ in phenotypic traits
positibe- they tend to choose mates that are similar in phenotypic traits
✔✔sexual selection - ✔✔when individuals within a population differ in their ability to
attract mates
-favours individuals with heritable traits that enhance their ability to obtain mates
-violates hardy-weinberg
✔✔bateman- trivers theory - ✔✔-sexual selection usually acts more strongly on males
than on females, thus traits that attract members of the opposite sex are much more
highly elaborated in males
-"eggs are expensive but sperm are cheap" ---energetic cost
✔✔asymmetry of sex - ✔✔-females are choosy since they invest much more in their
offspring than males and will therefore need resources covered
✔✔how do females choose mates - ✔✔based on
1. physical characteristics that signal genetic quality
2. resources or parental care provided by males
3. orboth
✔✔why does sexual selection become more intense - ✔✔-there's male-male
competition for mates
-males tend to have many more traits that function only in courtship
✔✔sexual dimorphism - ✔✔refers to the any trait that differs between males and
females
